关键词: 桃, 拟南芥, CYP707A, ABA, 过表达, 功能分析

Abstract:

We used eight-year-old‘Zhongyoutao 4’nectarine as the material and then treated dormant peach branches with hormone. The results showed that ABA delayed bud germination，GA promoted germination and precocious flowering，ABA and GA had the adverse effect on the germination of peach buds. We obtained at least 3 homozygous lines with overexpression of ABA 8’-hydroxylase gene which were key enzyme in ABA catabolism in peach such as PpeCYP707A1，PpeCYP707A2，PpeCYP707A3 in Arabidopsis thaliana by transgenic technique. The results of RT-PCR showed that the expression of target gene in overexpression lines reached 23.86 times，7.37 times and 3.23 times，respectively. The Arabidopsis of overexpression lines showed slow growth，delayed bolting even flowering，which PPECYP707A1 slowest growth and flowering the latest. Relative conductivity and active oxygen analysis showed that seed germination and seedling growth of transgenic Arabidopsis were not sensitive to ABA and the damage degree was lower compared to wild type. Low temperature（10 ℃）treatment results showed that the relative growth rate of transgenic Arabidopsis with overexpressing PpeCYP707As was higher than that of wild type. It is speculated that the overexpression of CYP707As gene may positively regulate the growth and development of Arabidopsis under low temperature condition.

Key words: peach, Arabidopsis thaliana, CYP707A, ABA, overexpression, functional analysis