Function of calcium‐dependent protein kinase CPK28 of Arabidopsis thaliana in plant stem elongation and vascular development
- 15 January 2013
- journal article
- Published by Wiley in The Plant Journal
- Vol. 73 (6), 883-896
- https://doi.org/10.1111/tpj.12090
Abstract
After a period of vegetative growth, plants undergo a developmental switch to the reproductive phase, inducing the transition to bolting, elongation of the inflorescence and flowering. We have identified calcium-dependent protein kinase CPK28 from Arabidopsis thaliana as a regulatory component that controls stem elongation and vascular development. In two independent mutant alleles of cpk28, a reduction of stem elongation, accompanied by shorter leaf petioles and enhanced anthocyanin levels, is observed upon the transition to the generative phase. Anatomical analysis revealed an altered vascular pattern characterised by fewer xylem tracheary elements but at the same time increased lignification and secondary growth. Coincident with these morphological changes, cpk28 mutants showed altered expression of NAC transcriptional regulators NST1 and NST3 as well as of GA3ox1, a key regulator of gibberellic acid homeostasis. In vitro protein kinase activity of CPK28 is strictly calcium-dependent. Furthermore, CPK28 is phosphorylated in vivo at several sites. Site-specific amino acid substitutions at these phosphorylation sites resulted in reduced in vitro activity. However, when introduced into a cpk28 mutant background, wild-type and phosphorylation site variants, but not kinase-inactive variants of CPK28 complemented the morphological and developmental defects. Our data identify CPK28 as a developmentally controlled regulator for coordinated stem elongation and secondary growth.Keywords
This publication has 65 references indexed in Scilit:
- Biochemical regulation of in vivo function of plant calcium-dependent protein kinases (CDPK)Biochimica et Biophysica Acta (BBA) - Molecular Cell Research, 2013
- GABI-Kat SimpleSearch: new features of the Arabidopsis thaliana T-DNA mutant databaseNucleic Acids Research, 2011
- Calcium-Dependent Protein Kinase CPK21 Functions in Abiotic Stress Response in Arabidopsis thalianaMolecular Plant, 2011
- Guard cell anion channel SLAC1 is regulated by CDPK protein kinases with distinct Ca 2+ affinitiesProceedings of the National Academy of Sciences of the United States of America, 2010
- Tobacco Calcium-dependent Protein Kinases Are Differentially Phosphorylated in Vivo as Part of a Kinase Cascade That Regulates Stress ResponseOnline Journal of Public Health Informatics, 2010
- Differential innate immune signalling via Ca2+ sensor protein kinasesNature, 2010
- Activity of guard cell anion channel SLAC1 is controlled by drought-stress signaling kinase-phosphatase pairProceedings of the National Academy of Sciences of the United States of America, 2009
- GA4 Is the Active Gibberellin in the Regulation ofLEAFYTranscription andArabidopsisFloral InitiationTHE PLANT CELL ONLINE, 2006
- The single-step method of RNA isolation by acid guanidinium thiocyanate–phenol–chloroform extraction: twenty-something years onNature Protocols, 2006
- Calcium-dependent protein kinases play an essential role in a plant defence responseThe EMBO Journal, 2001