生物技术通报 ›› 2024, Vol. 40 ›› Issue (11): 152-161.doi: 10.13560/j.cnki.biotech.bull.1985.2024-0405

• 研究报告 • 上一篇    下一篇

水稻OsRhoGDI1过表达影响粒型及种子活力

戚旺(), 毕一凡, 轩强兵, 张新, 周慧岗, 聂圆情, 程彪彪, 张禹舜, 王俊杰, 梁卫红()   

  1. 河南师范大学生命科学学院,新乡 453000
  • 收稿日期:2024-04-28 出版日期:2024-11-26 发布日期:2024-12-19
  • 通讯作者: 梁卫红,女,博士,教授,研究方向:水稻发育分子细胞生物学;E-mail: liangwh@htu.edu.cn
  • 作者简介:戚旺,男,硕士研究生,研究方向:细胞信号转导及生理功能;E-mail: 1322496124@qq.com
    第一联系人:

    毕一凡为本文共同第一作者

  • 基金资助:
    国家自然科学基金项目(32201248);河南省科技研发计划联合基金(222301420106);河南省重点研发与推广专项(242102111164);河南省自然科学基金青年基金项目(222300420202);河南省高等学校重点科研项目(23A180020)

Overexpression of OsRhoGDI1 Gene Regulates Grain Shape and Seed Vigor in Rice

QI Wang(), BI Yi-fan, XUAN Qiang-bing, ZHANG Xin, ZHOU Hui-gang, NIE Yuan-qing, CHENG Biao-biao, ZHANG Yu-shun, WANG Jun-jie, LIANG Wei-hong()   

  1. College of Life Sciences, Henan Normal University, Xinxiang 453000
  • Received:2024-04-28 Published:2024-11-26 Online:2024-12-19

摘要:

【目的】 水稻OsRhoGDI1是前期利用酵母双杂交技术从幼穗中分离的一个与Rho/Rop蛋白OsRac5相互作用蛋白的编码基因,预期编码一种功能未知的Rho GDP解离抑制因子,采用转基因技术鉴定该基因的功能,为后续研究OsRhoGDI1与OsRac5在水稻生长发育中的功能奠定基础。【方法】 构建OsRhoGDI1过表达载体,转化水稻筛选阳性植株,对转基因水稻粒型和萌发特征开展分析,通过RT-qPCR分析粒型调控基因在籽粒发育中的表达,采用扫描电镜检测颖壳细胞特征;比较转基因水稻和对照水稻的萌发特征,并采用RT-qPCR检测GA和ABA合成、分解相关基因,以及α-淀粉酶基因在萌发种子中的相对表达水平,开展α-淀粉酶定性及定量分析。【结果】 与对照水稻相比,OsRhoGDI1过表达水稻的粒长极显著增加,粒宽、粒厚和千粒重均极显著降低,粒型调控基因GS2GS5GS6GLW7在水稻幼穗中的表达水平均不同程度地降低,而GW2表达水平提高;转基因水稻外颖壳细胞的长度增加、宽度降低。转基因水稻种子萌发早于对照,且GA合成基因、ABA分解基因及α-淀粉酶基因的表达水平均不同程度提高,而GA分解基因与ABA合成基因表达水平降低;α-淀粉酶活性在转基因水稻种子萌发过程中显著提高。【结论】 OsRhoGDI1过表达通过改变粒型调控基因表达水平,导致颖壳表皮细胞伸长,引起粒长变长,粒宽变窄;同时该基因过表达还通过改变萌发相关基因表达水平,提高α-淀粉酶活性,促进种子萌发。

关键词: 水稻, OsRhoGDI1, 粒型, 萌发, 激素, α-淀粉酶

Abstract:

【Objective】 OsRhoGDI1, a rice RhoGDI gene, was isolated from young panicles through yeast two-hybrid screening, using Rho/Rop protein OsRac5 as bait. RhoGDIs genes encode Rho GDP dissociation inhibitors, which negatively regulate the activities of Rho proteins. Transgenic technology was applied to identify the functions of OsRhoGDI1, aiming to lay a foundation for further research on the functional relationship between OsRhoGDI1 and OsRac5 in rice growth and development. 【Method】 OsRhoGDI1-overexpressed vector was constructed, and rice were transformed to obtain positive transgenic plants. The grain shape and germination characteristics of transgenic rice was analyzed. The expressions of grain-shape-regulating genes in grain development were detected through RT-qPCR, and scanning electron microscopy was used to detect the characteristics of glume cells. The germination characteristics were compared between OsRhoGDI1-overexpressed rice and control, and the expressions of the genes involved in synthesis and metabolism of gibberellin(GA)and abscisic acid(ABA)were detected by RT-qPCR, as well as the expressions and activities of α-amylases. 【Result】 Compared with the control rice, the OsRhoGDI1-overexpressed rice showed a significant increase in grain length, decrease in grain width, thickness and thousand grain weight. The expressions of grain-shape-regulating gene GS2, GS5, GS6 and GLW7 in young panicles also reduced to varying degrees, while the expression of GW2 increased. The lengths of glume cells in the transgenic rice increased, while the width decreased. The germination of transgenic rice was earlier than that of control, and the expressions of GA synthesis genes, ABA catabolic genes, and α-amylase genes increased to varying degrees, while the expressions of GA catabolic genes and ABA synthesis genes decreased. α-amylase activities were also enhanced in the transgenic rice, compared to the control. 【Conclusion】 The overexpression of OsRhoGDI1 gene regulates rice grain shape by altering the expressions of grain shape genes, leading to elongation of glume epidermal cells, resulting in increase of grain length and decrease of grain width. Meanwhile, the overexpression of this gene also changes the expressions of germination-related genes, increase the activities of α-amylase, thus enhance seed vigor and promote germination.

Key words: rice, OsRhoGDI1, grain shape, germination, hormones, α-amylase