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CtsR, the Gram-positive master regulator of protein quality control, feels the heat.

ABSTRACT: Protein quality networks are required for the maintenance of proper protein homeostasis and essential for viability and growth of all living organisms. Hence, regulation and coordination of these networks are critical for survival during stress as well as for virulence of pathogenic species. In low GC, Gram-positive bacteria central protein quality networks are under the control of the global repressor CtsR. Here, we provide evidence that CtsR activity during heat stress is mediated by intrinsic heat sensing through a glycine-rich loop, probably in all Gram-positive species. Moreover, a function for the recently identified arginine kinase McsB is confirmed, however, not for initial inactivation and dissociation of CtsR from the DNA, but for heat-dependent auto-activation of McsB as an adaptor for ClpCP-mediated degradation of CtsR.

SUBMITTER: Elsholz AK

PROVIDER: S-EPMC2982754 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

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CtsR, the Gram-positive master regulator of protein quality control, feels the heat.

Elsholz Alexander K W AK Michalik Stephan S Zühlke Daniela D Hecker Michael M Gerth Ulf U

The EMBO journal 20100917 21

Protein quality networks are required for the maintenance of proper protein homeostasis and essential for viability and growth of all living organisms. Hence, regulation and coordination of these networks are critical for survival during stress as well as for virulence of pathogenic species. In low GC, Gram-positive bacteria central protein quality networks are under the control of the global repressor CtsR. Here, we provide evidence that CtsR activity during heat stress is mediated by intrinsic ...[more]

PMID: 20852588

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CtsR, the Gram-positive master regulator of protein quality control, feels the heat.

Publications

CtsR, the Gram-positive master regulator of protein quality control, feels the heat.

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