MAP18参与ABA调控拟南芥花粉生长的研究

Functions of MAP18 in the Modulation of Pollen Growth in Arabidopsis thaliana by ABA

[目的]探讨微管结合蛋白MAP18在ABA调控拟南芥花粉生长中的作用,为进一步深入研究植物的极性发育模式提供线索。[方法]以拟南芥野生型(生态型Columbia,Col-0)及相关突变体花粉为试验材料,进行遗传学和药理学分析,研究花粉萌发和花粉管生长的调控因子。[结果]内源和外源ABA均显著抑制拟南芥花粉的萌发,但内源ABA对萌发的花粉管有促进伸长的作用。遗传学证据表明,微管结合蛋白MAP18过表达植株的花粉对ABA表现超敏感,而RNAi沉默株的花粉对ABA则表现出脱敏感现象,显示MAP18蛋白参与了ABA对花粉萌发及花粉管生长的调控过程。[结论]该试验结果为研究花粉萌发与花粉管生长调控模式提供了线索。

[ Objective] To discuss the functions of MAP18 in the modulation of pollen growth in Arabidospsis thaliana by ABA, so as to pro- vide references for the in-depth study of the polarity development pattern in plants. [ Method ] With the wild type Col-0, ecotype Columbia and mutants of Arabidopsis thaliana pollens as test materials, a genetic and pharmacological analysis was carried out to study the factors modulating the pollen germination and growth. [ Result] Both the endogenous and exogenous ABA could significantly inhibit the germination of pollen, while only the endogenous ABA could promote the elongation of pollen tube. And genetics analysis showed that pollen in plants overexpressed with MAP18 was hypersensitive to exogenous ABA, while that of the plants in which MAP18 was downregulated by RNA interference （RNAi） was not sensitive to ABA. These results showed that MAP18 was involved in modulation of ABA on pollen growth in A. thaliana. [ Conclu- sion ] This study provides some clues on the regulation model of pollen germination and pollen tube growth.