State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China.
The Municipal Key Laboratory of the Molecular Genetics of Hybrid Wheat, Institute of Hybrid Wheat, Beijing Academy of Agriculture and Forestry Sciences, Beijing, 100097, China.
Sci China Life Sci. 2023 Feb;66(2):197-208. doi: 10.1007/s11427-022-2204-y. Epub 2022 Oct 11.
Phased small interfering RNAs (phasiRNAs) are abundantly expressed in anthers and linked to environment-related male fertility in grasses, yet how they function under different environmental conditions remains unclear. Here, we identified a rice (Oryza sativa) low temperature-induced Argonaute (AGO) protein, OsAGO1d, that is responsible for generating phasiRNAs and preserving male fertility at low temperature. Loss of OsAGO1d function causes low-temperature male sterility associated with delayed programmed cell death of tapetal cells during anther development. OsAGO1d binds miR2118 and miR2275 family members and triggers phasiRNA biogenesis; it also binds 21-nt phasiRNAs with a 5' terminal U. In total, phasiRNAs from 972 loci are OsAGO1d-dependent. OsAGO1d protein moves from anther wall cells into meiocytes, where it loads miR2275 to produce 24-nt phasiRNAs. Together, our results show that OsAGO1d acts as a mobile signal to fine-tune phasiRNA production and this function is important for male fertility at low temperature.
分相小干扰 RNA（phasiRNAs）在花药中大量表达，并与禾本科植物中与环境相关的雄性育性有关，但它们在不同环境条件下如何发挥作用尚不清楚。在这里，我们鉴定了一个水稻（Oryza sativa）低温诱导的 Argonaute（AGO）蛋白，OsAGO1d，它负责产生 phasiRNAs 并在低温下保持雄性育性。OsAGO1d 功能丧失导致低温雄性不育，与花药发育过程中绒毡层细胞程序性死亡延迟有关。OsAGO1d 结合 miR2118 和 miR2275 家族成员并触发 phasiRNA 的生物发生；它还结合具有 5'端 U 的 21-nt phasiRNAs。共有 972 个基因座的 phasiRNAs 依赖于 OsAGO1d。OsAGO1d 蛋白从花药壁细胞转移到减数分裂细胞，在那里它加载 miR2275 产生 24-nt phasiRNAs。总之，我们的研究结果表明，OsAGO1d 作为一种移动信号，精细调节 phasiRNA 的产生，这一功能对低温下的雄性育性至关重要。
