OsCathB调节萌发水稻种子糊粉层PCD的发生  

OsCathB Regulates the Occurrence of Programmed Cell Death in the Aleurone Layers of Germinating Rice Seeds

作　　者：李哲[1] 陈茹猛 陈惠萍[1] Li Zhe;Chen Rumeng;Chen Huiping(School of Life Sciences,Hainan University,Haikou,570228)

机构地区：[1]海南大学生命科学学院,海口570228

出　　处：《分子植物育种》2022年第4期1163-1169,共7页Molecular Plant Breeding

基　　金：国家自然科学基金项目(31960453,31560426)资助。

摘　　要：本研究以水稻日本晴(Oryza sativa L.spp.japonica)种子为材料,通过酶标法、实时荧光定量PCR技术及激光共聚焦扫描显微技术,对组织蛋白酶B(cathepsin B,CathB)活性、CathB1表达水平、caspase活性及水稻糊粉层细胞存活率等进行测定与分析,初步探讨CathB在调节萌发水稻种子糊粉层细胞程序性死亡(programmed cell death,PCD)中的作用。结果表明:在水稻种子萌发初期,糊粉层细胞中CathB的活性水平及其基因转录水平呈现时间依赖性,而且CathB专一性抑制剂CA074和caspase-3专一性抑制剂Ac-DEVD-CHO均可显著抑制CathB的活性和caspase-3的活性,但对caspase-1的活性无影响。此外,这两种抑制剂均可显著降低糊粉层细胞死亡的数目。以上结果证实,CathB在萌发水稻种子中发挥类似caspase-3的活性,且与具有类似caspase-3活性的蛋白酶一起调节糊粉层PCD的发生。该结果为进一步研究水稻种子萌发过程糊粉层PCD发生的分子机制提供了理论依据。In this study,with rice Nihonbare(Oryza sativa L.spp.japonica)seeds as the material,Cathepsin B(CathB)activity,CathB1 expression level,caspase activities and cell viability were determined in rice aleurone layers.The results showed that the levels of CathB activity and CathB1 gene transcript were time-dependent in aleurone cells at the early germination stage of rice seeds.Moreover,both CathB activity and caspase-3 activity were significantly inhibited by CA074(the CathB specific inhibitor)and Ac-DEVD-CHO(the caspase-3 specific inhibitor).However,the inhibitors had no effects on the activity of caspase-1.Furthermore,both inhibitors significantly reduced the number of dead cells in rice aleurone layers.The above results confirmed that CathB exerts caspase-3 activity in the aleurone cells of germinating rice seeds,and together with a protease with similar caspase-3activity,regulating the occurrence of PCD in the aleurone layers.The results provide a theoretical basis for further research on the molecular mechanism of PCD occurrence in aleurone layers during the germination of rice seeds.

关 键 词：组织蛋白酶B 水稻糊粉层 细胞程序性死亡 CASPASE-3 

分 类 号：S511[农业科学—作物学]