【摘要】 荠菜属植物是十字花科中分布较广泛的植物,其中四倍体荠菜(Capsella bursa-pastoris)是一种由祖先二倍体亲本杂交再经多倍化后形成的多倍体物种,在地域分布及多样化的逆境适应能力方面与其祖先亲本相比具有明显优势,目前四倍体荠菜对于环境适应性的研究报道还不多见.植物钙/阳离子逆转运蛋白超家族(CaCAs)是一类膜定位的离子转运蛋白,在植物抗冷、抗盐等信号通路中起到重要作用.本研究通过生物信息学及表达谱分析手段,发现四倍体荠菜CaCAs的13对亚基因组基因中有4对出现了拷贝数变异,其中3对基因在其编码的氨基酸序列和蛋白质跨膜结构方面与其直系同源基因间存在较大差异,且在冷响应表达上与拟南芥相比出现了明显偏倚.此外,与四倍体荠菜的祖先亲本Capsella rubella相比,四倍体荠菜CaCAs基因的组织表达分化较为普遍.CaCAs基因在四倍体荠菜中的拷贝数变异和表达分化现象提示了CaCAs对植物环境适应性的贡献.更多还原

【Abstract】 Capsella bursa-pastoris is a polyploid species formed by multiplication of ancestral diploid parents.It has obvious advantages compared with its ancestral parents in geographical distribution and adaptability to multiple stress conditions.At present,there is limited research on the origin of environmental adaptability of C.bursapastoris.Plant calcium/cation anti-transporter superfamily(CaCAs)are a class of membrane-localized ion transporters that play important roles in plant cold and salt resistance signaling pathways.Through bioinformatics and expression profiling,this study revealed that 4 pairs of 13 pairs of subgenomic genes of C.bursa-pastoris CaCAs have copy number variations.Among the 4 pairs of subgenomic genes,three pairs of genes have large differences from their orthologous in amino acid sequence and protein transmembrane structure,and there is a significant bias in cold response expression compared with Arabidopsis thaliana.In addition,the differentiation in tissue expression of CaCAs genes is common between Cb.ursa-pastoris and its ancestral parent Cr.ubella.These results prompt the contribution of CaCAs to plant environmental adaptability.更多还原