植物真核细胞转化启动因子3子单元E的域架构控制了与转化 cis 元素的相互作用,以调节花粉管生长
Vinod Kumar1,2, Rémy Merret3, Marie C Carpentier4
1Laboratory of Pollen Biology, Institute of Experimental Botany of the Czech Academy of Sciences, Prague 6 165 00, Czech Republic.
The Plant cell
|February 17, 2026
概括
细胞转化启动因子3亚单元E (eIF3E) 通过结合特定的mRNA动机来调节基因表达. 它的PCI域和酸化对于控制翻译和植物生育是至关重要的.
科学领域:
- 分子生物学分子生物学
- 植物科学 植物科学
- 遗传学 是一个遗传学.
背景情况:
- 细胞转化启动因子3亚单元E (eIF3E) 对于维持转化平衡至关重要.
- 控制eIF3E在转化平衡中的作用的精确机制尚未完全理解.
研究的目的:
- 阐明eIF3E在调节mRNA翻译中的结构和功能机制.
- 调查PCI域和eIF3E功能中的特定酸化位点的作用.
主要方法:
- 在烟草花粉管中的亲缘RNA免疫沉降测序 (RIP-seq).
- mRNA 记者测定. mRNA 记者测定.
- 阿尔法Fold3结构建模和福斯特共振能量转移 (FRET) 验证.
主要成果:
- 在真核生物中保存了eIF3E域架构和酸化位点 (Thr417,Ser421).
- 删除PCI域会破坏核定位,eIF3E-eIF3L相互作用和多体分裂.
- 鉴定了由eIF3E调节的mRNA基因 (MC1-MC3),作为翻译抑制剂和增强剂.
- PCI域删除或酸突变减弱了eIF3E-eIF3L相互作用,损害了MC2记者的翻译激活.
- 丢失PCI域或酸突变会错误调节花粉管生长和膜组织.
结论:
- eIF3E作为一种选择性的mRNA转化调节剂,将cis-motif识别与膜完整性和花粉管生长相结合.
- PCI域和酸化部位对于eIF3E在转化控制和确保植物肥沃性的功能至关重要.
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