光敏核不育水稻幼苗叶片脂氧合酶活性及其基因表达的昼夜变化

Diurnal Fluctuation of Lipoxygenase Activity and Its Gene Expression in Photo-Sensitive Genic Male Sterile Rice

为探查光敏核不育(PGMS)水稻中脂氧合酶(LOX)活性的光暗期变化特性,以PGMS水稻N5088S和D38S、常规水稻中早25、盐粳7号和中嘉早17及三系不育水稻G2A和东B11A为材料,在不同光周期(12L/12D、14L/10D和10L/14D)和光/暗期温度(30℃/30℃和30℃/26℃)下,研究了其幼苗叶片中LOX活性的昼夜变化,并采用RT-PCR方法对PGMS水稻幼苗叶片进行LOX基因的昼夜表达分析。结果表明,在所有光周期和培养温度处理下,PGMS水稻LOX活性均表现出暗期高而光期低的昼夜变化规律,但常规水稻和三系不育水稻的LOX活性均无明显的光暗期差异;暗期PGMS水稻LOX活性显著高于常规水稻和三系不育水稻。在12L/12D光周期和30℃/26℃(L/D)的培养温度下,检测的13个LOX基因中,检测到8个Os LOX基因,OsLOX2、Os LOX3、Os LOX4、Os LOX8和Os LOX13等基因的表达丰度在N5088S和/或D38S幼苗叶片中呈现暗期高光期低的趋势。因此,光敏核不育水稻N5088S和D38S幼苗叶片LOX活性及Os LOX家族的部分基因的表达具有明显的暗期高光期低的变化特征。

To investigate the change of lipoxygenase（ LOX） activity in light and dark periods in photo-sensitive genic male sterile（ PGMS） rice,PGMS rice N5088 S and D38 S,conventional rice Zhongzao25,Yanjing No.7 and Zhongjiazao17,and 3-line sterile rice G2 A and Dong B11 A were cultured in light incubator under different photoperiods（ 12 L / 12 D,14L / 10 D and 10 L / 14D） and different light / dark（ L / D） temperature regimes（ 30 ℃ / 30 ℃ and 30 ℃ / 26 ℃）,and the diurnal fluctuations of LOX activity in seedling leaves were analyzed.Also,the diurnal fluctuations of Os LOXs gene expression were analyzed with real-time RT-PCR method in PGMS rice.The results indicated that LOX activities in PGMS rice were higher in the dark period and lower in the light period under all the experiment conditions,while in conventional or 3-line sterile rice there were no significant differences between the light and dark periods. LOX activities in the dark period were higher in PGMS rice than that in conventional or 3-line sterile rice.Among the 13 LOX genes tested,8 Os LOX genes were detected,and the expression levels of Os LOX2,Os LOX3,Os LOX4,Os LOX8 and Os LOX13 trended to be higher in the dark period and lower in the light period in PGMS rice of N5088 S and / or D38 S under the conditions of30 ℃ / 26 ℃（ L / D） and 12 L / 12 D photoperiod.The study leads to a conclusion that seedling leaves of PGMS rice N5088 S and D38 S have a characterized diurnal fluctuation of a higher level in the dark period and a lower level in the light period in LOX activity and expressions of several Os LOXs.