title: Analysis of the downstream region of nodD3 P1 promoter by deletion and complementation tests in Sinorhizobium meliloti.
abstract: In Sinorhizobium meliloti, the nodD3 gene is transcriptionally controlled by two promoters, 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 essential 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.
authors.affiliation: Laboratory of Molecular Genetics, Shanghai Institute of Plant Physiology and Ecology, Shanghai Institutes of Biological Science, Chinese Academy of Sciences, 200032, Shanghai, China.
authors.forename: Di
authors.initials: D
authors.lastname: Chen
authors.forename: Yanjie
authors.initials: Y
authors.lastname: Liu
authors.forename: Jiabi
authors.initials: J
authors.lastname: Zhu
authors.forename: Shanjiong
authors.initials: S
authors.lastname: Shen
authors.forename: Guanqiao
authors.initials: G
authors.lastname: Yu