水稻OsMED7基因的克隆及表达分析

Cloning and Expression of OsMED7 from Rice

转录中介体复合物(Mediator com-plex)是一个由多亚基组成的RNA聚合酶II重要辅助因子,参与真核生物基因的转录调控。通过RT-PCR方法从水稻中克隆了拟南芥MED7的同源基因,命名为OsMED7,该基因的开放阅读框全长为531bp,编码一个含176个氨基酸的蛋白,含有一个MED7保守结构域。用水杨酸处理水稻幼苗后OsMED7基因的表达受到抑制,而茉莉酸的处理对OsMED7基因的表达没有影响,水稻接种白叶枯病菌24h后OsMED7基因的表达开始下降。结果表明,OsMED7亚基通过SA介导的信号转导途径参与水稻对白叶枯病菌的应答。

Mediator complex is a supplementary factor of RNA polymerase II and involved in eukaryotic transcrip- tional regulation. According to the sequence of MED7 in Arabidopsis, the homolog was isolated by RT-PCR from Oryza sativa, and designated OsMED7. The length of the open reading frame of OsMED7is 531bp,which coded a protein including 176 amino acids. Biological information analysis showed that OsMED7 includes a MED7 conserved domain. The expression of OsMED7was suppressed by Salylic acid（SA） and Xanthomonas oryzae pv. Oryzae（Xoo） that cause rice bacterial blight, but no change by Jasmonic acid （JA）. These data implied that OsMED7 may be in- volved in the response of rice to Xoo by SA-mediated signaling pathway.