The alkaline tolerance in Arabidopsis requires stabilizing microfilament partially through inactivation of PKS5 kinase  

作　　者：Juntao Liu Yan Guo 

机构地区：[1]State Key Laboratory of Plant Physiology and Biochemistry, College of Biological Sciences, China Agricultural University, Beijing 100094, China [2]National Institute of Biological Sciences, Beijing, No. 7 Science Park Road, Zhongguancun Life Science Park, Beijing 102206, China

出　　处：《Journal of Genetics and Genomics》2011年第7期307-313,共7页遗传学报（英文版）

基　　金：supported by the grant of China National Funds for Distinguished Young Scientists(No.31025003)to Y.Guo

摘　　要：High soil pH is harmful to plant growth and development. The organization and dynamics of microfilament （MF） cytoskeleton play important roles in the plant anti-alkaline process. In the previous study, we determined that alkaline stress induces a signal that triggers MF dynamicsdependent root growth. In this study we identified that PKS5 kinase involves in this regulatory process to facilitate the signal to reach the downstream target ME Under pH 8.3 treatment, the depolymerization of MF was faster in pks5-4 （PKS5 kinase constitutively activated） than that in wild-type plants. The inhibition of wild-type, pks5-1, and pks5-4 root growth by pH 8.3 was correlated to their MF depolymerization rate. When the plants were treated with phalloidin to stabilize MF, the high pH sensitive phenotype of pks5-4 can be partially rescued. When the plants were treated with a kinase inhibitor Staurosporine, the MF depolymerization rate in pks5-4 was similar as that in wild-type under pH 8.3 treatment and the sensitivity of root growth was also rescued. However, when the plants were treated with LaC13, a calcium channel blocker, the root growth sensitivity ofpks5-4 under pH 8.3 was rescued but MF depolymerization was even faster than that of plants without LaC13 treatment. These results suggest that the PKS5 involves in external high pH signal mediated MF depolymerization, and that may be independent of calcium signal.High soil pH is harmful to plant growth and development. The organization and dynamics of microfilament （MF） cytoskeleton play important roles in the plant anti-alkaline process. In the previous study, we determined that alkaline stress induces a signal that triggers MF dynamicsdependent root growth. In this study we identified that PKS5 kinase involves in this regulatory process to facilitate the signal to reach the downstream target ME Under pH 8.3 treatment, the depolymerization of MF was faster in pks5-4 （PKS5 kinase constitutively activated） than that in wild-type plants. The inhibition of wild-type, pks5-1, and pks5-4 root growth by pH 8.3 was correlated to their MF depolymerization rate. When the plants were treated with phalloidin to stabilize MF, the high pH sensitive phenotype of pks5-4 can be partially rescued. When the plants were treated with a kinase inhibitor Staurosporine, the MF depolymerization rate in pks5-4 was similar as that in wild-type under pH 8.3 treatment and the sensitivity of root growth was also rescued. However, when the plants were treated with LaC13, a calcium channel blocker, the root growth sensitivity ofpks5-4 under pH 8.3 was rescued but MF depolymerization was even faster than that of plants without LaC13 treatment. These results suggest that the PKS5 involves in external high pH signal mediated MF depolymerization, and that may be independent of calcium signal.

关 键 词：ARABIDOPSIS Alkaline stress MICROFILAMENT Kinase activity 

分 类 号：Q245[生物学—细胞生物学] TS802.6[轻工技术与工程]