脱落酸对水稻根系生长素合成与运输的调控

Research of Abscisic Acid Modulated Auxin Biosynthesis and Transport in Rice Root

摘要: 利用一系列不同浓度的脱落酸（ABA）处理水稻幼苗根系，观察水稻初生根根长、冠根数目、侧根数目及长度、DR5：：GUS转基因材料GUS活性、生长素的合成及运输相关基因表达水平等变化.结果表明，ABA可以抑制水稻初生根的伸长、冠根和侧根的发生和伸长，并且抑制效应呈现剂量效应.DR5：：GUS活性在整个根系中随ABA处理浓度升高而减弱，但根尖部位的DR5：：GUS活性经过ABA处理后表现增强；生长素合成相关基因YUCCA2、YUCCA4、YUCCA7，生长素运输载体基因AUX3、AUX5、PiN1b、PiN2、PiN5a、PiN9、PiN10a均显著下降表达.

Abstract: The rice seedlings were treated by difference concentration of ABA (abscisic acid). The root phenotype, DR5::GUS expression pattern, the changes of auxin biosynthesis and transport genes expression in were studied. The results demonstrated that primary root elongation, crown root initiation, and lateral root initiation and elongation was inhibited in ABA treated seedling. Besides, GUS activity was also reduced in the ABA treated DR5::GUS transgenic plants. On the contrary, GUS activity in root tip increased with ABA treatment. Furthermore, Both auxin biosynthesis genes YUCCA2, YUCCA4, YUCCA7, and auxin transport genes AUX3, AUX5, PiN1b, PiN2, PiN5a, PiN9, PiN10a were down-regulated in ABA treated rice root.