Tools - Reference - Detail

Reference Detail

Reference
Author Xie K., Chen J., Wang Q., Yang Y.
Title Direct phosphorylation and activation of a mitogen-activated protein kinase by a calcium-dependent protein kinase in rice.
Abstract:
The mitogen-activated protein kinase (MAPK) is a pivotal point of convergence for many signaling pathways in eukaryotes. In the classical MAPK cascade, a signal is transmitted via sequential phosphorylation and activation of MAPK kinase kinase, MAPK kinase (MKK), and MAPK. The activation of MAPK is dependent on dual phosphorylation of a TXY motif by an MKK, which is considered the sole kinase to phosphorylate and activate MAPK. Here, we report a novel regulatory mechanism of MAPK phosphorylation and activation besides the canonical MAPK cascade. A rice (Oryza sativa) calcium-dependent protein kinase (CDPK), CPK18, was identified as an upstream kinase of MAPK (MPK5) in vitro and in vivo. Curiously, CPK18 was shown to phosphorylate and activate MPK5 without affecting the phosphorylation of its TXY motif. Instead, CPK18 was found to predominantly phosphorylate two Thr residues (Thr-14 and Thr-32) that are widely conserved in MAPKs from land plants. Further analyses reveal that the newly identified CPK18-MPK5 pathway represses defense gene expression and negatively regulates rice blast resistance. Our results suggest that land plants have evolved an MKK-independent phosphorylation pathway that directly connects calcium signaling to the MAPK machinery.
Journal Plant Cell
Country unknown
Volume 26(7)
Pages 3077-89
Year 2014
PubMed ID 25035404
PubMed Central ID 4145133
DOI 10.1105/tpc.114.126441
URL -
Relation
Gene CDPK18 MSRMK2
INSD -
Strain Wild Core Collection -
Induced Mutation Lines(NIG Collection) -
Sterile Seed Strain -
Lethal Embryo
Mutantion Strain 		-
Stages in Each Organ
- Muant Lines (Gene) 		-
Cultivated Varieties(NIG Collection) -
Stages in Each Organ -
/rice/oryzabase