摘要
花药开裂是开花植物生殖生长中非常重要的一个环节,花药能否适时开裂直接影响授粉和受精。水稻花药开裂与浆片膨大所导致的颖花开放同步发生。植物激素茉莉酸(JA)是调控花药开裂和颖花开放的重要信号分子。为进一步探讨水稻花药开裂前JA信号的调控,以粳稻中花11为试验材料,对其花药开裂前24 h至0 h茉莉酸水平及其信号途径相关基因表达的动态变化进行了观测与分析。结果发现,花药JA及其活性结合物茉莉脂异亮氨酸(JA-Ile)水平从开裂前2 h起急剧上升。开裂时花药JA和JA-Ile水平较开裂前2 h增加8.3倍和55倍。相应地,JA生物合成基因Os LOX6、Os AOS1、Os AOC和Os OPR7的表达水平在开裂前24 h至0 h有不同程度的上升。然而,JA-Ile合成酶的2个家族基因Os JAR1的表达水平无明显上升,Os JAR2表达迅速下降。花药开裂时JA信号受体基因Os COI1a、Os COI1b和Os COI2的表达水平略有下降,但JA信号途径负调控因子Os JAZ10和Os JAZ11的表达水平大幅上升,分别较开裂前24 h分别升高65和86倍。结果表明,JA水平的上升及其信号途径相关基因的差异性激活与水稻花药开裂过程密切相关。
Anther dehiscence is a critical step for reproduction of flowering plants.Abnormal anther dehiscence will directly result in poor pollination and fertilization.Rice anther dehiscence is synchronized with floret opening which is caused by swelling of lodicules.Phytohormone jasmonate（JA） is an important signaling molecule in regulating anther dehiscence and floret opening. In this study,the dynamic changes in endogenous JA levels and expression of JA pathway genes in anthers 24-0 h before splitting were doserved to investigate the regulation of JA signaling before rice anther dehiscence.The result showed that the levels of JA and active conjugate jasmonoyl-isoleucine（JA-Ile） in anthers increased sharply from 2 h before the splitting.The JA and JA-Ile levels in splitting anthers were respectively 8.3 and 55 times than in ones of 2 h before splitting.Concurrently,the expression levels of OsLOX6,OsAOS1,OsAOC and OsOPR7 which encode enzymes involved in JA biosynthesis pathway were up-regulated partly from 24 to 0 h before anther dehiscence.The expression of OsJAR1 did not increased obviously and OsJAR2 decreased rapidly befor eanther dehiscence; these two homologous genes encode JA-Ile synthetase.The expression levels of OsCOI1 a,OsCOI1 b and OsCOI2 which encode JA signaling receptors were down-regulated slightly.However,the expression levels of OsJAZ10 and OsJAZ11,acting as repressors of JA signaling,increased 65 and 85 times from 24 to 0 h before anther dehiscence. These results indicated that the increase of JA level and differential activation of genes related in JA signaling pathway was closely correlated with the dehiscence program of rice anther.
作者
何永明
刘遂飞
雷抒情
HE Yong-ming, LIU Sui-fei, LEI Shu-qing(Jiangxi Agrieuhural University / Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Ministry of Education / Jiangxi Key Laboratory of Crop Physiology, Ecology and Genetic Breeding, Nanchang 330045, Chin)
出处
《江西农业大学学报》
CAS
CSCD
北大核心
2018年第3期429-434,共6页
Acta Agriculturae Universitatis Jiangxiensis
基金
国家自然科学基金项目(31360295)
江西省青年科学基金项目(20151BAB214014)~~
