摘要
以山茶属9个组9个物种的叶绿体基因组(chloroplast genome DNA, cpDNA)全序列为研究对象,统计分析其简单重复序列(chloroplast simple sequence repeat, cpSSR)或称微卫星分布特征。结果表明山茶属各物种cpSSR数量及组成相对一致,不同微卫星重复基序中以三核苷酸基序为主,平均约占70%,随后是单核苷酸及二核苷酸基序。各物种单核苷酸和三核苷酸重复碱基类型较为一致,分别为A/T和AAG/TTC。比较叶绿体基因组的不同结构位置,各物种总的表现规律为小单拷贝区(small single copy, SSC) cpSSR分布比例最高,而反向重复区(inverted repeat, IR)最低;同时比较叶绿体基因组的不同功能区域,山茶属各物种的cpSSR主要分布于非编码区。cpSSR种间变异分析表明,cpSSR在山茶属内各组物种间差异较小,整体保持一个较高的一致性,说明山茶属是一个亲缘关系较近的属。对重复基序类型来说,单核苷酸重复基序cpSSR的变异率最高;在各结构域中,cpSSR在大单拷贝区(large single copy, LSC)的变异最大,变异比例占63.46%;而对功能区域来说,非编码区分布的cpSSR的变异率则高于编码区。研究同时建立了山茶属cpSSR分子标记体系,初步筛选出在种间具有较好多态性的cpSSR标记。本研究为今后山茶属多态性的cpSSR标记开发及应用提供重要的理论依据与物质基础。
In this study, the complete chloroplast genome DNA （cpDNA） sequences of 9 species of the 9 genus Camellia were used as the research object, and the distribution characteristics of chloroplast simple sequence repeat （cpSSRs） or called as microsatellite were analyzed statistically. The results indicated that the quantity and composition of cpSSRs of all species were relatively consistent, about 70% of the repeat motifs were the trinucleotide motifs, and then mononucleotide motifs and dinucleotide repeat motifs. The main base in the mononucleotide and trinucleotide repetitive types were consistent in all species, they were A/T and AAG/TTC, respectively. The comparison of different chloroplast genome structures showed the distribution proportion of cpSSRs was the highest in the small single copy （SSC） region and the lowest in the inverted repeat （IR） region. Meanwhile, the comparison of different fimctional regions showed that the distribution proportion was the highest in the non-coding region. The interspecific variation of cpSSRs showed little diversity among the genus Camellia and it maintained higher level of consistency in whole, which indicated that the genus Camellia had a close relationship. For the types of repetitive motifs, mononucleotide motif had the highest mutation rate. The variation rate of cpSSRs in the large single copy （LSC） region was the highest, which accounted for 63.46%. And for the functional regions of chloroplast genome, the variation rate of cpSSRs in the non-coding region was higher than that in the coding region. Meanwhile, the molecular marker system of cpSSRs in the genus Camellia was established in this study, and the cpSSRs markers that had a good interspecific polymorphism were preliminarily screened. This research would lay an important theoretical and material basis for the development of large amounts ofpolymorphic cpSSR markers in genus Camellia in the future.
作者
殷鑫
温强
王建文
李田
叶金山
徐立安
Yin Xin;Wen Qiang;Wang Jianwen;Li Tian;Ye Jinshan;Xu Li＇an(Co-Innovation Center for Sustainable Forestry in Southern China,Nanjing Forestry University,Nanjing,210037;Jiangxi Provincial Key Laboratory for Plant Biotechnology,Jiangxi Academy of Forestry,Nanchang,330013)
出处
《分子植物育种》
CAS
CSCD
北大核心
2018年第20期6761-6769,共9页
Molecular Plant Breeding
基金
国家自然科学基金项目(31860179
31260184)
江西省自然科学基金项目(20151BAB204030)
江西省科技支撑重点项目(2016IBBF60122)
江西省科技支撑项目(20122BBF60125)
江西省林业科学院青年培养项目(2016521101)
江苏高校优势学科项目(PAPD)共同资助
