Various abiotic stresses rapidly activate Arabidopsis MAP kinases ATMPK4 and ATMPK6.
Mitogen-activated protein kinase (MAP kinase, MAPK) cascades play pivotal roles in signal transduction of extracellular stimuli, such as environmental stresses and growth regulators, in various organisms. Arabidopsis thaliana MAP kinases constitute a gene family, but stimulatory signals for each MAP kinase have not been elucidated. Here we show that environmental stresses such as low temperature, low humidity, hyper-osmolarity, touch and wounding induce rapid and transient activation of the Arabidopsis MAP kinases ATMPK4 and ATMPK6. Activation of ATMPK4 and ATMPK6 was associated with tyrosine phosphorylation but not with the amounts of mRNA or protein. Kinetics during activation differ between these two MAP kinases. These results suggest that ATMPK4 and ATMPK6 are involved in distinct signal transduction pathways responding to these environmental stresses.
Ichimura
K
K
Laboratory of Plant Molecular Biology, RIKEN Tsukuba Institute, 3-1-1 Koyadai, Tsukuba, Ibaraki 305-0074, Japan.
Mizoguchi
T
T
Yoshida
R
R
Yuasa
T
T
Shinozaki
K
K
D000040:Abscisic Acid / Q000494:pharmacology; D000911:Antibodies, Monoclonal / Q000276:immunology; D000918:Antibody Specificity; D017360:Arabidopsis / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D004789:Enzyme Activation / Q000187:drug effects; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D006358:Hot Temperature; D015151:Immunoblotting; D007527:Isoenzymes / Q000276:immunology / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000235:genetics / Q000276:immunology / Q000378:metabolism*; D009997:Osmotic Pressure; D010766:Phosphorylation; D011233:Precipitin Tests; D013314:Stress, Mechanical; D013696:Temperature; D014443:Tyrosine / Q000378:metabolism; D014867:Water / Q000494:pharmacology
D000911:Antibodies, Monoclonal; D007527:Isoenzymes; D014867:Water; D014443:Tyrosine; D000040:Abscisic Acid; D020928:Mitogen-Activated Protein Kinases