Phased small-interfering RNAs (phasiRNAs) are a special class of small RNAs, which are generated in 21- or 24-nt intervals from transcripts of precursor RNAs. Although phasiRNAs have been found in a range of organisms, their biological functions in plants have yet to be uncovered. Here we show that phasiRNAs generated by the photopheriod-sensetive genic male sterility 1 (Pms1) locus were associated with photoperiod-sensitive male sterility (PSMS) in rice, a germplasm that started the two-line hybrid rice breeding. The Pms1 locus encodes a long-noncoding RNA PMS1T that was preferentially expressed in young panicles. PMS1T was targeted by miR2118 to produce 21-nt phasiRNAs that preferentially accumulated in the PSMS line under long-day conditions. A single nucleotide polymorphism in PMS1T nearby the miR2118 recognition site was critical for fertility change, likely leading to differential accumulation of the phasiRNAs. This result suggested possible roles of phasiRNAs in reproductive development of rice, demonstrating the potential importance of this RNA class as regulators in biological processes.
阶段性的小干扰RNA（phasiRNAs）是一类特殊的的小RNA，是由前体RNAs的转录本以21或24-nt间隔产生的。尽管已经在大量生物中发现phasiRNAs，但是它们在植物中的生物功能仍没有报道。本文，我们发现phasiRNAs由Pms1位点产生，Pms1与水稻的光周期敏感的雄性不育（PSMS）相关，这是开始两系杂交水稻育种的一种种质资源。Pms1位点编码一个长链非编码RNA PMS1T，它在幼穗中偏好性表达。PMS1T受到miR2118作用，产生21-nt phasiRNAs，在长日照条件下的PSMS株系中偏好性积累。PMS1T中miR2118识别位点附近的一个单碱基多态性对育性变化十分关键，可能导致phasiRNAs积累差异。这些结果表明，phasiRNAs在水稻生殖发育中可能的作用，表明这类RNA作为调控因子在生物过程中的潜在重要性。