【摘要】 以矮牵牛的cDNA核苷酸序列为基础,利用杨树EST数据库和毛果杨基因组测序结果,通过序列的拼接设计合成了基因特异引物,从毛白杨形成层cDNA中扩增出一个长为1 009 bp的cDNA片段,将该片段连接到pGEM-T载体中并测序。测序结果表明,该片段含有完整的开放阅读框,共编码258个氨基酸残基。蛋白序列系统进化分析结果表明,该基因属于exp ansin基因家族-αexp ansin中的A亚家族,编码的氨基酸序列与芒果、欧洲山杨×美洲山杨杂交种、拟南芥和矮牵牛的-αexp ansin基因编码的氨基酸序列同源性分别为91%,88%,86%和86%。更多还原

【Abstract】 Expansin is a protein responsible for the extension of cell walls leading to the enlargement of the plant cell.Many genes encoding for expansins have been isolated in different plant species.In this study,the PtEXP1 cDNA was amplified from the cambium of Populus tomentosa Carr.by the RT-PCR technique using gene-specific primers designed according to the Populus EST and P.trichocarpa genomic sequences using Petunia hybrida cDNA sequence as the starting information.Sequence analysis showed that this cDNA was 1 009 bp in length capable of encoding 258 amino acids and 91%,88%,86%,86% homology were found with Mangifera indica,P.tremula×P.tremulides,Arabidopsis thaliana,Petunia hybrida,respectively.PtEXP1 was subclassed into Subgroup A of the α-expansin gene family.更多还原