【摘要】 以20种高等植物SOD基因编码区序列(CDS)为参考,进行基因流特性与亲缘关系分析.通过下载20个物种SOD基因的完整CDS序列,并分析其单倍型数、单倍型多样性、核苷酸多样性、平均核苷酸差异数目及单一多态位点和简约多态位点等信息,建立系统进化树;分析其氨基酸结构域并预测跨膜结构域;再分析SOD基因所编码蛋白质的氨基酸数量、组成及部分理化性质.研究结果表明:SOD基因在种内及种间遗传分化较明显.由系统进化树可知,各物种种间的遗传进化关系与植物分类学中的分类基本一致.结构域预测得大部分序列具有一个保守的结构域SOD-Cu,个别序列含SOD-Fe-N结构域和SOD-Fe-C结构域.理化性质预测得不同物种SOD蛋白的性质和氨基酸数量较稳定,蛋白质呈酸性,具有亲水性.本研究为进一步探索SOD基因的生物学功能和以该基因作为分子标记进行物种定向选育提供了重要参考.更多还原

【Abstract】 The gene flow and relationship of higher plants were studied with the SOD gene coding sequences(CDS)20 species downloaded from the genbank. The number of haplotypes,haplotype diversity,nucleotide divergence,average number of nucleotide differences,singleton variable sites and parsimony informative polymorphic sites of these sequences were analyzed in this paper. Then was red the system tree. Domain of amino acid structure was analyzed and the crossmembrane domain was predicted. The number, composition and some physical and chemical properties of amino acids encoded by SOD gene were analyzed.The results showed that the genetic differentiation of SOD gene was more obvious in intraspecific and interspecific analysis. Based on the system tree,we found that the genetic and evolutionary relationship between each species was basically consistent with the classification in plant taxonomy. According to the domain prediction,we found that most SOD sequences have a conserve domain SOD-Cu,some contain SOD-Fe-N and SODFe-C. The prediction results of physical and chemical properties show that the number of amino acids and protein properties were stable and the proteins were acidic and hydrophilic. This study provides an important reference for further exploration of the biological function of SOD gene and the use of this gene as a molecular marker for targeted species selection.更多还原