编码水稻胞外核苷酸双磷酸酶基因的表达特性

Expression Characteristics of Extracellular Nucleoside Triphosphate-diphosphohydrolases Gene in Oryza sativa

NTPDase(Nucleoside triphosphate-diphosphohydrolase,核苷酸双磷酸酶)在哺乳动物中分布于细胞膜,可以水解细胞外ATP和其他核苷酸,从而调控胞外核苷酸代谢及信号应答.根据水稻NTPD基因序列设计引物,在不同胁迫条件样品中,通过PCR扩增水稻NTPD基因,结果表明水稻NTPD基因表达水平在盐胁迫样品中升高.为进一步分析水稻NTPD基因的功能,构建了该基因的过量表达、RNA干涉载体,通过根癌农杆菌介导转入水稻品种日本晴并获得阳性植株.半定量RT-PCR分析达到过量表达和干涉目的.在盐胁迫条件下,T0代过表达转基因植株表现出一定程度的抗胁迫能力,RNA干涉转基因植株的生长则受到抑制.

In mammalian,nucleoside triphosphate-diphosphohydrolases （NTPD） is anchored in the plasma to hydrolyze ectonucleoside ATP and other nucleosides. Thus,NTPD can control the concentration of extracellular nucleotides to regulate nucleotides metabolism,as well as signal response. In the present study,according to the sequence of OsNTPD,the primers were designed and the full-length sequence of OsNTPD was amplified by PCR in Nipponbare with different treatments. It was shown that the expression levels of OsNTPD increased under salt retreatment. To identify the function of OsNTPD, the over-expressing and RNA-interference vectors of OsNTPD were constructed and introduced into rice （Oryza sativa L. cv. Nipponbare） by Agrobacterium-mediated transformation. The semi-quantitative RT-PCR revealed an increase of OsNTPD expression levels in the over-expressing transgenic plants and a significant reduction in the RNAi transgenic plants. Under salt stress, TO over-expressing transgenic plants showed more or less resistance, whereas the growth ofRNAi transgenic rice plants was suppressed. Fig 7, Tab 3, Ref 20