title: Phosphorylation of Bacillus subtilis gene regulator AbrB modulates its DNA-binding properties.
abstract: AbrB is a global gene regulator involved in transition phase phenomena in Bacillus subtilis. It participates in a complex regulatory network governing the expression of stationary-phase functions. AbrB was previously found to be phosphorylated on serine 86 located close to its C-terminal oligomerization domain. Here we report that AbrB can be phosphorylated by three B. subtilis serine/threonine kinases expressed during the transition and stationary phase: PrkC, PrkD and YabT. Our in vitro findings suggest that AbrB phosphorylation impedes its DNA binding and abolishes binding cooperativity. In vivo we established that a phospho-mimetic mutation abrB S86D leads to a significant loss of AbrB control over several key target functions: exoprotease production, competence development and sporulation. A wider transcriptome analysis of abrB S86D and S86A mutant strains revealed deregulation of a large number of target genes. We therefore propose that AbrB phosphorylation serves as an additional input for fine-tuning the activity of this ambiactive gene regulator.
authors.affiliation: INRA, UMR-1319 Micalis, F-78350, Jouy-en-Josas, France.
authors.forename: Ahasanul
authors.initials: A
authors.lastname: Kobir
authors.forename: Sandrine
authors.initials: S
authors.lastname: Poncet
authors.forename: Vladimir
authors.initials: V
authors.lastname: Bidnenko
authors.forename: Olivier
authors.initials: O
authors.lastname: Delumeau
authors.forename: Carsten
authors.initials: C
authors.lastname: Jers
authors.forename: Samira
authors.initials: S
authors.lastname: Zouhir
authors.forename: Rosa
authors.initials: R
authors.lastname: Grenha
authors.forename: Sylvie
authors.initials: S
authors.lastname: Nessler
authors.forename: Phillipe
authors.initials: P
authors.lastname: Noirot
authors.forename: Ivan
authors.initials: I
authors.lastname: Mijakovic
mesh_terms: D001412:Bacillus subtilis / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D010766:Phosphorylation; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D014157:Transcription Factors