NodV and NodW, a second flavonoid recognition system regulating nod gene expression in Bradyrhizobium japonicum.
AUTOR(ES)
Loh, J
RESUMO
In Bradyrhizobium japonicum, members of two global regulatory families, a LysR-type regulator, NodD1, and a two-component regulatory system, NodVW, positively regulate nod gene expression in response to plant-produced isoflavone signals. By analogy to other two-component systems, NodV and NodW are thought to activate transcription via a series of phosphorylation steps. These include the phosphorylation of NodV in response to the plant signal and the subsequent activation of NodW via the transfer of the phosphoryl group to an aspartate residue in the receiver domain of NodW. In this study, we demonstrated that NodW can be phosphorylated in vitro by both acetyl phosphate and its cognate kinase, NodV. In addition, in vivo experiments indicate that phosphorylation is induced by genistein, a known isoflavone nod gene inducer in B. japonicum. By using site-directed mutagenesis, a NodWD70N mutant in which the aspartate residue at the proposed phosphorylation site was converted to an asparagine residue was generated. This mutant was not phosphorylated in either in vitro or in vivo assays. Comparisons of the biological activity of both the wild-type and mutant proteins indicate that phosphorylation of NodW is essential for the ability of NodW to activate nod gene expression.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=179067Documentos Relacionados
- Proposed regulatory pathway encoded by the nodV and nodW genes, determinants of host specificity in Bradyrhizobium japonicum.
- Expressão dos genes nodC, nodW e nopP em Bradyrhizobium japonicum estirpe CPAC 15 avaliada por RT-qPCR.
- Expressão dos genes nodC, nodW e nopP em Bradyrhizobium japonicum estirpe CPAC 15 avaliada por RT-qPCR
- Strain-Specific Inhibition of nod Gene Induction in Bradyrhizobium japonicum by Flavonoid Compounds
- Avaliação da expressão dos genes nodC, nodW e nopP na estirpe CPAC 15 (=SEMIA 5079) de Bradyrhizobium japonicum pela técnica de RT-qPCR