关键词: 苹果, MdPP2C-Like, 蛋白磷酸酶, 过表达, ABA

Abstract:

Protein phosphatase gene MdPP2C-Like（MDP0000126636），an important factor that was involved in ABA signal pathway，was cloned from apple（Malus × domestica Borkh.）. Gene structure analysis showed that MdPP2C-Like gene contained 5 exons and 4 introns，and it was located on the eighth chromosome of apple genome. After amplification，a 1 035 bp open reading frame（ORF）was obtained. MdPP2C-Like gene encoded a protein of 344 amino acids with a calculated mass of 37.84 kD and an isoelectric point（pI）of 5.72. MdPP2C-Like protein sequence comprised a conserved phosphatase 2C （PP2C）domain，just as group A AtPP2Cs. The phylogenetic tree of the construction indicated that MdPP2C-Like and At4G32950 were located in the same evolutionary branch and had high homology. MdPP2C-Like gene mainly localized in the nucleus，with a few in cytoplasm. The expression level of MdPP2C-Like was different in all apple tissues，with the highest level in roots. Moreover，overexpression of MdPP2C-Like gene in apple callus and Arabidopsis plants reduced the sensitivity to ABA. Taken together，these findings showed that MdPP2C-Like played an important role in response to ABA signaling.

Key words: apple, MdPP2C-Like, protein phosphatase, overexpression, ABA