为研究40S核糖体蛋白S15a(ribosomal proteinS15a,RPS15a)在小麦多子房性状形成过程中的功能作用,以小麦(Triticum aestivum)多子房近等基因系构建的多子房性状SSH-cDNA文库中与RPS15a基因同源的EST序列为信息探针,采用RT-PCR技术从小麦多子房株系幼穗中克隆获得了RPS15a基因的cDNA与DNA序列,分析了该基因在近等基因系间的表达差异及其在多子房株系中不同时期幼穗和同一发育时期不同组织中的表达模式。结果表明,小麦RPS15a基因的cDNA序列(GenBank登录号:HM055513)长为413bp,编码131个氨基酸;DNA序列(GenBank登录号:HM063421)长为642bp,含有3个外显子和2个内含子。半定量RT-PCR分析显示,该基因在多子房株系2~4mm幼穗中的表达量高于单子房株系幼穗;在多子房株系不同时期幼穗中的表达量随着幼穗的发育呈现上升趋势,8~9mm时表达量达到最高;该基因广泛存在于幼根、茎顶端、幼叶和幼穗组织中,在茎顶端表达量高于其他组织。研究推测RPS15a基因的表达上调,可能与小麦多子房性状的发生有关。
To study the effect of 40S ribosomal protein S15a(RPS15a) on the formation of multi-ovary in wheat,the EST highly similar to RPS15a gene from the multi-ovary SSH-cDNA library was used as a query probe to blastn the GenBank databases.Based on the assembled homologous cDNA sequence,both cDNA and DNA sequences encoding a RPS15a were isolated and characterized from multi-ovary line by RT-PCR.Furthermore,expression patterns of the gene in different material,different development stages of ears in multi-ovary line and different tissues of multi-ovary line were analyzed by semi-quantitative RT-PCR.Results showed that the cDNA sequence(GenBank accession No.HM055513) was 413 bp in length and the open reading frame encoded a peptide of 131 amino acids.The DNA sequence(GenBank accession No.HM063421) was 642 bp in length,which contained three extrons and two introns.According to expression analysis,the expression of the gene in 2~4 mm ears of multi-ovary line was higher than that in mono-ovary line.This gene was upregulated with the development of young ear,and the highest levels of expression at period of 8~9 mm.Besides,the gene was expressed in various tissues and relatively higher at the stem shoot meristem than that of other parts examined.Thus conclusively the RPS15a gene is differentially expressed in multi-ovary and mono-ovary lines and may involve in the information of multi-ovary.