Independent and interchangeable multimerization domains of the AbrB, Abh, and SpoVT global regulatory proteins.
The global regulators AbrB, Abh, and SpoVT are paralogous proteins showing their most extensive sequence homologies in the DNA-binding amino-terminal regions (about 50 residues). The carboxyl-terminal portion of AbrB has been hypothesized to be a multimerization domain with little if any role in DNA-binding recognition or specificity. To investigate the multimerization potentials of the carboxyl-terminal portions of AbrB, Abh, and SpoVT we utilized an in vivo multimerization assay system based upon fusion of the domains to the DNA binding domain of the lambda cI repressor protein. The results indicate that the N and C domains of all three paralogues are independent dimerization modules and that the intact Abh and SpoVT proteins are most probably tetramers. Chimeric proteins consisting of the AbrB N-terminal DNA-binding domain fused to the C domain of either Abh or SpoVT are indistinguishable from wild-type AbrB in their ability to regulate an AbrB target promoter in vivo.
Yao
Fude
F
Dental School, Department of Biomedical Sciences, University of Maryland, 666 W. Baltimore Street, Baltimore, MD 21201, USA.
Strauch
Mark A
MA
D001426:Bacterial Proteins; D001665:Binding Sites / Q000235:genetics; D004268:DNA-Binding Proteins / Q000502:physiology*; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology*; D011487:Protein Conformation; D012097:Repressor Proteins / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D013329:Structure-Activity Relationship; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D014158:Transcription, Genetic / Q000235:genetics
C060762:AbrB protein, Bacillus subtilis; D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D012097:Repressor Proteins; D014157:Transcription Factors