籼稻胚乳特异性启动子Gt1的克隆及其功能验证

Isolation of Endosperm-specific Promoter Gt1 from Indica Rice and Verification of Its Function in Transgenic Rice

从籼稻(Oryzasativa L.ssp.indica)品种谷秆两用稻‘东南201’中克隆获得胚乳特异性启动子Gt1;序列全长为929 bp;含胚乳中特异表达所必需的正调控元件GCN4 motif(TGAGTCA)与Skn-1 motif(GT-CAT)等。与已报道的粳稻品种‘日本晴’的序列相比,籼稻‘东南201’Gt1启动子序列仅在-507 bp处发生一个碱基突变,在-268、-267、-194、-193 bp位置处分别缺失1个碱基;但在已知功能motif,两者没有任何差异。用Gt1替代35SCa MV启动子驱动GUS基因转化水稻‘台粳9号’,结果表明GUS基因仅在胚乳中特异表达,而在其它组织中未表达。克隆的籼稻谷蛋白基因Gt1的启动子序列,可为进一步开展水稻品质分子改良提供必要手段。

The rice endosperm-specific promoter Gt1 was cloned from indica variety rice 'DN201',a special grain-straw-dual-use-rice,and the sequence has been deposited into GenBank under accession No.EU441217.Complete nucleotide sequence of Gt1 was 929 bp(including 35 bp 5' UTR).The cis-regulatory elements,GCN4 motif(TGAGTCA) and Skn-1 motif(GTCAT),which were required for endosperm-specific expression,were identified in the sequence.Except that there is a mutation(-507 bp) and four lacked bases(-268 bp,-267 bp,-194 bp,-193 bp) occurred in Gt1 promoter of 'DN201' when compared with previously reported 'Nipponbare',a Japonica rice variety,no significance differed in important functiona1 regions between these two sequences.The cloned promoter Gt1 was transformed in rice 'Taijing No.9' for its functional verification by replacing CaMV35S promoter and driving the expression of GUS gene.GUS activities in various tissues of transformed plants were examined and the results showed that GUS gene was only specifically expression expressed in rice endosperm.Isolation of endosperm-specific promoter Gt1 from indica rice 'DN201' provide one way for molecular genetic improvement on rice qualitative traits.