A novel kinase cascade triggered by stress and heat shock that stimulates MAPKAP kinase-2 and phosphorylation of the small heat shock proteins.
MAPK-activated protein kinase-2 (MAPKAP kinase-2) is activated in vitro by the p42 and p44 isoforms of MAPK (p42/p44MAPK). In several cell lines, however, MAPKAP kinase-2 is activated by sodium arsenite, heat shock, or osmotic stress and not by agonists that activate p42/p44MAPK. We have identified a MAPK-like enzyme that acts as a MAPKAP kinase-2 reactivating kinase (RK). RK is recognized by an antiserum raised against a Xenopus MAPK (Mpk2), which is most similar to HOG1 from S. cerevisiae. We also identified a RK kinase (RKK) on the basis of its ability to activate either RK or a GST-Mpk2 fusion protein. The RKK, RK, and MAPKAP kinase-2 constitute a new stress-activated signal transduction pathway in vertebrates that is distinct from the classical MAPK cascade.
Rouse
J
J
Department of Biochemistry, University of Dundee, Scotland.
Cohen
P
P
Trigon
S
S
Morange
M
M
Alonso-Llamazares
A
A
Zamanillo
D
D
Hunt
T
T
Nebreda
A R
AR
D000595:Amino Acid Sequence; D000818:Animals; D018053:Arsenites / Q000494:pharmacology; D001483:Base Sequence; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000235:genetics / Q000378:metabolism; D055551:HSP27 Heat-Shock Proteins; D006360:Heat-Shock Proteins / Q000378:metabolism*; D006358:Hot Temperature / Q000009:adverse effects; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D020928:Mitogen-Activated Protein Kinases; D018832:Molecular Chaperones; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins / Q000378:metabolism; D010766:Phosphorylation; D011494:Protein Kinases; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D051381:Rats; D012441:Saccharomyces cerevisiae / Q000235:genetics; D029701:Saccharomyces cerevisiae Proteins; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction; D014981:Xenopus / Q000235:genetics; D029867:Xenopus Proteins; D000099190:MAP-Kinase-Activated Kinase 2
D018053:Arsenites; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D055551:HSP27 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D047908:Intracellular Signaling Peptides and Proteins; D020928:Mitogen-Activated Protein Kinases; D018832:Molecular Chaperones; D009363:Neoplasm Proteins; D011494:Protein Kinases; D017346:Protein Serine-Threonine Kinases; D029701:Saccharomyces cerevisiae Proteins; D029867:Xenopus Proteins; D000099190:MAP-Kinase-Activated Kinase 2; C057725:HSPB1 protein, human; C486114:Hspb1 protein, rat; C089646:Mpk2 protein, Xenopus; C088589:HOG1 protein, S cerevisiae; C490332:mapk14a protein, Xenopus; C015001:arsenite