title: Mutational analysis of Arabidopsis PP2CA2 involved in abscisic acid signal transduction.
abstract: The homozygous T-DNA mutant of the PP2CA2 gene in Arabidopsis thaliana was identified at DNA and RNA levels. The semi-quantitative RT-PCR analysis showed expression of PP2CA2 was induced by NaCl and ABA. When grown in presence of increasing concentration of exogenous ABA the pp2ca2 mutant showed a significant loss of ABA sensitivity in terms of seed germination, efficiency of post-germination growth and root growth. In presence of all ABA and NaCl concentrations tested the germination percentage of wild-type seeds was lower than that of mutant ppca2 seeds. Furthermore, in the presence of exogenous ABA, the pp2ca2 seeds showed higher germination percentages than wild-type at different stages of development and the pp2ca2 seedlings showed a reduced inhibition of root growth compared with wild-type plants. The above results indicated that the pp2ca2 was an ABA-hyposensitive mutant.
authors: Institute of Life Science and Biotechnology, State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, 410082, Changsha, People's Republic of China. xinhong@hnu.cn
authors: Xin-Hong
authors: XH
authors: Guo
authors: Ke-Qin
authors: KQ
authors: Deng
authors: Jie
authors: J
authors: Wang
authors: Da-Shi
authors: DS
authors: Yu
authors: Qiong
authors: Q
authors: Zhao
authors: Xuan-Ming
authors: XM
authors: Liu
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism* / Q000494:pharmacology; D000064:Acclimatization / Q000235:genetics; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development; D029681:Arabidopsis Proteins / Q000235:genetics; D004252:DNA Mutational Analysis; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D018525:Germination / Q000187:drug effects / Q000235:genetics; D007527:Isoenzymes / Q000235:genetics; D008969:Molecular Sequence Data; D050505:Mutant Proteins / Q000235:genetics; D010749:Phosphoprotein Phosphatases / Q000235:genetics*; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction / Q000187:drug effects / Q000235:genetics; D012965:Sodium Chloride / Q000494:pharmacology; D013312:Stress, Physiological / Q000187:drug effects / Q000235:genetics
chemical_list: D029681:Arabidopsis Proteins; D007527:Isoenzymes; D050505:Mutant Proteins; D012965:Sodium Chloride; D000040:Abscisic Acid; D010749:Phosphoprotein Phosphatases