Analysis of the downstream region of nodD3 P1 promoter by deletion and complementation tests in Sinorhizobium meliloti  

作　　者：陈迪 刘彦杰 朱家璧 沈善炯 俞冠翘 

机构地区：[1]Laboratory of Molecular Genetics, Shanghai Institute of Plant Physiology and Ecology,Shanghai Institutes of Bio-logical Science,Chinese Academy of Sciences,Shanghai 200032, China

出　　处：《Science China(Life Sciences)》2003年第2期165-173,共9页中国科学（生命科学英文版）

基　　金：This work was supported by the National High Technology 863 Programs of China; the 973 Project of the Ministry of Science and Technology (Grant No. 001CB108901) and the fund of the Shanghai Institutes of Biological Sciences.

摘　　要：In Sinorhizobium meliloti, the nodD3 gene is transcriptionally controlled by two promot-ers, P1 and P2. Under P1, there is a 660 bp sequence including a small open reading frame, ORF2, followed by the nodD3 coding region. Genetic analysis using the different deletions on the 3′ends of P1 downstream sequence showed that the downstream sequence +1—+125nt is es-sential for P1 expression. Complementation, mutations and nodulation tests demonstrated that the ORF2 auto-represses P1 expression, while the P1 downstream sequence +1—+125nt counteracts it.In Sinorhizobium meliloti, the nodD3 gene is transcriptionally controlled by two promot-ers, P1 and P2. Under P1, there is a 660 bp sequence including a small open reading frame, ORF2, followed by the nodD3 coding region. Genetic analysis using the different deletions on the 3′ends of P1 downstream sequence showed that the downstream sequence +1—+125nt is es-sential for P1 expression. Complementation, mutations and nodulation tests demonstrated that the ORF2 auto-represses P1 expression, while the P1 downstream sequence +1—+125nt counteracts it.

关 键 词：SINORHIZOBIUM meliloti  nodD3 gene  DOWNSTREAM sequence  autoregulation. 

分 类 号：Q343.1[生物学—遗传学]