Calcium and protein kinase serve as the common mediators to regulate plant responses to multiple stresses including salt and ABA stimulus. Here we reported a novel protein kinase (CIPK14) that regulated the responses to ABA treatment and salt stress in Arabidopsis. CIPK14 transcripts, capable been checked in roots, stems, leaves and flowers, were highly expressed in flowers and roots. CIPK14 was induced by ABA and salt treatments. The disruption of CIPK14 altered the transcriptional pattern of a gene marker line related to ABA and salt responses, and the results suggested that CIPK14 probably was responsible to the control of the salt and ABA responses. Comparing with wild types, the lines inserted with the T-DNA in which CIPK14 gene expression was knocked out were also more sensitive to ABA and salt stimulus, showing low germination rate and the less root elongation. While, when these conditioned seeds were treated with norflurazon, their germination percentages could recover to a certain extent. We also found that exogenous calcium could have an effect on the transcription of CIPK14 under ABA and salt treatments, and it seemed that calcium ion might work upstream CIPK14 to regulate the plant response to ABA and salt response.
QIN YuZhi1,2, LI Xu1, GUO Ming1, DENG KeQin1, LIN JianZhong1, TANG DongYing1, GUO XinHong1 & LIU XuanMing1 1 College of Life Science and Biotechnology, Bioenergy and Biomaterial Research Center, Hunan University, Changsha 410082, China 2 College of living resources & Environment Science, Jishou University, Jishou 416000, China
Phytochromes are a family of plant photoreceptors that mediate physiological and developmental re- sponses to red and far-red light. According to the affymetrix ATH1 microarray, phytochrome A (phyA) and phytochrome B (phyB) together play a key role in transducing the Rc signals to light-responsive genes. In order to select those red light-responsive genes associated with phyA or phyB, a proteomic approach based on two-dimensional gel electrophoresis (2-DE) was used to compare the protein ex- pression patterns of the phyAphyB double mutant and the wild type of Arabidopsis thaliana (col-4) which grew under constant red light conditions for 7 d. Thirty-two protein spots which exhibited dif- ferences in protein abundance were identified by matrix-assisted laser desorption/ionization-time of flight/time of flight mass spectrometry. The expression of ten genes corresponding to ten protein spots was analyzed by a semiquantitative reverse transcription-polymerase chain reaction. Two of the ten genes were confirmed by quantitative PCR (Q-PCR). The results showed that phytochromes may exert their function by regulating mRNA or protein expressions. Proteomic analysis may provide a novel pathway for identifying phytochrome-dependent genes.
LI XuYANG YueJunLI YanWANG JieXIAO XiaoJuanGUO XinHongTANG DongYingLIU XuanMing
