【摘要】 在前期构建的富集丰磷逆境特异表达小麦根系cDNA差减文库中,鉴定了1个SPX家族基因成员TaSPX129(GenBank登录号:EF522137)。TaSPX129的开放阅读框为1 320bp,编码一条由439个氨基酸残基组成的蛋白质多肽链,该预测蛋白中含有植物保守的SPX基序。系统进化分析表明,TaSPX129与大麦和二穗短柄草的SPX基因具有较高同源性,推测上述基因可能具有相似的进化途径。对TaSPX129与其他植物种属中的同源蛋白进行聚类分析,该小麦SPX成员属于SPX-MFS亚家族。与丰磷对照相比,低磷处理后小麦根系中TaSPX129的表达水平下降。此外,TaSPX129对低氮和高盐逆境也明显应答,表现为根系中该基因的表达水平明显下降。本研究表明,TaSPX129在转录水平上对低磷等逆境产生应答,为探索该基因介导植株抵御非生物胁迫的机制打下基础。更多还原

【Abstract】 ASPXtype gene designated as TaSPX129(GenBank accession number EF522137)was identified in a Subtractive Suppression Hybridization cDNA library of wheat root enriched with differentially expressed genes under Pi sufficiency.TaSPX129 contains an open reading frame of 1320 bp that encodes a polypeptide with 439 amino acids.The deduced protein shares one conserved SPX motif.Phylogenetic analysis suggesed that TaSPX129 exhibits a high similarity to its homologous partners in Hordeum vulgare and Brachypodium distachyon,which indicated that similar evolutionary pathways exist among them.Structural clustering analysis showed that the deduced TaSPX129 belongs to the SPX-MFS subfamily.Compared with that under Pi sufficiency,the expression level of TaSPX129 in wheat roots was significantlyreduced under Pi deprivation.In addition,TaSPX129 also showed response to stresses of N deprivation and high salinity,and its expression level in wheat roots decreased dramatically under above treatments.Thus,our results provided experimental basis for exploring the gene mediated plant resistance mechanism under abiotic stress through the transcriptional response of TaSPX129 to these stressors.更多还原