title: YdiV: a dual function protein that targets FlhDC for ClpXP-dependent degradation by promoting release of DNA-bound FlhDC complex.
abstract: YdiV is an EAL-like protein that acts as a post-transcriptional, negative regulator of the flagellar master transcriptional activator complex, FlhD(4)C(2), in Salmonella enterica to couple flagellar gene expression to nutrient availability. Mutants defective in ClpXP protease no longer exhibit YdiV-dependent inhibition of FlhD(4)C(2)-dependent transcription under moderate YdiV expression conditions. ClpXP protease degrades FlhD(4)C(2), and this degradation is accelerated in the presence of YdiV. YdiV complexed with both free and DNA-bound FlhD(4)C(2); and stripped FlhD(4)C(2) from DNA. A L22H substitution in FlhD was isolated as insensitive to YdiV inhibition. The FlhD L22H substitution prevented the interaction of YdiV with free FlhD(4)C(2) and the ability of YdiV to release FlhD(4)C(2) bound to DNA. These results demonstrate that YdiV prevents FlhD(4)C(2)-dependent flagellar gene transcription and acts as a putative adaptor to target FlhD(4)C(2) for ClpXP-dependent proteolysis. Our results suggest that YdiV is an EAL-like protein that has evolved from a dicyclic-GMP phosphodiesterase into a dual-function regulatory protein that connects flagellar gene expression to nutrient starvation.
authors.affiliation: Department of Microbiology and Molecular Genetics, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, 260-8675 Japan.
authors.forename: Akiko
authors.initials: A
authors.lastname: Takaya
authors.forename: Marc
authors.initials: M
authors.lastname: Erhardt
authors.forename: Kiyonobu
authors.initials: K
authors.lastname: Karata
authors.forename: Kelly
authors.initials: K
authors.lastname: Winterberg
authors.forename: Tomoko
authors.initials: T
authors.lastname: Yamamoto
authors.forename: Kelly T
authors.initials: KT
authors.lastname: Hughes
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D001665:Binding Sites; D004269:DNA, Bacterial / Q000235:genetics / Q000378:metabolism; D049071:Endopeptidase Clp / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D005407:Flagella / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D059748:Proteolysis; D012486:Salmonella typhimurium / Q000737:chemistry / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D015534:Trans-Activators / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D015534:Trans-Activators; D049071:Endopeptidase Clp