Photoperiod- and thermo-sensitive genic male sterility (PGMS and TGMS) are the core components for hybrid breeding in crops. Hybrid rice based on the two-line system using PGMS and TGMS lines has been successfully developed and applied widely in agriculture. However, the molecular mechanism underlying the control of PGMS and TGMS remains obscure. In this study, we mapped and cloned a major locus, p/tms12-1 (photo- or thermo-sensitive genic male sterility locus on chromosome 12), which confers PGMS in the japonica rice line Nongken 58S (NK58S) and TGMS in the indica rice line Peiai 64S (PA64S, derived from NK58S). A 2.4-kb DNA fragment containing the wild-type allele P/TMS12-1 was able to restore the pollen fertility of NK58S and PA64S plants in genetic complementation. P/TMS12-1 encodes a unique noncoding RNA, which produces a 21-nucleotide small RNA that we named osa-smR5864w. A substitution of C-to-G in p/tms12-1, the only polymorphism relative to P/TMS12-1, is present in the mutant small RNA, namely osa-smR5864m. Furthermore, overexpression of a 375-bp sequence of P/TMS12-1 in transgenic NK58S and PA64S plants also produced osa-smR5864w and restored pollen fertility. The small RNA was expressed preferentially in young panicles, but its expression was not markedly affected by different day lengths or temperatures. Our results reveal that the point mutation in p/tms12-1, which probably leads to a loss-of-function for osa-smR5864m, constitutes a common cause for PGMS and TGMS in the japonica and indica lines, respectively. Our findings thus suggest that this noncoding small RNA gene is an important regulator of male development controlled by cross-talk between the genetic networks and environmental conditions.
光周期和溫度敏感遺傳雄性不育（PGMS和TGMS）是作物雜交育種的核心元件?；赑GMS和TGMS的兩系雜交水稻已經(jīng)成功地發(fā)展和運用于農(nóng)業(yè)生產(chǎn)。但是對于PGMS和TGMS調(diào)控的分子遺傳機理還不清楚。本研究我們對引起粳稻品系農(nóng)墾58S（NK58S）PGMS和秈稻品系培矮64S（PA64S，由NK58S衍生而來）TGMS的主效座位p/tms12-1進行了定位和克隆?；パa實驗表明包含野生型P/TMS12-1等位基因的一個2.4kb的DNA片段能夠恢復NK58S和PA64S的花粉育性。P/TMS12-1編碼一個特異的非編碼RNA，產(chǎn)生21nt的小RNA，我們將之命名為osa-smR5864w。和P/TMS12-1相比，p/tms12-1中有一個C-G替換出現(xiàn)在突變型小RNA內(nèi)，我們將之命名為osa-smR5864m。此外，在NK58S和PA64S中過量表達一個375bp可以產(chǎn)生osa-smR5864w的P/TMS12-1序列也能回復花粉育性。這個小RNA主要在幼穗表達，但是其表達不受日長或溫度的顯著影響。我們的結(jié)果揭示了p/tms12-1中一個點突變導致了osa-smR5864m的功能喪失，這是分別引起粳稻和秈稻品系PGMS和TGMS的共同原因。因此我們的發(fā)現(xiàn)表明這個非編碼小RNA基因通過遺傳網(wǎng)絡和環(huán)境調(diào)節(jié)間的串話，是控制雄配子發(fā)育的一個重要調(diào)節(jié)因子。