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资助项目
0.05) between wild (AR = 4.651), semi-cultivated (AR = 5.091) and cultivated (AR = 5.132) populations of C. taliensis, which suggested that the genetic background of long-lived woody plant was not easy to be changed, and there were moderate high gene flow between populations. However, there was a significant difference (P < 0.05) between wild (AR = 5.9) and cultivated (AR = 7.1) populations distributed in the same place in Yun county, Yunnan province, which may result from the hybridization and introgression of species in the tea garden and anthropogenic damages to the wild population. The hypothesis of hybrid origin of C. grandibracteata was tested by morphological and microsatellites analyses. Compared with other species, the locules in ovary of C. grandibracteata are variable, which showed a morphological intermediate and mosaic. Except one private allele, Ninety-nine percent alleles of C. grandibracteata were shared with these of C. taliensis and C. sinensis var. assamica. And C. grandibracteata was nested in the cluster of C. taliensis in the UPGMA tree. Conclusively, our results supported the hypothesis of hybrid origin of C. grandibracteata partly. The speciation of C. grandibracteata was derived from hybridization and asymmetrical introgression potentially. It is possible that C. taliensis was one of its parents, but it still needs more evidences to prove that C. sinensis var. assamica was another 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Mai University","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Mutation&&fq=dc.project.title_filter%3AChiang%5C+Mai%5C+University"},{"jsname":"China Scholarship Council[201504910423]","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Mutation&&fq=dc.project.title_filter%3AChina%5C+Scholarship%5C+Council%5C%5B201504910423%5C%5D"},{"jsname":"Chinese Academy of Sciences[2013T2S0030]","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Mutation&&fq=dc.project.title_filter%3AChinese%5C+Academy%5C+of%5C+Sciences%5C%5B2013T2S0030%5C%5D"},{"jsname":"Chinese Academy of Sciences[2013T2S003]","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Mutation&&fq=dc.project.title_filter%3AChinese%5C+Academy%5C+of%5C+Sciences%5C%5B2013T2S003%5C%5D"},{"jsname":"Craigia yunnanensis W. W. Smith & W. E. Evans (Tiliaceae) is an endangered deciduous tree species which has high scientific and economic value. C. yunnanensis is seriously threatened and has been pushed to the verge of extinction due to vegetation destruction in China and consequent contraction of its distribution. Hence, it was listed as a nationally rare and endangered plant in 1999 and has also been proposed as a second-ranked plant for national protection in China and included in IUCN red list. As a scientifically important and valued tree species with endangered status, the wild populations of C. yunnanensis therefore represent is a genetic resource that must be conserved. To provide basic information for its conservation, the population dynamics and population size structures, pollination biology and breeding system, eleven fitness-related characters and the genetic variability based on AFLP were comprehensively studied. The main results are summarized as follows: A total of six wild populations of C. yunnanensis were found in two disjunct regions of Yunnan, i.e. WenShan (SE Yunnan) and DeHong (SW Yunnan), from 2005 to 2007. Additionally, in all but one of the populations we detected, mature trees were felled between 2005 and 2007, so destruction of most of these populations is ongoing. Across the six populations of extant C. yunnanensis found during our study, the total number of mature (reproductive) individuals detected was 584 in 2007，plus larger numbers of seedling and resprouts from cut trunks. The result of surveying Population structure showed that there are two regeneration types which are seedlings and sprouts. Seedlings occurred abundantly in gaps or open areas and the size class frequency distributions were often discontinuous, and the same general pattern occurred in all the investigated populations for juveniles and adults. The numbers of seed-origin individuals did however decline sharply with increasing size, indicating a high mortality rate going from seedling to sapling stage may be a problem for this species. Additionally, the cash crop cultivation and logging seriously threaten the survival of the species. We conducted field observations and artificial pollination experiments on the floral biology, pollination process and breeding system of Craigia yunnanensis in Fadou, Xichou county of Yunnan province. The lifespan of a single hermaphrodite flower is approximately 3-4 days. A cyme has 2-9 flowered. The flowering period of an inflorescence is usually 5-14 days. The flowers of C. yunnanensis were protandrous. The stamens were within petal-like staminodes in the opening flowers until the flower withered. Without touchment, the bractlike staminodes can’t open. Self-pollination was partially avoided by temporal and spatial isolation of male and female organs within the same flower. However, autogamous and geitonogamous pollination is unavoidable because of the large number of flowers on a single tree and the action of pollinators. The values of both OCI (≥4) and P/O (1381) and the results of bagging tests indicated there was no apomixes in C. yunnanensis and the breeding system of the species was outcrossing with partial self-compatibility and the pollinators were required during the pollination process. The most frequent effective floral visitor was only beautiful fly (Chrysomyia megacephala). Fruit set and seed set in natural condition were 56.67±3.85％ and 6.26±0.75％, respectively. Therefore, lack of pollinators, low pollination efficiency, unavoidable geitonogamous pollination and partial self-compatibility and inbreeding in small populations may account for the low fruit set, especially seed set.Variations in seed traits, seed germination, and seedling growth characters among six Craigia yunnanensis populations were evaluated. All seed and seedling traits exhibited significant differences among populations (P < 0.05). The fitness of seed as assessed by seed size, seed germination and seedling trait was independent of population size, except for the number of seeds per capsule (r = 0.93，P < 0.01). Correlations between geo-climatic variables of seed origin and seed and seedling related characters were insignificant (P > 0.05). For some populations, germination capacity in 12-h photoperiod was significantly higher than that in completed darkness（W-FD: P < 0.01, W-JD: P < 0.05）.Genetic variation within and among six populations was assessed using AFLP markers. Genetic diversity was higher at species level (PPL = 69.19%, HE = 0.221) than at population level (PPL = 26.22%, HE = 0.095, Is =0.140), and populations in southeast Yunnan were strongly differentiated from those in southwest Yunnan (Nei’s GST = 0.575; FST = 0.655). UPGMA analysis demonstrated a clear genetic division between the two populations from DeHong (SW Yunnan; D-JD and D-HG) and the four from WenShan (SE Yunnan; W-FD, W-LH, W-ML, and W-MG). Within-population genetic variation was significantly correlated with population isolation (r(PPL) = -0.94, P = 0.006; r(HE) = -0.85, P = 0.032; r(Is) = -0.87, P = 0.025), but not with population size (r(PPL) = 0.63, P = 0.178; r(HE) = 0.54, P = 0.268; r(Is) = 0.56, P = 0.249).","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Mutation&&fq=dc.project.title_filter%3ACraigia%5C+yunnanensis%5C+W.%5C+W.%5C+Smith%5C+%5C%26%5C+W.%5C+E.%5C+Evans%5C+%5C%28Tiliaceae%5C%29%5C+is%5C+an%5C+endangered%5C+deciduous%5C+tree%5C+species%5C+which%5C+has%5C+high%5C+scientific%5C+and%5C+economic%5C+value.%5C+C.%5C+yunnanensis%5C+is%5C+seriously%5C+threatened%5C+and%5C+has%5C+been%5C+pushed%5C+to%5C+the%5C+verge%5C+of%5C+extinction%5C+due%5C+to%5C+vegetation%5C+destruction%5C+in%5C+China%5C+and%5C+consequent%5C+contraction%5C+of%5C+its%5C+distribution.%5C+Hence%2C%5C+it%5C+was%5C+listed%5C+as%5C+a%5C+nationally%5C+rare%5C+and%5C+endangered%5C+plant%5C+in%5C+1999%5C+and%5C+has%5C+also%5C+been%5C+proposed%5C+as%5C+a%5C+second%5C-ranked%5C+plant%5C+for%5C+national%5C+protection%5C+in%5C+China%5C+and%5C+included%5C+in%5C+IUCN%5C+red%5C+list.%5C+As%5C+a%5C+scientifically%5C+important%5C+and%5C+valued%5C+tree%5C+species%5C+with%5C+endangered%5C+status%2C%5C+the%5C+wild%5C+populations%5C+of%5C+C.%5C+yunnanensis%5C+therefore%5C+represent%5C+is%5C+a%5C+genetic%5C+resource%5C+that%5C+must%5C+be%5C+conserved.%5C+To%5C+provide%5C+basic%5C+information%5C+for%5C+its%5C+conservation%2C%5C+the%5C+population%5C+dynamics%5C+and%5C+population%5C+size%5C+structures%2C%5C+pollination%5C+biology%5C+and%5C+breeding%5C+system%2C%5C+eleven%5C+fitness%5C-related%5C+characters%5C+and%5C+the%5C+genetic%5C+variability%5C+based%5C+on%5C+AFLP%5C+were%5C+comprehensively%5C+studied.%5C+The%5C+main%5C+results%5C+are%5C+summarized%5C+as%5C+follows%5C%3A%5C+A%5C+total%5C+of%5C+six%5C+wild%5C+populations%5C+of%5C+C.%5C+yunnanensis%5C+were%5C+found%5C+in%5C+two%5C+disjunct%5C+regions%5C+of%5C+Yunnan%2C%5C+i.e.%5C+WenShan%5C+%5C%28SE%5C+Yunnan%5C%29%5C+and%5C+DeHong%5C+%5C%28SW%5C+Yunnan%5C%29%2C%5C+from%5C+2005%5C+to%5C+2007.%5C+Additionally%2C%5C+in%5C+all%5C+but%5C+one%5C+of%5C+the%5C+populations%5C+we%5C+detected%2C%5C+mature%5C+trees%5C+were%5C+felled%5C+between%5C+2005%5C+and%5C+2007%2C%5C+so%5C+destruction%5C+of%5C+most%5C+of%5C+these%5C+populations%5C+is%5C+ongoing.%5C+Across%5C+the%5C+six%5C+populations%5C+of%5C+extant%5C+C.%5C+yunnanensis%5C+found%5C+during%5C+our%5C+study%2C%5C+the%5C+total%5C+number%5C+of%5C+mature%5C+%5C%28reproductive%5C%29%5C+individuals%5C+detected%5C+was%5C+584%5C+in%5C+2007%EF%BC%8Cplus%5C+larger%5C+numbers%5C+of%5C+seedling%5C+and%5C+resprouts%5C+from%5C+cut%5C+trunks.%5C+The%5C+result%5C+of%5C+surveying%5C+Population%5C+structure%5C+showed%5C+that%5C+there%5C+are%5C+two%5C+regeneration%5C+types%5C+which%5C+are%5C+seedlings%5C+and%5C+sprouts.%5C+Seedlings%5C+occurred%5C+abundantly%5C+in%5C+gaps%5C+or%5C+open%5C+areas%5C+and%5C+the%5C+size%5C+class%5C+frequency%5C+distributions%5C+were%5C+often%5C+discontinuous%2C%5C+and%5C+the%5C+same%5C+general%5C+pattern%5C+occurred%5C+in%5C+all%5C+the%5C+investigated%5C+populations%5C+for%5C+juveniles%5C+and%5C+adults.%5C+The%5C+numbers%5C+of%5C+seed%5C-origin%5C+individuals%5C+did%5C+however%5C+decline%5C+sharply%5C+with%5C+increasing%5C+size%2C%5C+indicating%5C+a%5C+high%5C+mortality%5C+rate%5C+going%5C+from%5C+seedling%5C+to%5C+sapling%5C+stage%5C+may%5C+be%5C+a%5C+problem%5C+for%5C+this%5C+species.%5C+Additionally%2C%5C+the%5C+cash%5C+crop%5C+cultivation%5C+and%5C+logging%5C+seriously%5C+threaten%5C+the%5C+survival%5C+of%5C+the%5C+species.%5C+We%5C+conducted%5C+field%5C+observations%5C+and%5C+artificial%5C+pollination%5C+experiments%5C+on%5C+the%5C+floral%5C+biology%2C%5C+pollination%5C+process%5C+and%5C+breeding%5C+system%5C+of%5C+Craigia%5C+yunnanensis%5C+in%5C+Fadou%2C%5C+Xichou%5C+county%5C+of%5C+Yunnan%5C+province.%5C+The%5C+lifespan%5C+of%5C+a%5C+single%5C+hermaphrodite%5C+flower%5C+is%5C+approximately%5C+3%5C-4%5C+days.%5C+A%5C+cyme%5C+has%5C+2%5C-9%5C+flowered.%5C+The%5C+flowering%5C+period%5C+of%5C+an%5C+inflorescence%5C+is%5C+usually%5C+5%5C-14%5C+days.%5C+The%5C+flowers%5C+of%5C+C.%5C+yunnanensis%5C+were%5C+protandrous.%5C+The%5C+stamens%5C+were%5C+within%5C+petal%5C-like%5C+staminodes%5C+in%5C+the%5C+opening%5C+flowers%5C+until%5C+the%5C+flower%5C+withered.%5C+Without%5C+touchment%2C%5C+the%5C+bractlike%5C+staminodes%5C+can%E2%80%99t%5C+open.%5C+Self%5C-pollination%5C+was%5C+partially%5C+avoided%5C+by%5C+temporal%5C+and%5C+spatial%5C+isolation%5C+of%5C+male%5C+and%5C+female%5C+organs%5C+within%5C+the%5C+same%5C+flower.%5C+However%2C%5C+autogamous%5C+and%5C+geitonogamous%5C+pollination%5C+is%5C+unavoidable%5C+because%5C+of%5C+the%5C+large%5C+number%5C+of%5C+flowers%5C+on%5C+a%5C+single%5C+tree%5C+and%5C+the%5C+action%5C+of%5C+pollinators.%5C+The%5C+values%5C+of%5C+both%5C+OCI%5C+%5C%28%E2%89%A54%5C%29%5C+and%5C+P%5C%2FO%5C+%5C%281381%5C%29%5C+and%5C+the%5C+results%5C+of%5C+bagging%5C+tests%5C+indicated%5C+there%5C+was%5C+no%5C+apomixes%5C+in%5C+C.%5C+yunnanensis%5C+and%5C+the%5C+breeding%5C+system%5C+of%5C+the%5C+species%5C+was%5C+outcrossing%5C+with%5C+partial%5C+self%5C-compatibility%5C+and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species, usually called tree ferns, are considered as relicts of a time when dinosaurs were common. In recent several decades, the number of Cyatheaceae plants decreases dramatically. In order to find the reasons and provide directions for protecting these endangered plants, the biological characteristics of Cyatheaceae were surveyed. Using AFLP and cpDNA sequence variations, the genetic diversity and phylogeography of Sphaeropteris brunoniana were also analyzed. Based on these findings, implications for conservation strategies were discussed for this relict tree fern. Main results of the dissertation were summarized as follows, (1) Cyatheaceae plants have extensive distribution in Yunnan, China, and most of them distribute in southeast of Yunnan. In southeast, they usually inhabit margins of evergreen broad-leaved forests or secondary coniferous forests; however, the population update is very different and the age structure is unscientific. The spore of Cyatheaceae is trilete, radially symmetrical, and perinous. The spores of Alsophila species feature a ridged perine and a granular, verrucate or smooth exine. The spores of S. brunoniana are characterized by an incipient granular outermost layer and a verrucate exine. The metaphase chromosome numbers of gametophytes in the three examined species, viz. A. podophylla, A. gigantea and A. austro-yunnanensis, are 69, indicating that they are diploid and do not display variety in chromosome number. The chemical constituents of S. brunoniana are main simple and familiar compounds, such as saccharides, fatty acids and alcohols, and stigmasterols. (2) An unexpectedly high level of nDNA genetic diversity and low cpDNA diversity were detected in S. brunoniana. (3) This study showed that the genetic differentiation among populations within regions was low and between regions was significant. (4) There were several refugia of S. brunoniana in Yunnan during glacial periods. The Hainan populations were likely new colonizations and originated from Southeast Asia. (5) To retain existing genetic diversity, whether in situ or ex situ conservation or collection of germplasm is used, the populations of the two regions should be considered equally. Furthermore, ex situ conservation of this species should be preferably conducted on large populations.","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Mutation&&fq=dc.project.title_filter%3ACyatheaceae%5C+species%2C%5C+usually%5C+called%5C+tree%5C+ferns%2C%5C+are%5C+considered%5C+as%5C+relicts%5C+of%5C+a%5C+time%5C+when%5C+dinosaurs%5C+were%5C+common.%5C+In%5C+recent%5C+several%5C+decades%2C%5C+the%5C+number%5C+of%5C+Cyatheaceae%5C+plants%5C+decreases%5C+dramatically.%5C+In%5C+order%5C+to%5C+find%5C+the%5C+reasons%5C+and%5C+provide%5C+directions%5C+for%5C+protecting%5C+these%5C+endangered%5C+plants%2C%5C+the%5C+biological%5C+characteristics%5C+of%5C+Cyatheaceae%5C+were%5C+surveyed.%5C+Using%5C+AFLP%5C+and%5C+cpDNA%5C+sequence%5C+variations%2C%5C+the%5C+genetic%5C+diversity%5C+and%5C+phylogeography%5C+of%5C+Sphaeropteris%5C+brunoniana%5C+were%5C+also%5C+analyzed.%5C+Based%5C+on%5C+these%5C+findings%2C%5C+implications%5C+for%5C+conservation%5C+strategies%5C+were%5C+discussed%5C+for%5C+this%5C+relict%5C+tree%5C+fern.%5C+Main%5C+results%5C+of%5C+the%5C+dissertation%5C+were%5C+summarized%5C+as%5C+follows%2C%5C+%5C%281%5C%29%5C+Cyatheaceae%5C+plants%5C+have%5C+extensive%5C+distribution%5C+in%5C+Yunnan%2C%5C+China%2C%5C+and%5C+most%5C+of%5C+them%5C+distribute%5C+in%5C+southeast%5C+of%5C+Yunnan.%5C+In%5C+southeast%2C%5C+they%5C+usually%5C+inhabit%5C+margins%5C+of%5C+evergreen%5C+broad%5C-leaved%5C+forests%5C+or%5C+secondary%5C+coniferous%5C+forests%5C%3B%5C+however%2C%5C+the%5C+population%5C+update%5C+is%5C+very%5C+different%5C+and%5C+the%5C+age%5C+structure%5C+is%5C+unscientific.%5C+The%5C+spore%5C+of%5C+Cyatheaceae%5C+is%5C+trilete%2C%5C+radially%5C+symmetrical%2C%5C+and%5C+perinous.%5C+The%5C+spores%5C+of%5C+Alsophila%5C+species%5C+feature%5C+a%5C+ridged%5C+perine%5C+and%5C+a%5C+granular%2C%5C+verrucate%5C+or%5C+smooth%5C+exine.%5C+The%5C+spores%5C+of%5C+S.%5C+brunoniana%5C+are%5C+characterized%5C+by%5C+an%5C+incipient%5C+granular%5C+outermost%5C+layer%5C+and%5C+a%5C+verrucate%5C+exine.%5C+The%5C+metaphase%5C+chromosome%5C+numbers%5C+of%5C+gametophytes%5C+in%5C+the%5C+three%5C+examined%5C+species%2C%5C+viz.%5C+A.%5C+podophylla%2C%5C+A.%5C+gigantea%5C+and%5C+A.%5C+austro%5C-yunnanensis%2C%5C+are%5C+69%2C%5C+indicating%5C+that%5C+they%5C+are%5C+diploid%5C+and%5C+do%5C+not%5C+display%5C+variety%5C+in%5C+chromosome%5C+number.%5C+The%5C+chemical%5C+constituents%5C+of%5C+S.%5C+brunoniana%5C+are%5C+main%5C+simple%5C+and%5C+familiar%5C+compounds%2C%5C+such%5C+as%5C+saccharides%2C%5C+fatty%5C+acids%5C+and%5C+alcohols%2C%5C+and%5C+stigmasterols.%5C+%5C%282%5C%29%5C+An%5C+unexpectedly%5C+high%5C+level%5C+of%5C+nDNA%5C+genetic%5C+diversity%5C+and%5C+low%5C+cpDNA%5C+diversity%5C+were%5C+detected%5C+in%5C+S.%5C+brunoniana.%5C+%5C%283%5C%29%5C+This%5C+study%5C+showed%5C+that%5C+the%5C+genetic%5C+differentiation%5C+among%5C+populations%5C+within%5C+regions%5C+was%5C+low%5C+and%5C+between%5C+regions%5C+was%5C+significant.%5C+%5C%284%5C%29%5C+There%5C+were%5C+several%5C+refugia%5C+of%5C+S.%5C+brunoniana%5C+in%5C+Yunnan%5C+during%5C+glacial%5C+periods.%5C+The%5C+Hainan%5C+populations%5C+were%5C+likely%5C+new%5C+colonizations%5C+and%5C+originated%5C+from%5C+Southeast%5C+Asia.%5C+%5C%285%5C%29%5C+To%5C+retain%5C+existing%5C+genetic%5C+diversity%2C%5C+whether%5C+in%5C+situ%5C+or%5C+ex%5C+situ%5C+conservation%5C+or%5C+collection%5C+of%5C+germplasm%5C+is%5C+used%2C%5C+the%5C+populations%5C+of%5C+the%5C+two%5C+regions%5C+should%5C+be%5C+considered%5C+equally.%5C+Furthermore%2C%5C+ex%5C+situ%5C+conservation%5C+of%5C+this%5C+species%5C+should%5C+be%5C+preferably%5C+conducted%5C+on%5C+large%5C+populations."},{"jsname":"Cycas micholitzii complex is composed of 5 species: C. micholitzii Dyer, C. bifida (Dyer) K. D. Hill,C. longipetiolula D. Y. Wang, C. debaoensis Y. C. Zhong et C J. Chen, C. multipinnata C J. Chen et S. Y. Yang，and distributed from southwest China to central Vietnam and eastern Laos. Based on sequence data from two maternally inherited cpDNA and one biparentally nuclear DNA fragments, our study revealed the population genetic structure of C. micholitzii complex and explored the potential causes. The evolutionary and demographic histories were investigated. The genetic relationship among species in the complex was also clarified.The results were summarized as follows: 1. Phylogeographic analysis based on chloroplast sequences，We examined chloroplast sequence variation of the atpB-rbcLand psbA-trnHintergenic spacers in 27 populations of C. micholitzii complex, recovering 26 haplotypes. The average within-population diversity (HS = 0.140) was low while total diversity (HT = 0.911) was high. Population differentiation was also high(GST = 0.846, NST = 0.919), indicating significant phylogeographical structure (NST > GST,p < 0.001) and low levels of seed-based gene flow. C. debaoensis (Cycadaceae) is an endangered species restricted to the border of Guangxi and Yunnan province in southwest China. This species has been classified into two types: sand and karst, according to the soil matrix they grow on. We examined chloroplast sequence variation of the cpDNA sequences from 11 populations of this species. Significant population genetic differentiation was detected (GST= 0.684 and FST = 0.74160). There was marked genetic differentiation between populations in the sand and karst regions and no expansion was detected. Climate changes during glacial periods have had significant effects on the current distribution of cycads. The molecular phylogenetic data, together with the geographic distribution of the haplotypes, suggest that C. debaoensis experienced range contraction during glacial periods, and that the current populations are still confined to the original refugia in southwest China which have favorable habitats in glacial period. These results imply that small refugia were maintained in both sand and karst regions during the LGM (last glacial maximum). This species had no postglacial recolonization and only stayed in these refugia up to now. The low within-population diversity of C. debaoensis suggests that there were strong bottleneck events or founder effects within each separate region during the Quaternary climatic oscillations. Relatively high genetic and haplotype diversities were detected in the newly discovered populations, which located at intermediate locality of sand regions and had morphological variation; this is probably the consequence of the admixture of different haplotypes colonizing the area from separate sources. C. micholitzii occurs in the Annan Highlands in central Vietnam near the Laos border. C. bifida occurs in North Vietnam; its distribution extends across the border into adjacent localities in Guangxi and Yunnan in China. For the comparability between them,theywere considered as the same species C. micholitzii by many academicians. The cpDNA sequences from 11 populations showed that these very controversial species, C. micholitzii and C. bifida, is paraphyletic and should belong to the same species C. micholitzii. AMOVA analysis showed that the component of among-population within region/species (76.46%) was unexpectedly larger than the among-species/region component (14.97%), which also indicates that there is no justification for recognizing two species as C. micholitzii and C. bifida. This hypothesis was also supported by the geological data, especially the neotectonic history of the indo-china block, which started to move south since Oligocene and cause the geographic isolation of these two groups. Therefore, the most likely explanation to the phenotypic similarities between these two groups may be the retention of ancestral polymorphisms in the paraphyletic group due to incomplete lineage sorting. Furthermore, the similarities may also be ascribed to pollen-mediated gene flow among geographically proximate populations and/or phenotypic convergence under similar selection schemes in the same region. C.micholitzi had the higest genetic diversity (HT = 0.980,) and genetic differentiation (GST = 0.830, NST = 0.915) among the C. micholitzii complex. The high genetic diversity might be attributed to its long evolutionary history, highly diverse habitats. The ineffective mode of seed dispersal and dramatic neotectonic movement in the distribution range of this species could result in the high genetic differentiation. 2. Phylogeographic analysis based on nuclear ribosomal sequences, We sequenced the nrDNA ITS in all 27 populations sampled, 7 haplotypes were identified, among which C. micholitzii had 6, while C. multipinnata, C. longipetiolula and C. debaoensis shared the remaining one. Compared to chloroplast genes, nuclear genes had higher correlation between genetic and geographical distance, but lower interspecies differentiation (54.42% vs 25.24%). Phylogeographical structure of C. micholitzii and C.bifida based on ITS Variation was consistent with the morphology differentiation. This similar in nuclear gene should be ascribed to pollen-mediated gene flow among geographically proximate populations.Long-distance gene flow over the two groups was clearly interrupted, which brought on the nrDNA genetic differenciation between the geographically isolated groups, to a certain extent affected the morphological variation. 3. Interspecies relationships among Cycas micholitzii complex, We analysed chloroplast sequence variation of the atpB-rbcL and psbA-trnH intergenic spacers in 27 populations sampled of C. micholitzii complex, AMOVA analysis showed that the component of among-species/region component (59.21%). However, phylogenic analysis showed that the haplotypes of C. micholitzii complex couldn`t grouped into four clusters closely corresponding to the narrowly defined C. micholitzi, C. multipinnata, C. debaoensis and C. longipetiolula. We concluded that the conflict may result from several factors: firstly incomplete lineage sorting of C. micholitzii; secondly hybridization/introgression of sympatrically cycads, which would be supported by evidence base on nrDNA ITS sequences; thirdly intramolecular recombination in cpDNA of cycads; eventually the neotectonic movement in the distribution range of this species.","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Mutation&&fq=dc.project.title_filter%3ACycas%5C+micholitzii%5C+complex%5C+is%5C+composed%5C+of%5C+5%5C+species%5C%3A%5C+C.%5C+micholitzii%5C+Dyer%2C%5C+C.%5C+bifida%5C+%5C%28Dyer%5C%29%5C+K.%5C+D.%5C+Hill%2CC.%5C+longipetiolula%5C+D.%5C+Y.%5C+Wang%2C%5C+C.%5C+debaoensis%5C+Y.%5C+C.%5C+Zhong%5C+et%5C+C%5C+J.%5C+Chen%2C%5C+C.%5C+multipinnata%5C+C%5C+J.%5C+Chen%5C+et%5C+S.%5C+Y.%5C+Yang%EF%BC%8Cand%5C+distributed%5C+from%5C+southwest%5C+China%5C+to%5C+central%5C+Vietnam%5C+and%5C+eastern%5C+Laos.%5C+Based%5C+on%5C+sequence%5C+data%5C+from%5C+two%5C+maternally%5C+inherited%5C+cpDNA%5C+and%5C+one%5C+biparentally%5C+nuclear%5C+DNA%5C+fragments%2C%5C+our%5C+study%5C+revealed%5C+the%5C+population%5C+genetic%5C+structure%5C+of%5C+C.%5C+micholitzii%5C+complex%5C+and%5C+explored%5C+the%5C+potential%5C+causes.%5C+The%5C+evolutionary%5C+and%5C+demographic%5C+histories%5C+were%5C+investigated.%5C+The%5C+genetic%5C+relationship%5C+among%5C+species%5C+in%5C+the%5C+complex%5C+was%5C+also%5C+clarified.The%5C+results%5C+were%5C+summarized%5C+as%5C+follows%5C%3A%5C+1.%5C+Phylogeographic%5C+analysis%5C+based%5C+on%5C+chloroplast%5C+sequences%EF%BC%8CWe%5C+examined%5C+chloroplast%5C+sequence%5C+variation%5C+of%5C+the%5C+atpB%5C-rbcLand%5C+psbA%5C-trnHintergenic%5C+spacers%5C+in%5C+27%5C+populations%5C+of%5C+C.%5C+micholitzii%5C+complex%2C%5C+recovering%5C+26%5C+haplotypes.%5C+The%5C+average%5C+within%5C-population%5C+diversity%5C+%5C%28HS%5C+%3D%5C+0.140%5C%29%5C+was%5C+low%5C+while%5C+total%5C+diversity%5C+%5C%28HT%5C+%3D%5C+0.911%5C%29%5C+was%5C+high.%5C+Population%5C+differentiation%5C+was%5C+also%5C+high%5C%28GST%5C+%3D%5C+0.846%2C%5C+NST%5C+%3D%5C+0.919%5C%29%2C%5C+indicating%5C+significant%5C+phylogeographical%5C+structure%5C+%5C%28NST%5C+%3E%5C+GST%2Cp%5C+%3C%5C+0.001%5C%29%5C+and%5C+low%5C+levels%5C+of%5C+seed%5C-based%5C+gene%5C+flow.%5C+C.%5C+debaoensis%5C+%5C%28Cycadaceae%5C%29%5C+is%5C+an%5C+endangered%5C+species%5C+restricted%5C+to%5C+the%5C+border%5C+of%5C+Guangxi%5C+and%5C+Yunnan%5C+province%5C+in%5C+southwest%5C+China.%5C+This%5C+species%5C+has%5C+been%5C+classified%5C+into%5C+two%5C+types%5C%3A%5C+sand%5C+and%5C+karst%2C%5C+according%5C+to%5C+the%5C+soil%5C+matrix%5C+they%5C+grow%5C+on.%5C+We%5C+examined%5C+chloroplast%5C+sequence%5C+variation%5C+of%5C+the%5C+cpDNA%5C+sequences%5C+from%5C+11%5C+populations%5C+of%5C+this%5C+species.%5C+Significant%5C+population%5C+genetic%5C+differentiation%5C+was%5C+detected%5C+%5C%28GST%3D%5C+0.684%5C+and%5C+FST%5C+%3D%5C+0.74160%5C%29.%5C+There%5C+was%5C+marked%5C+genetic%5C+differentiation%5C+between%5C+populations%5C+in%5C+the%5C+sand%5C+and%5C+karst%5C+regions%5C+and%5C+no%5C+expansion%5C+was%5C+detected.%5C+Climate%5C+changes%5C+during%5C+glacial%5C+periods%5C+have%5C+had%5C+significant%5C+effects%5C+on%5C+the%5C+current%5C+distribution%5C+of%5C+cycads.%5C+The%5C+molecular%5C+phylogenetic%5C+data%2C%5C+together%5C+with%5C+the%5C+geographic%5C+distribution%5C+of%5C+the%5C+haplotypes%2C%5C+suggest%5C+that%5C+C.%5C+debaoensis%5C+experienced%5C+range%5C+contraction%5C+during%5C+glacial%5C+periods%2C%5C+and%5C+that%5C+the%5C+current%5C+populations%5C+are%5C+still%5C+confined%5C+to%5C+the%5C+original%5C+refugia%5C+in%5C+southwest%5C+China%5C+which%5C+have%5C+favorable%5C+habitats%5C+in%5C+glacial%5C+period.%5C+These%5C+results%5C+imply%5C+that%5C+small%5C+refugia%5C+were%5C+maintained%5C+in%5C+both%5C+sand%5C+and%5C+karst%5C+regions%5C+during%5C+the%5C+LGM%5C+%5C%28last%5C+glacial%5C+maximum%5C%29.%5C+This%5C+species%5C+had%5C+no%5C+postglacial%5C+recolonization%5C+and%5C+only%5C+stayed%5C+in%5C+these%5C+refugia%5C+up%5C+to%5C+now.%5C+The%5C+low%5C+within%5C-population%5C+diversity%5C+of%5C+C.%5C+debaoensis%5C+suggests%5C+that%5C+there%5C+were%5C+strong%5C+bottleneck%5C+events%5C+or%5C+founder%5C+effects%5C+within%5C+each%5C+separate%5C+region%5C+during%5C+the%5C+Quaternary%5C+climatic%5C+oscillations.%5C+Relatively%5C+high%5C+genetic%5C+and%5C+haplotype%5C+diversities%5C+were%5C+detected%5C+in%5C+the%5C+newly%5C+discovered%5C+populations%2C%5C+which%5C+located%5C+at%5C+intermediate%5C+locality%5C+of%5C+sand%5C+regions%5C+and%5C+had%5C+morphological%5C+variation%5C%3B%5C+this%5C+is%5C+probably%5C+the%5C+consequence%5C+of%5C+the%5C+admixture%5C+of%5C+different%5C+haplotypes%5C+colonizing%5C+the%5C+area%5C+from%5C+separate%5C+sources.%5C+%5C+C.%5C+micholitzii%5C+occurs%5C+in%5C+the%5C+Annan%5C+Highlands%5C+in%5C+central%5C+Vietnam%5C+near%5C+the%5C+Laos%5C+border.%5C+C.%5C+bifida%5C+occurs%5C+in%5C+North%5C+Vietnam%5C%3B%5C+its%5C+distribution%5C+extends%5C+across%5C+the%5C+border%5C+into%5C+adjacent%5C+localities%5C+in%5C+Guangxi%5C+and%5C+Yunnan%5C+in%5C+China.%5C+For%5C+the%5C+comparability%5C+between%5C+them%2Ctheywere%5C+considered%5C+as%5C+the%5C+same%5C+species%5C+C.%5C+micholitzii%5C+by%5C+many%5C+academicians.%5C+The%5C+cpDNA%5C+sequences%5C+from%5C+11%5C+popul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stresses could limit plant growth, development and propagation. Abiotic stress refers to the negative impact factors to the plants, such as extreme temperature, drought, flood, salinity, irradiation, chemicals and so on. To understand the mechanism of abiotic stress is very important.Membrane is the most sensitive organs in the cell that response to environmental changes. Cells respond and transduct environmental signals by changing content of membrane lipids and membrane proteins. The activity change of membrane phospholipase D (PLD) and the composition and content of membrane lipid molecules is one of the most anti-stress methods for the plants. It was reported that plants responded to some abiotic stresses such as freezing, thawing, seed aging and dehydration through changing lipid molecules especially the messenger phosphatidic acid (PA) and mutants of PLD were more tolerant to those stresses. It is important to investigate the characteristics and variation of membrane lipids and membrane proteins to understand the streee in plants.Three different kinds of stresses, including alpine scree temperature stress, allelopathy and Gamma irradiation stress, were studied in the present dissertation. And try to understand how plants response to those stresses by changing membrane system and the function of PLD in resistant to those stresses, lipidomic methods were used to profiling the changing of 11 lipids classes (160 lipids molecules) under thoses stresses. Moreover, PLD mutants were also used to study the role of PLD under those stresses. The mechanisms of plants response to stresses were very complicated; PLD and lipid molecules were not the only factors that response to stresses, the metabolism and phytohormones of tested plants under these stresses were also studied.In alpine scree of northwest Yunnan, the temperature was various from 33 °C during the midday to 4 °C at night, and the highest temperature could reach to 35 to 40 °C. Saussurea medusa and Solms-Laubachia linearifolia, which live in this environment, were chosen as studied model. The results showed that membrane lipid of these two plants significantly fluctuated with the temperature, while the double bond index (DBI) that had close relationship to temperature did not change. Furthermore, the the lysolipids which rise significantly under stresses did not change too much either. Laboratory mimic experiments also confermed the characteristics of lipids change to temperature in alpine scree plants. The results suggested that the plants living in such temperature changeable environment had already adapted to this situation and their membrane responded to the temperature was a kind of adaptation instead of stress response.Since the first introduction in Yunnan province of China in 1940s, E. adenophorum has spread very rapidly especially in southwestern China. Without understanding its invasive mechanism, it is impossible to control it. o-Hydroxycinnamic acid (o-HCA), an allelochmeical isolated from leachates of aerial parts of E. adenophorum were studied. o-HCA was abundant in aerial parts of E. adenophorum (1g/10kg fresh weight). The data showed that o-HCA not only had strong allelopathic effect on Arabidopsis seeds germination, but also inhibited seedling growth, and even induced root death of Arabidopsis seedlings. It could be proposed that o-HCA affected seedlings indirectly, through inducing root cell death, and it disturbed the water and ion absorption of plants and finally induced seedling to die. Interestingly, o-HCA could also inhibit E. adenophorum seed germination, while it showed no effect on its seedling growth. E. adenophorum can produce thousands of seeds and has the ability to vegetative reproduction, with which may alleviate the harmful effect of o-HCA on E. adenophorum. Unlike E. adenophorum, its neighbors’ population was inhibited, under this situation, E. adenophorum coule have better condition to live and invade successfully.Arabidopsis were irradiated with gamma rays, and 50-100 Gy gamma irradiation could inhibit seedling growth, and with the dosage above 200 Gy it could inhibit seedling flowering. Treated Arabidopsis wild types and their PLD a and d mutant with gamma ray showed no significant differences among them. The lipid molecules changes of seedlings under stress of gamma ray were also tested, and found that Gamama ray induced lipids degradation, among which, MGDG and DGDG degraded dramatically, while the average carbons in lipids did not changed. The lipids content (nmol per mg dry weight) decreased significantly, while the mol% content (mol% of total) changed slightly. Gamma irradiation also leaded to dramatically change of Arabidopsis seedling metabolomics and the phytohormones (ABA，ZR，JA，IAA).","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Mutation&&fq=dc.project.title_filter%3AEnvironmental%5C+stresses%5C+could%5C+limit%5C+plant%5C+growth%2C%5C+development%5C+and%5C+propagation.%5C+Abiotic%5C+stress%5C+refers%5C+to%5C+the%5C+negative%5C+impact%5C+factors%5C+to%5C+the%5C+plants%2C%5C+such%5C+as%5C+extreme%5C+temperature%2C%5C+drought%2C%5C+flood%2C%5C+salinity%2C%5C+irradiation%2C%5C+chemicals%5C+and%5C+so%5C+on.%5C+To%5C+understand%5C+the%5C+mechanism%5C+of%5C+abiotic%5C+stress%5C+is%5C+very%5C+important.Membrane%5C+is%5C+the%5C+most%5C+sensitive%5C+organs%5C+in%5C+the%5C+cell%5C+that%5C+response%5C+to%5C+environmental%5C+changes.%5C+Cells%5C+respond%5C+and%5C+transduct%5C+environmental%5C+signals%5C+by%5C+changing%5C+content%5C+of%5C+membrane%5C+lipids%5C+and%5C+membrane%5C+proteins.%5C+The%5C+activity%5C+change%5C+of%5C+membrane%5C+phospholipase%5C+D%5C+%5C%28PLD%5C%29%5C+and%5C+the%5C+composition%5C+and%5C+content%5C+of%5C+membrane%5C+lipid%5C+molecules%5C+is%5C+one%5C+of%5C+the%5C+most%5C+anti%5C-stress%5C+methods%5C+for%5C+the%5C+plants.%5C+It%5C+was%5C+reported%5C+that%5C+plants%5C+responded%5C+to%5C+some%5C+abiotic%5C+stresses%5C+such%5C+as%5C+freezing%2C%5C+thawing%2C%5C+seed%5C+aging%5C+and%5C+dehydration%5C+through%5C+changing%5C+lipid%5C+molecules%5C+especially%5C+the%5C+messenger%5C+phosphatidic%5C+acid%5C+%5C%28PA%5C%29%5C+and%5C+mutants%5C+of%5C+PLD%5C+were%5C+more%5C+tolerant%5C+to%5C+those%5C+stresses.%5C+It%5C+is%5C+important%5C+to%5C+investigate%5C+the%5C+characteristics%5C+and%5C+variation%5C+of%5C+membrane%5C+lipids%5C+and%5C+membrane%5C+proteins%5C+to%5C+understand%5C+the%5C+streee%5C+in%5C+plants.Three%5C+different%5C+kinds%5C+of%5C+stresses%2C%5C+including%5C+alpine%5C+scree%5C+temperature%5C+stress%2C%5C+allelopathy%5C+and%5C+Gamma%5C+irradiation%5C+stress%2C%5C+were%5C+studied%5C+in%5C+the%5C+present%5C+dissertation.%5C+And%5C+try%5C+to%5C+understand%5C+how%5C+plants%5C+response%5C+to%5C+those%5C+stresses%5C+by%5C+changing%5C+membrane%5C+system%5C+and%5C+the%5C+function%5C+of%5C+PLD%5C+in%5C+resistant%5C+to%5C+those%5C+stresses%2C%5C+lipidomic%5C+methods%5C+were%5C+used%5C+to%5C+profiling%5C+the%5C+changing%5C+of%5C+11%5C+lipids%5C+classes%5C+%5C%28160%5C+lipids%5C+molecules%5C%29%5C+under%5C+thoses%5C+stresses.%5C+Moreover%2C%5C+PLD%5C+mutants%5C+were%5C+also%5C+used%5C+to%5C+study%5C+the%5C+role%5C+of%5C+PLD%5C+under%5C+those%5C+stresses.%5C+The%5C+mechanisms%5C+of%5C+plants%5C+response%5C+to%5C+stresses%5C+were%5C+very%5C+complicated%5C%3B%5C+PLD%5C+and%5C+lipid%5C+molecules%5C+were%5C+not%5C+the%5C+only%5C+factors%5C+that%5C+response%5C+to%5C+stresses%2C%5C+the%5C+metabolism%5C+and%5C+phytohormones%5C+of%5C+tested%5C+plants%5C+under%5C+these%5C+stresses%5C+were%5C+also%5C+studied.In%5C+alpine%5C+scree%5C+of%5C+northwest%5C+Yunnan%2C%5C+the%5C+temperature%5C+was%5C+various%5C+from%5C+33%5C+%C2%B0C%5C+during%5C+the%5C+midday%5C+to%5C+4%5C+%C2%B0C%5C+at%5C+night%2C%5C+and%5C+the%5C+highest%5C+temperature%5C+could%5C+reach%5C+to%5C+35%5C+to%5C+40%5C+%C2%B0C.%5C+Saussurea%5C+medusa%5C+and%5C+Solms%5C-Laubachia%5C+linearifolia%2C%5C+which%5C+live%5C+in%5C+this%5C+environment%2C%5C+were%5C+chosen%5C+as%5C+studied%5C+model.%5C+The%5C+results%5C+showed%5C+that%5C+membrane%5C+lipid%5C+of%5C+these%5C+two%5C+plants%5C+significantly%5C+fluctuated%5C+with%5C+the%5C+temperature%2C%5C+while%5C+the%5C+double%5C+bond%5C+index%5C+%5C%28DBI%5C%29%5C+that%5C+had%5C+close%5C+relationship%5C+to%5C+temperature%5C+did%5C+not%5C+change.%5C+Furthermore%2C%5C+the%5C+the%5C+lysolipids%5C+which%5C+rise%5C+significantly%5C+under%5C+stresses%5C+did%5C+not%5C+change%5C+too%5C+much%5C+either.%5C+Laboratory%5C+mimic%5C+experiments%5C+also%5C+confermed%5C+the%5C+characteristics%5C+of%5C+lipids%5C+change%5C+to%5C+temperature%5C+in%5C+alpine%5C+scree%5C+plants.%5C+The%5C+results%5C+suggested%5C+that%5C+the%5C+plants%5C+living%5C+in%5C+such%5C+temperature%5C+changeable%5C+environment%5C+had%5C+already%5C+adapted%5C+to%5C+this%5C+situation%5C+and%5C+their%5C+membrane%5C+responded%5C+to%5C+the%5C+temperature%5C+was%5C+a%5C+kind%5C+of%5C+adaptation%5C+instead%5C+of%5C+stress%5C+response.Since%5C+the%5C+first%5C+introduction%5C+in%5C+Yunnan%5C+province%5C+of%5C+China%5C+in%5C+1940s%2C%5C+E.%5C+adenophorum%5C+has%5C+spread%5C+very%5C+rapidly%5C+especially%5C+in%5C+southwestern%5C+China.%5C+Without%5C+understanding%5C+its%5C+invasive%5C+mechanism%2C%5C+it%5C+is%5C+impossible%5C+to%5C+control%5C+it.%5C+o%5C-Hydroxycinnamic%5C+acid%5C+%5C%28o%5C-HCA%5C%29%2C%5C+an%5C+allelochmeical%5C+isolated%5C+from%5C+leachates%5C+of%5C+aerial%5C+parts%5C+of%5C+E.%5C+adenophorum%5C+were%5C+studied.%5C+o%5C-HCA%5C+was%5C+abundant%5C+in%5C+aerial%5C+parts%5C+of%5C+E.%5C+adenophorum%5C+%5C%281g%5C%2F10kg%5C+fresh%5C+weight%5C%29.%5C+The%5C+data%5C+showed%5C+that%5C+o%5C-HCA%5C+not%5C+only%5C+had%5C+strong%5C+allelopathic%5C+effect%5C+on%5C+Arabidopsis%5C+se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Doctor Fund of Zhongkai University of Agriculture and Engineering[KA180581235]","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Mutation&&fq=dc.project.title_filter%3AExcellent%5C+Doctor%5C+Fund%5C+of%5C+Zhongkai%5C+University%5C+of%5C+Agriculture%5C+and%5C+Engineering%5C%5BKA180581235%5C%5D"},{"jsname":"Following the rapid uplift of the Himalaya, the reorganization of the major river drainages was primarily caused by river capture events，e.g. those of the Jinshajiang River (comprising the Upper, Middle and Lower Jinshajiang) and its tributaries (Yalongjiang, Daduhe, Jialingjiang), the Nujiang, the Lancangjiang, and the Honghe. We selected Terminalia franchetii var. franchetii and T. franchetii var. intricata in the Sino-Himalayan region to study the relationship with Honghe diversion events. The distribution of this species is predicted to have retained genetic signatures of past hydrological landscape structures. The major result as flowing:1. Chloroplast phylogeography of T. franchetii based on haplotype analysis，Based on a range-wide sampling comprising 28 populations and 258 individuals, and using chloroplast DNA sequences (trnL-trnF, petL-psbE), we detected 12 haplotypes. Terminalia franchetii was found to harbour high haplotype diversity (hT = 0.784) but low average within-population diversity (hS = 0.124). The analysis of genetic structure using SAMOVA showed that the number of population groups equaled five, and all the haplotypes can be divided into five groups. Group B and C identified exhibited a disjunctive distribution of dominant haplotypes between northern and southern valleys, corresponding to the geography of past rather than modern drainage systems.Mismatch distribution (multimodal curve) and neutral tests provided no evidence of recent demographic population growth. We suggest that the modern disjunctive distribution of T. franchetii, and associated patterns of cpDNA haplotype variation, result from vicariance caused by several historical river separation and capture events. By assuming a common mutation rate of the cpDNA-IGS regions, our inferred timings of these events (0.82-4.39 Mya) broadly agrees with both previous geological and molecular estimated time of drainage rearrangements in this region. So we conclude that there were several historical vicariance events play a major role for the distribution of T. franchetii in this region.2. Genetic diversity and structure of T. franchetii var. franchetii based on AFLP analysis，We determined the genotype of 251 individuals of T. franchetii var. franchetii from 21 populations using amplified fragment length polymorphism (AFLP), for our aim is only investigated the relationship between the modern distribution of T. franchetii and geological changes in drainage patterns. The overall estimate of genetic structure (Gst) was 0.249, indicating that clear genetic differentiation existed among the populations. Estimates of gene flow (Nm = 0.754) between populations based on the Gst value revealed that the number of migrants per generation is not frequently.Using Neighbor-Joining tree, Principal Coordinates Analysis, STRUCTURE and network methods, Analyses of AFLP markers identified two main population groups (I and II) and four subgroups (A – D) of T. franchetii. Genetic diversity was lower in Group I than in Group II. The results show that Groups I and II probably once occupied continuous areas respectively along ancient drainage systems and there were several historical separation and capture events that can account for the distribution of T. franchetii in this region. After all，these are good examples of the way in which historical events can change a species’ distribution from continuous to fragmented (Jinshajiang/ Yalongjiang and Honghe), and a disjunct distribution to a continuous one (Upper/Lower Jinshajiang and Yalongjiang). The results provide new insights into the phylogeographic pattern of plants in southwest China.3. Relationships between T. franchetii var. franchetii and T. franchetii var. intricata ，While T. franchetii var. Franchetii and var. intricata slightly differ in overall size and leaf hairiness, these taxa did not exhibit reciprocal monophyly. As results show, the genetic difference between the two varieties is much smaller than that within var. franchetii (Salween population vs. other populationsof this variety). It is also revealed in a phylogenetic analysis of ITS region of Combretoideae. The habitats of var. franchetii and var. intricata have obviously difference. Thus, the differences between the two varieties in overall size and leaf hairiness might reflect different phenotypic responses to environmental changes and the divergent environmental niche spaces they occupy. Based on the reasoning above, we agree with Flora of China that “T. intricata” represents a variety of T. franchetii rather than a separate species.","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Mutation&&fq=dc.project.title_filter%3AFollowing%5C+the%5C+rapid%5C+uplift%5C+of%5C+the%5C+Himalaya%2C%5C+the%5C+reorganization%5C+of%5C+the%5C+major%5C+river%5C+drainages%5C+was%5C+primarily%5C+caused%5C+by%5C+river%5C+capture%5C+events%EF%BC%8Ce.g.%5C+those%5C+of%5C+the%5C+Jinshajiang%5C+River%5C+%5C%28comprising%5C+the%5C+Upper%2C%5C+Middle%5C+and%5C+Lower%5C+Jinshajiang%5C%29%5C+and%5C+its%5C+tributaries%5C+%5C%28Yalongjiang%2C%5C+Daduhe%2C%5C+Jialingjiang%5C%29%2C%5C+the%5C+Nujiang%2C%5C+the%5C+Lancangjiang%2C%5C+and%5C+the%5C+Honghe.%5C+We%5C+selected%5C+Terminalia%5C+franchetii%5C+var.%5C+franchetii%5C+and%5C+T.%5C+franchetii%5C+var.%5C+intricata%5C+in%5C+the%5C+Sino%5C-Himalayan%5C+region%5C+to%5C+study%5C+the%5C+relationship%5C+with%5C+Honghe%5C+diversion%5C+events.%5C+The%5C+distribution%5C+of%5C+this%5C+species%5C+is%5C+predicted%5C+to%5C+have%5C+retained%5C+genetic%5C+signatures%5C+of%5C+past%5C+hydrological%5C+landscape%5C+structures.%5C+The%5C+major%5C+result%5C+as%5C+flowing%5C%3A1.%5C+Chloroplast%5C+phylogeography%5C+of%5C+T.%5C+franchetii%5C+based%5C+on%5C+haplotype%5C+analysis%EF%BC%8CBased%5C+on%5C+a%5C+range%5C-wide%5C+sampling%5C+comprising%5C+28%5C+populations%5C+and%5C+258%5C+individuals%2C%5C+and%5C+using%5C+chloroplast%5C+DNA%5C+sequences%5C+%5C%28trnL%5C-trnF%2C%5C+petL%5C-psbE%5C%29%2C%5C+we%5C+detected%5C+12%5C+haplotypes.%5C+Terminalia%5C+franchetii%5C+was%5C+found%5C+to%5C+harbour%5C+high%5C+haplotype%5C+diversity%5C+%5C%28hT%5C+%3D%5C+0.784%5C%29%5C+but%5C+low%5C+average%5C+within%5C-population%5C+diversity%5C+%5C%28hS%5C+%3D%5C+0.124%5C%29.%5C+The%5C+analysis%5C+of%5C+genetic%5C+structure%5C+using%5C+SAMOVA%5C+showed%5C+that%5C+the%5C+number%5C+of%5C+population%5C+groups%5C+equaled%5C+five%2C%5C+and%5C+all%5C+the%5C+haplotypes%5C+can%5C+be%5C+divided%5C+into%5C+five%5C+groups.%5C+Group%5C+B%5C+and%5C+C%5C+identified%5C+exhibited%5C+a%5C+disjunctive%5C+distribution%5C+of%5C+dominant%5C+haplotypes%5C+between%5C+northern%5C+and%5C+southern%5C+valleys%2C%5C+corresponding%5C+to%5C+the%5C+geography%5C+of%5C+past%5C+rather%5C+than%5C+modern%5C+drainage%5C+systems.Mismatch%5C+distribution%5C+%5C%28multimodal%5C+curve%5C%29%5C+and%5C+neutral%5C+tests%5C+provided%5C+no%5C+evidence%5C+of%5C+recent%5C+demographic%5C+population%5C+growth.%5C+We%5C+suggest%5C+that%5C+the%5C+modern%5C+disjunctive%5C+distribution%5C+of%5C+T.%5C+franchetii%2C%5C+and%5C+associated%5C+patterns%5C+of%5C+cpDNA%5C+haplotype%5C+variation%2C%5C+result%5C+from%5C+vicariance%5C+caused%5C+by%5C+several%5C+historical%5C+river%5C+separation%5C+and%5C+capture%5C+events.%5C+By%5C+assuming%5C+a%5C+common%5C+mutation%5C+rate%5C+of%5C+the%5C+cpDNA%5C-IGS%5C+regions%2C%5C+our%5C+inferred%5C+timings%5C+of%5C+these%5C+events%5C+%5C%280.82%5C-4.39%5C+Mya%5C%29%5C+broadly%5C+agrees%5C+with%5C+both%5C+previous%5C+geological%5C+and%5C+molecular%5C+estimated%5C+time%5C+of%5C+drainage%5C+rearrangements%5C+in%5C+this%5C+region.%5C+So%5C+we%5C+conclude%5C+that%5C+there%5C+were%5C+several%5C+historical%5C+vicariance%5C+events%5C+play%5C+a%5C+major%5C+role%5C+for%5C+the%5C+distribution%5C+of%5C+T.%5C+franchetii%5C+in%5C+this%5C+region.2.%5C+Genetic%5C+diversity%5C+and%5C+structure%5C+of%5C+T.%5C+franchetii%5C+var.%5C+franchetii%5C+based%5C+on%5C+AFLP%5C+analysis%EF%BC%8CWe%5C+determined%5C+the%5C+genotype%5C+of%5C+251%5C+individuals%5C+of%5C+T.%5C+franchetii%5C+var.%5C+franchetii%5C+from%5C+21%5C+populations%5C+using%5C+amplified%5C+fragment%5C+length%5C+polymorphism%5C+%5C%28AFLP%5C%29%2C%5C+for%5C+our%5C+aim%5C+is%5C+only%5C+investigated%5C+the%5C+relationship%5C+between%5C+the%5C+modern%5C+distribution%5C+of%5C+T.%5C+franchetii%5C+and%5C+geological%5C+changes%5C+in%5C+drainage%5C+patterns.%5C+The%5C+overall%5C+estimate%5C+of%5C+genetic%5C+structure%5C+%5C%28Gst%5C%29%5C+was%5C+0.249%2C%5C+indicating%5C+that%5C+clear%5C+genetic%5C+differentiation%5C+existed%5C+among%5C+the%5C+populations.%5C+Estimates%5C+of%5C+gene%5C+flow%5C+%5C%28Nm%5C+%3D%5C+0.754%5C%29%5C+between%5C+populations%5C+based%5C+on%5C+the%5C+Gst%5C+value%5C+revealed%5C+that%5C+the%5C+number%5C+of%5C+migrants%5C+per%5C+generation%5C+is%5C+not%5C+frequently.Using%5C+Neighbor%5C-Joining%5C+tree%2C%5C+Principal%5C+Coordinates%5C+Analysis%2C%5C+STRUCTURE%5C+and%5C+network%5C+methods%2C%5C+Analyses%5C+of%5C+AFLP%5C+markers%5C+identified%5C+two%5C+main%5C+population%5C+groups%5C+%5C%28I%5C+and%5C+II%5C%29%5C+and%5C+four%5C+subgroups%5C+%5C%28A%5C+%E2%80%93%5C+D%5C%29%5C+of%5C+T.%5C+franchetii.%5C+Genetic%5C+diversity%5C+was%5C+lower%5C+in%5C+Group%5C+I%5C+than%5C+in%5C+Group%5C+II.%5C+The%5C+results%5C+show%5C+that%5C+Groups%5C+I%5C+and%5C+II%5C+probably%5C+once%5C+occupied%5C+continuous%5C+areas%5C+respectively%5C+along%5C+ancient%5C+drainage%5C+systems%5C+and%5C+there%5C+were%5C+several%5C+historical%5C+separation%5C+and%5C+capture%5C+events%5C+that%5C+can%5C+accoun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has natural selection determined the evolution of gene regulation by acting on major regulatory factors? This question has been attractive to many evolutionary biologists for a long time. MicroRNAs (miRNAs) are endogenous posttranscriptional repressors and play essential roles in diverse biological processes in plants. To understand how natural selection has targeted on the entire lay of miRNA regulatory modules during flower development, we resequenced 31 miRNA target sites involved in flower development from five rice populations. We found that purifying selection serves as a major evolutionary force to act on the conserved miRNA binding sites, leading to the globally reduced genetic variation in highly conserved miRNA binding sequences within the entire rice samples. Conversely, positive selection allows variations at nonconserved miRNA binding sites and acts on them in a population-specific behaviour. Further analysis revealed that the polymorphisms within target sites may serve as raw materials for diverse functions of miRNAs by means of the destabilization of duplex, abolishment of existing target sites, and creation of novel ones. Together, the above-mentioned results indicate that variations at conserved binding sites are likely deleterious during rice flower development, whereas variants at nonconserved binding sites may be conductive to flower development-related phenotypic diversities and rice population adaption to variable environmental conditions as well. To further assess functional effects and evolutionary significance of variable alleles at the target genes, we reported the detailed characterization of the haplotype and linkage disequilibrium (LD) patterns of the entire target gene (LOC_Os01g18850，SPL 1) and the 1.4 Mb flanking regions in three rice populations, namely japonica, indica and O. rufipogon. The genetic profile of SNPs at target site and its flanking regions revealed high haplotype frequency, low haplotype diversity and strong LD in two cultivatedricepopulations. By contrast, we observed the opposite phenomena in O. rufipogon. Using the long-range haplotype (LRT) test, we found strong evidence of recent positive selection for SNP 3C/T alleles at target site in the combined O. sativa. Comparsion between the two rice subpopulations indicated that the major haplotype mh 2 containing SNP 3C accounts for half of all haplotypes in indica, while mh 3 containing SNP 3T is 91% in japonica. Moreover, the extent of LD is stronger in japonica than that in inidca. These differences suggest that independent evolutionary events may have occurred in target sequences of two cultivated rice populations and stronger positive selection acted on japonica. Next, we examined geographic distribution of polymorphic variants at target sites. We found that the major alleles SNP 3T and tightly linked SNP 4A in japonica appear to be associated with the adaption to the northern climates during rice flower development.","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Mutation&&fq=dc.project.title_filter%3AHow%5C+has%5C+natural%5C+selection%5C+determined%5C+the%5C+evolution%5C+of%5C+gene%5C+regulation%5C+by%5C+acting%5C+on%5C+major%5C+regulatory%5C+factors%5C%3F%5C+This%5C+question%5C+has%5C+been%5C+attractive%5C+to%5C+many%5C+evolutionary%5C+biologists%5C+for%5C+a%5C+long%5C+time.%5C+MicroRNAs%5C+%5C%28miRNAs%5C%29%5C+are%5C+endogenous%5C+posttranscriptional%5C+repressors%5C+and%5C+play%5C+essential%5C+roles%5C+in%5C+diverse%5C+biological%5C+processes%5C+in%5C+plants.%5C+To%5C+understand%5C+how%5C+natural%5C+selection%5C+has%5C+targeted%5C+on%5C+the%5C+entire%5C+lay%5C+of%5C+miRNA%5C+regulatory%5C+modules%5C+during%5C+flower%5C+development%2C%5C+we%5C+resequenced%5C+31%5C+miRNA%5C+target%5C+sites%5C+involved%5C+in%5C+flower%5C+development%5C+from%5C+five%5C+rice%5C+populations.%5C+We%5C+found%5C+that%5C+purifying%5C+selection%5C+serves%5C+as%5C+a%5C+major%5C+evolutionary%5C+force%5C+to%5C+act%5C+on%5C+the%5C+conserved%5C+miRNA%5C+binding%5C+sites%2C%5C+leading%5C+to%5C+the%5C+globally%5C+reduced%5C+genetic%5C+variation%5C+in%5C+highly%5C+conserved%5C+miRNA%5C+binding%5C+sequences%5C+within%5C+the%5C+entire%5C+rice%5C+samples.%5C+Conversely%2C%5C+positive%5C+selection%5C+allows%5C+variations%5C+at%5C+nonconserved%5C+miRNA%5C+binding%5C+sites%5C+and%5C+acts%5C+on%5C+them%5C+in%5C+a%5C+population%5C-specific%5C+behaviour.%5C+Further%5C+analysis%5C+revealed%5C+that%5C+the%5C+polymorphisms%5C+within%5C+target%5C+sites%5C+may%5C+serve%5C+as%5C+raw%5C+materials%5C+for%5C+diverse%5C+functions%5C+of%5C+miRNAs%5C+by%5C+means%5C+of%5C+the%5C+destabilization%5C+of%5C+duplex%2C%5C+abolishment%5C+of%5C+existing%5C+target%5C+sites%2C%5C+and%5C+creation%5C+of%5C+novel%5C+ones.%5C+Together%2C%5C+the%5C+above%5C-mentioned%5C+results%5C+indicate%5C+that%5C+variations%5C+at%5C+conserved%5C+binding%5C+sites%5C+are%5C+likely%5C+deleterious%5C+during%5C+rice%5C+flower%5C+development%2C%5C+whereas%5C+variants%5C+at%5C+nonconserved%5C+binding%5C+sites%5C+may%5C+be%5C+conductive%5C+to%5C+flower%5C+development%5C-related%5C+phenotypic%5C+diversities%5C+and%5C+rice%5C+population%5C+adaption%5C+to%5C+variable%5C+environmental%5C+conditions%5C+as%5C+well.%5C+To%5C+further%5C+assess%5C+functional%5C+effects%5C+and%5C+evolutionary%5C+significance%5C+of%5C+variable%5C+alleles%5C+at%5C+the%5C+target%5C+genes%2C%5C+we%5C+reported%5C+the%5C+detailed%5C+characterization%5C+of%5C+the%5C+haplotype%5C+and%5C+linkage%5C+disequilibrium%5C+%5C%28LD%5C%29%5C+patterns%5C+of%5C+the%5C+entire%5C+target%5C+gene%5C+%5C%28LOC_Os01g18850%EF%BC%8CSPL%5C+1%5C%29%5C+and%5C+the%5C+1.4%5C+Mb%5C+flanking%5C+regions%5C+in%5C+three%5C+rice%5C+populations%2C%5C+namely%5C+japonica%2C%5C+indica%5C+and%5C+O.%5C+rufipogon.%5C+The%5C+genetic%5C+profile%5C+of%5C+SNPs%5C+at%5C+target%5C+site%5C+and%5C+its%5C+flanking%5C+regions%5C+revealed%5C+high%5C+haplotype%5C+frequency%2C%5C+low%5C+haplotype%5C+diversity%5C+and%5C+strong%5C+LD%5C+in%5C+two%5C+cultivatedricepopulations.%5C+By%5C+contrast%2C%5C+we%5C+observed%5C+the%5C+opposite%5C+phenomena%5C+in%5C+O.%5C+rufipogon.%5C+Using%5C+the%5C+long%5C-range%5C+haplotype%5C+%5C%28LRT%5C%29%5C+test%2C%5C+we%5C+found%5C+strong%5C+evidence%5C+of%5C+recent%5C+positive%5C+selection%5C+for%5C+SNP%5C+3C%5C%2FT%5C+alleles%5C+at%5C+target%5C+site%5C+in%5C+the%5C+combined%5C+O.%5C+sativa.%5C+Comparsion%5C+between%5C+the%5C+two%5C+rice%5C+subpopulations%5C+indicated%5C+that%5C+the%5C+major%5C+haplotype%5C+mh%5C+2%5C+containing%5C+SNP%5C+3C%5C+accounts%5C+for%5C+half%5C+of%5C+all%5C+haplotypes%5C+in%5C+indica%2C%5C+while%5C+mh%5C+3%5C+containing%5C+SNP%5C+3T%5C+is%5C+91%25%5C+in%5C+japonica.%5C+Moreover%2C%5C+the%5C+extent%5C+of%5C+LD%5C+is%5C+stronger%5C+in%5C+japonica%5C+than%5C+that%5C+in%5C+inidca.%5C+These%5C+differences%5C+suggest%5C+that%5C+independent%5C+evolutionary%5C+events%5C+may%5C+have%5C+occurred%5C+in%5C+target%5C+sequences%5C+of%5C+two%5C+cultivated%5C+rice%5C+populations%5C+and%5C+stronger%5C+positive%5C+selection%5C+acted%5C+on%5C+japonica.%5C+Next%2C%5C+we%5C+examined%5C+geographic%5C+distribution%5C+of%5C+polymorphic%5C+variants%5C+at%5C+target%5C+sites.%5C+We%5C+found%5C+that%5C+the%5C+major%5C+alleles%5C+SNP%5C+3T%5C+and%5C+tightly%5C+linked%5C+SNP%5C+4A%5C+in%5C+japonica%5C+appear%5C+to%5C+be%5C+associated%5C+with%5C+the%5C+adaption%5C+to%5C+the%5C+northern%5C+climates%5C+during%5C+rice%5C+flower%5C+development."},{"jsname":"In Chapter 1, we isolated a flavonoid prenyltransferase-like gene from traditional Chinese medicinal herb, Epimedium L. (berberidaceae). Epimedium species have a high content of the prenylated flavonol glycosides. Icariin and epimedin A, B and C are frequently used as marker compounds for the quality control of Epimedium. Here we speculate prenyl flavonoids biosynthesis pathway in Epimedium: The flavonoid prenyltransferase is responsible for the prenylation of flavonoids (naringenin 、kaempferol or apigenin) at the 8-position or 3'' or 5''-position. Leaves of Epimedium acuminatum Franch in the nursery were collected every month, and then detected the icariin content. The results show that leaves in March have the highest icariin content. Total RNA was extracted from leaves in March as template. A similarity-based cloning strategy yielded a flavonoid prenyltransferase-like gene, named EaPT1. In E. coli. expression system, pET32a(+) was chosen as the expression vector for use in Rosetta-gamiB(DE3)、RosettaTM 2（DE3）plysS、BL21(DE3)plysE、BL21(DE3)gold and BL21(DE3) cells. The full length ORF and truncated sequence were ligated with pET32a(+). We did not detect the target protein in SDS-PAGE. In Saccharomyces cerevisiae expression system, the full length ORF was ligated with pYES2. In this expression system, we still could not detect the protein in SDS-PAGE. LC/MS did not detect the activity of prenyltransferase, with naringenin as substrate. Chapter 2 describes functional expression and characterization of two copalyl pyrophosphate synthase gene from Isodon ericalyx (Dunn) Kudo, named IeCPS7 and IeCPS11. Their full length ORF and truncated sequence were ligated into pET32a(+). These vectors were used to transform E.coli BL21(DE)3. The truncated IeCPS7 sequence expressed a soluble His-tag recombinant protein, 104699.41D, pI5.87, 924aa. The recombinant protein was characterized for diterpene synthase activity by using geranylgeranyl diphosphate(GGPP) as substrates and subsequent GC/MS analysis of products. The purified recombinant IeCPS showed optimum activity at pH7.1. In addition, IeCPS showed maximum activity at 30℃. The enzymatic activity was increased by addition of MgCl2 to the reaction mixture. Unexpectedly, MnCl2 actually inhibited the enzyme activity. In addition,only insoluble recombinant proteins were expressed for IeCPS11 in BL21(DE)3, Rosetta-gamiB(DE3) and RosettaTM 2（DE3）plysS. The last part reviews the advances in molecular studies of aromatic prenyltransferase in plants and fungi, focusing on membrane-bound homogentisate prenyltransferses, flavonoid prenyltransferases as well as soluble indole prenyltransferases.","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Mutation&&fq=dc.project.title_filter%3AIn%5C+Chapter%5C+1%2C%5C+we%5C+isolated%5C+a%5C+flavonoid%5C+prenyltransferase%5C-like%5C+gene%5C+from%5C+traditional%5C+Chinese%5C+medicinal%5C+herb%2C%5C+Epimedium%5C+L.%5C+%5C%28berberidaceae%5C%29.%5C+Epimedium%5C+species%5C+have%5C+a%5C+high%5C+content%5C+of%5C+the%5C+prenylated%5C+flavonol%5C+glycosides.%5C+Icariin%5C+and%5C+epimedin%5C+A%2C%5C+B%5C+and%5C+C%5C+are%5C+frequently%5C+used%5C+as%5C+marker%5C+compounds%5C+for%5C+the%5C+quality%5C+control%5C+of%5C+Epimedium.%5C+Here%5C+we%5C+speculate%5C+prenyl%5C+flavonoids%5C+biosynthesis%5C+pathway%5C+in%5C+Epimedium%5C%3A%5C+The%5C+flavonoid%5C+prenyltransferase%5C+is%5C+responsible%5C+for%5C+the%5C+prenylation%5C+of%5C+flavonoids%5C+%5C%28naringenin%5C+%E3%80%81kaempferol%5C+or%5C+apigenin%5C%29%5C+at%5C+the%5C+8%5C-position%5C+or%5C+3%27%27%5C+or%5C+5%27%27%5C-position.%5C+Leaves%5C+of%5C+Epimedium%5C+acuminatum%5C+Franch%5C+in%5C+the%5C+nursery%5C+were%5C+collected%5C+every%5C+month%2C%5C+and%5C+then%5C+detected%5C+the%5C+icariin%5C+content.%5C+The%5C+results%5C+show%5C+that%5C+leaves%5C+in%5C+March%5C+have%5C+the%5C+highest%5C+icariin%5C+content.%5C+Total%5C+RNA%5C+was%5C+extracted%5C+from%5C+leaves%5C+in%5C+March%5C+as%5C+template.%5C+A%5C+similarity%5C-based%5C+cloning%5C+strategy%5C+yielded%5C+a%5C+flavonoid%5C+prenyltransferase%5C-like%5C+gene%2C%5C+named%5C+EaPT1.%5C+In%5C+E.%5C+coli.%5C+expression%5C+system%2C%5C+pET32a%5C%28%5C%2B%5C%29%5C+was%5C+chosen%5C+as%5C+the%5C+expression%5C+vector%5C+for%5C+use%5C+in%5C+Rosetta%5C-gamiB%5C%28DE3%5C%29%E3%80%81RosettaTM%5C+2%EF%BC%88DE3%EF%BC%89plysS%E3%80%81BL21%5C%28DE3%5C%29plysE%E3%80%81BL21%5C%28DE3%5C%29gold%5C+and%5C+BL21%5C%28DE3%5C%29%5C+cells.%5C+The%5C+full%5C+length%5C+ORF%5C+and%5C+truncated%5C+sequence%5C+were%5C+ligated%5C+with%5C+pET32a%5C%28%5C%2B%5C%29.%5C+We%5C+did%5C+not%5C+detect%5C+the%5C+target%5C+protein%5C+in%5C+SDS%5C-PAGE.%5C+In%5C+Saccharomyces%5C+cerevisiae%5C+expression%5C+system%2C%5C+the%5C+full%5C+length%5C+ORF%5C+was%5C+ligated%5C+with%5C+pYES2.%5C+In%5C+this%5C+expression%5C+system%2C%5C+we%5C+still%5C+could%5C+not%5C+detect%5C+the%5C+protein%5C+in%5C+SDS%5C-PAGE.%5C+LC%5C%2FMS%5C+did%5C+not%5C+detect%5C+the%5C+activity%5C+of%5C+prenyltransferase%2C%5C+with%5C+naringenin%5C+as%5C+substrate.%5C+Chapter%5C+2%5C+describes%5C+functional%5C+expression%5C+and%5C+characterization%5C+of%5C+two%5C+copalyl%5C+pyrophosphate%5C+synthase%5C+gene%5C+from%5C+Isodon%5C+ericalyx%5C+%5C%28Dunn%5C%29%5C+Kudo%2C%5C+named%5C+IeCPS7%5C+and%5C+IeCPS11.%5C+Their%5C+full%5C+length%5C+ORF%5C+and%5C+truncated%5C+sequence%5C+were%5C+ligated%5C+into%5C+pET32a%5C%28%5C%2B%5C%29.%5C+These%5C+vectors%5C+were%5C+used%5C+to%5C+transform%5C+E.coli%5C+BL21%5C%28DE%5C%293.%5C+The%5C+truncated%5C+IeCPS7%5C+sequence%5C+expressed%5C+a%5C+soluble%5C+His%5C-tag%5C+recombinant%5C+protein%2C%5C+104699.41D%2C%5C+pI5.87%2C%5C+924aa.%5C+The%5C+recombinant%5C+protein%5C+was%5C+characterized%5C+for%5C+diterpene%5C+synthase%5C+activity%5C+by%5C+using%5C+geranylgeranyl%5C+diphosphate%5C%28GGPP%5C%29%5C+as%5C+substrates%5C+and%5C+subsequent%5C+GC%5C%2FMS%5C+analysis%5C+of%5C+products.%5C+The%5C+purified%5C+recombinant%5C+IeCPS%5C+showed%5C+optimum%5C+activity%5C+at%5C+pH7.1.%5C+In%5C+addition%2C%5C+IeCPS%5C+showed%5C+maximum%5C+activity%5C+at%5C+30%E2%84%83.%5C+The%5C+enzymatic%5C+activity%5C+was%5C+increased%5C+by%5C+addition%5C+of%5C+MgCl2%5C+to%5C+the%5C+reaction%5C+mixture.%5C+Unexpectedly%2C%5C+MnCl2%5C+actually%5C+inhibited%5C+the%5C+enzyme%5C+activity.%5C+In%5C+addition%2Conly%5C+insoluble%5C+recombinant%5C+proteins%5C+were%5C+expressed%5C+for%5C+IeCPS11%5C+in%5C+BL21%5C%28DE%5C%293%2C%5C+Rosetta%5C-gamiB%5C%28DE3%5C%29%5C+and%5C+RosettaTM%5C+2%EF%BC%88DE3%EF%BC%89plysS.%5C+The%5C+last%5C+part%5C+reviews%5C+the%5C+advances%5C+in%5C+molecular%5C+studies%5C+of%5C+aromatic%5C+prenyltransferase%5C+in%5C+plants%5C+and%5C+fungi%2C%5C+focusing%5C+on%5C+membrane%5C-bound%5C+homogentisate%5C+prenyltransferses%2C%5C+flavonoid%5C+prenyltransferases%5C+as%5C+well%5C+as%5C+soluble%5C+indole%5C+prenyltransferases."},{"jsname":"Kunming Institute of Botany[KIB2017003]","jscount":"1","jsurl":"/simple-search?field1=all&field=dc.citation.source_filter&advanced=false&query1=Mutation&&fq=dc.project.title_filter%3AKunming%5C+Institute%5C+of%5C+Botany%5C%5BKIB2017003%5C%5D"},{"jsname":"lastIndexed","jscount":"2024-07-09"}],"资助项目","dc.project.title_filter")'>
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