Rck2, a member of the calmodulin-protein kinase family, links protein synthesis to high osmolarity MAP kinase signaling in budding yeast

Author(s)
Markus Teige, Elisabeth Scheikl, Vladimir Reiser, Gustav Ammerer
Abstract

Rck2, a yeast Ser/Thr protein kinase homologous to mammalian calmodulin kinases, requires phosphorylation for activation. We provide evidence that in budding yeast, this step can be executed by the osmostress-activated mitogen-activated protein kinase Hog1. Rck2 phosphorylation was transiently increased during osmostress or in mutants with a hyperactive high osmolarity glycerol (HOG) pathway. This modification depended on catalytically active Hog1 kinase and two putative mitogen-activated protein kinase phosphorylation sites in Rck2. Immunokinase assays showed that Hog1 can directly phosphorylate Rck2 to stimulate its enzymatic activity toward translation elongation factor 2. We demonstrate that Hog1 and Rck2 are necessary for attenuation of protein synthesis in response to osmotic challenge and show that modification of elongation factor 2 induced by osmostress depends on Rck2 and Hog1 in vivo. Therefore, we propose that the transient down-regulation of protein synthesis after osmotic shock is a response not to damage but to an extracellular signal mediated by Hog1 and Rck2.

Organisation(s)
Department of Biochemistry and Cell Biology
External organisation(s)
Harvard University, Universität Wien
Journal
Proceedings of the National Academy of Sciences of the United States of America (PNAS)
Volume
98
Pages
5625-5630
No. of pages
6
ISSN
0027-8424
DOI
https://doi.org/10.1073/pnas.091610798
Publication date
2001
Peer reviewed
Yes
Austrian Fields of Science 2012
1060 Biology
Portal url
https://ucris.univie.ac.at/portal/en/publications/rck2-a-member-of-the-calmodulinprotein-kinase-family-links-protein-synthesis-to-high-osmolarity-map-kinase-signaling-in-budding-yeast(ce491be7-3602-4402-84b1-e2cf52b337ac).html