拟南芥中磷脂酶Dγ2的低温信号转导作用途径分析

Signal Transduction Pathway of Arabidopsis Phospholipase Dγ2 in the Low Temperature

磷脂酶D(PLD)的磷脂降解功能和信号转导功能均能影响植物的抗冻性。本研究以PLDγ2基因被敲除的拟南芥突变体及其野生型为材料,进行低温驯化和冻害胁迫处理,随后由这两种植株的表型及其离子渗透率等来分析PLDγ2基因对拟南芥抗冻性。结果发现,经直接冻害处理后,PLDγ2敲除型的抗冻性与野生型基本一致;但经过低温驯化后的冻害处理,PLDγ2敲除型的抗冻性弱于野生型,即表明PLDγ2基因参与了低温信号转导作用。进一步的实验结果表明PLDγ2基因介导脯氨酸调控的可溶性物质调控途径和过氧化物酶(POD)活性调控的抗氧化系统途径;但是与低温信号激素ABA不在同一条信号转导途径。

Both the functions of phospholipid degradation and signal transduction of phospholipase D(PLD) could affect plant freezing tolerance.In this research,we employed a PLDγ2 gene knockout mutant of Arabidopsis thaliana and its wild-type plants as the tested materials by treatment with cold acclimated and freezing stressed in a climate chamber,and then we detected the changes in phenotype and membrane ion leakage of these tested materials in order to clarify freezing tolerance of PLDγ2 gene in Arabidopsis thaliana.The results showed that PLDγ2-KO plants has the same freezing tolerance with its wild-type after freezing stressed,but PLDγ2-KO plants was consistently less resistant to freezing than wild-type after cold-acclimation and freezing stressed.These results indicated that PLDγ2 gene mediated in signal transduction function of low temperature,further experimental results make clear that PLDγ2 gene involved in osmotic adjustment pathway in the process of low temperature signal transduction mainly by regulating proline level and anti-oxidation system regulation which mainly by regulating POD activity,but it was not in the same pathway in which of signal hormone ABA.