Opposing pairs of serine protein kinases and phosphatases transmit signals of environmental stress to activate a bacterial transcription factor.
Year: 1996
Type: preprint
Abstract: The general stress response of the bacterium Bacillus subtilis is governed by a signal transduction network that regulates activity of the sigma(B) transcription factor. We show that this network comprises two partner-switching modules, RsbX-RsbS-RsbT and RsbU-RsbV-RsbW, which contribute to regulating sigma(B). Each module consists of a phosphatase (X or U), an antagonist protein (S or V), and a switch protein/kinase (T or W). In the downstream module, the W anti-sigma factor is the primary regulator of sigma(B) activity. If the V antagonist is phosphorylated, the W switch protein binds and inhibits sigma(B). If V is unphosphorylated, it complexes W, freeing sigma(B) to interact with RNA polymerase and promote transcription. The phosphorylation state of V is controlled by opposing kinase (W) and phosphatase (U) activities. The U phosphatase is regulated by the upstream module. The T switch protein directly binds U, stimulating phosphatase activity. The T-U interaction is governed by the phosphorylation state of the S antagonist, controlled by opposing kinase (T) and phosphatase (X) activities. This partner-switching mechanism provides a general regulatory strategy in which linked modules sense and integrate multiple signals by protein-protein interaction.
Source: Genes & Development
Authors: X Yang, C M Kang, M S Brody, C W Price
Institution: University of California, Davis
Language: English
Subfield: Genetics
Domain: Life Sciences
Open Access status: bronze
OpenAlex ID: W2083804547