title: Expression of a kinase-dead form of CPK33 involved in florigen complex formation causes delayed flowering.
abstract: Regulation of flowering time is crucial for reproductive success of plants. FLOWERING LOCUS T (FT) protein is a central component of florigen and forms a ternary complex with 14-3-3 and FD, a basic leucine zipper transcription factor, in the shoot apex and promotes flowering. This complex formation requires phosphorylation of threonine residue at position 282 of FD. A calcium-dependent protein kinase CPK33 is responsible for the phosphorylation. However, possibly due to functional redundancy among calcium-dependent protein kinases, impact of the loss of CPK33 reported in the previous study was rather limited. Here, we report that expression of a kinase-dead form of CPK33 caused a clear delayed-flowering phenotype, supporting for an important role of CPK33 in florigen function through FD phosphorylation.
authors.affiliation: a Division of Integrated Life Science; Graduate School of Biostudies; Kyoto University ; Kyoto , Japan.
authors.forename: Nozomi
authors.initials: N
authors.lastname: Kawamoto
authors.affiliation: a Division of Integrated Life Science; Graduate School of Biostudies; Kyoto University ; Kyoto , Japan.
authors.forename: Motomu
authors.initials: M
authors.lastname: Endo
authors.affiliation: a Division of Integrated Life Science; Graduate School of Biostudies; Kyoto University ; Kyoto , Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Araki
mesh_terms: D017360:Arabidopsis / Q000201:enzymology* / Q000502:physiology*; D029681:Arabidopsis Proteins / Q000378:metabolism*; D060405:Florigen / Q000378:metabolism*; D035264:Flowers / Q000201:enzymology* / Q000502:physiology*; D005799:Genes, Dominant; D011494:Protein Kinases / Q000378:metabolism*; D017871:Calcium-Calmodulin-Dependent Protein Kinases
chemical_list: D029681:Arabidopsis Proteins; D060405:Florigen; D011494:Protein Kinases; C000611601:CPK33 protein, Arabidopsis; D017871:Calcium-Calmodulin-Dependent Protein Kinases
keywords: CDPK; FD; FLOWERING LOCUS T; flowering; phosphorylation