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. Keywords: rice; PGMS; TGMS; noncoding RNA; small RNA Cell Research (2012) IntroductionAsian cultivated rice (Oryza sativa L.) is one of the world's most important crops, meeting the stable food demand of more than half of the global population. The development of hybrid rice is a major approach for increasing the yield potential of rice, since hybrid rice varieties have about 20% or more yield advantage over improved inbred varieties [1]. Hybrid rice technologies are mainly based on the three-line and two-line systems. The three-line system uses cytoplasmic male sterility lines, maintainer lines and restorer lines [2,3]. The twoline hybrid rice is based on the discovery and application of environmentally sensitive genic male sterile (EGMS) lines, which serve as both the male sterile lines and maintainer lines under different environmental conditions [4]. Thus, the two-line hybrid rice system is an important innovation for the better exploitation of hybrid vigor (heterosis). Compared with the three-line system, the advantages of the two-line system include a wider range Rice PGMS and TGMS caused by a point mutation in a noncoding RNA 650 of germplasm resources used as breeding parents, better grain quality and higher yields, and benefiting from simpler procedures for breeding and hybrid seed production [5...

Thermosensitive genic male-sterile (TGMS) lines, which are male-sterile at restrictive (high) temperatures but male-fertile at permissive (low) temperatures, have been widely used in breeding two-line hybrid rice (Oryza sativa L.). Here we find that mutation of thermosensitive genic male sterile 5 (tms5) in rice causes the TGMS trait through a loss of RNase Z S1 function. We show that RNase Z S1 processes the mRNAs of three ubiquitin fusion ribosomal protein L40 (Ub L40 ) genes into multiple fragments in vitro and in vivo. In tms5 mutants, high temperature results in increased levels of Ub L40 mRNAs. Overaccumulation of Ub L40 mRNAs causes defective pollen production and male sterility. Our results uncover a novel mechanism of RNase Z S1 -mediated Ub L40 mRNA regulation and shows that loss of this regulation produces TGMS in rice, a finding with potential applications in hybrid crop breeding.

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This study was conducted to compare the microbiome and metabolome differences in the colon lumen from two pig breeds with different genetic backgrounds. Fourteen weaned piglets at 30 days of age, including seven Landrace piglets (a lean-type pig breed with a fast growth rate) and seven Meihua piglets (a fatty-type Chinese local pig breed with a slow growth rate), were fed the same diets for 35 days. Untargeted metabolomics analyses showed that a total of 401 metabolites differed between Landrace and Meihua. Seventy of these 401 metabolites were conclusively identified. Landrace accumulated more short-chain fatty acids (SCFAs) and secondary bile acids in the colon lumen. Moreover, expression of the SCFAs transporter (solute carrier family 5 member 8, SLC5A8) and receptor (G protein-coupled receptor 41, GPR41) in the colon mucosa was higher, while the bile acids receptor (farnesoid X receptor, FXR) had lower expression in Landrace compared to Meihua. The relative abundances of 8 genera and 16 species of bacteria differed significantly between Landrace and Meihua, and were closely related to the colonic concentrations of bile acids or SCFAs based on Pearson's correlation analysis. Collectively, our results demonstrate for the first time that there were differences in the colonic microbiome and metabolome between Meihua and Landrace piglets, with the most profound disparity in production of SCFAs and secondary bile acids.