title: CYCLIN-DEPENDENT KINASE G2 regulates salinity stress response and salt mediated flowering in Arabidopsis thaliana.
abstract: Cyclin-dependent protein kinases are involved in many crucial cellular processes and aspects of plant growth and development, but their precise roles in abiotic stress responses are largely unknown. Here, Arabidopsis thaliana CYCLIN-DEPENDENT KINASE G2 (CDKG2) was shown to act as a negative regulator of the salinity stress response, as well as being involved in the control of flowering time. GUS expression experiments based on a pCDKG2::GUS transgene suggested that CDKG2 was expressed throughout plant development, with especially high expression levels recorded in the seed and in the flower. The loss-of-function of CDKG2 led to an increased tolerance of salinity stress and the up-regulation of the known stress-responsive genes SOS1, SOS2, SOS3, NHX3, RD29B, ABI2, ABI3, MYB15 and P5CS1. Flowering was accelerated in the cdkg2 mutants via the repression of FLC and the consequent up-regulation of FT, SOC1, AP1 and LFY. Transgenic lines constitutively expressing CDKG2 showed greater sensitivity to salinity stress and were delayed in flowering. Furthermore, the CDKG2 genotype affected the response of flowering time to salinity stress. Our data connect CDKG2 to undescribed functions related to salt stress tolerance and flowering time through the regulation of specific target genes.
authors.affiliation: Key Laboratory of Plant Cell Engineering and Germplasm Innovation, Ministry of Education, School of Life Science, Shandong University, Jinan, 250100, China.
authors.forename: Xiaoyan
authors.initials: X
authors.lastname: Ma
authors.forename: Zhu
authors.initials: Z
authors.lastname: Qiao
authors.forename: Donghua
authors.initials: D
authors.lastname: Chen
authors.forename: Weiguo
authors.initials: W
authors.lastname: Yang
authors.forename: Ruijia
authors.initials: R
authors.lastname: Zhou
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.forename: Mei
authors.initials: M
authors.lastname: Wang
mesh_terms: D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics / Q000502:physiology*; D018844:Cyclin-Dependent Kinases / Q000502:physiology*; D035264:Flowers; D017343:Genes, Plant; D030821:Plants, Genetically Modified; D020133:Reverse Transcriptase Polymerase Chain Reaction; D054712:Salinity; D013312:Stress, Physiological; D013347:Subcellular Fractions / Q000201:enzymology; D014158:Transcription, Genetic
chemical_list: D018844:Cyclin-Dependent Kinases