State Key Laboratory for Protein and Plant Gene Research, Peking-Tsinghua Center for Life Sciences, School of Life Sciences, Peking University, Beijing 100871, China.
National Plant Gene Research Center (Beijing), Beijing 100101, China.
J Integr Plant Biol. 2017 Sep;59(9):629-641. doi: 10.1111/jipb.12572.
Two yeast Brix family members Ssf1 and Ssf2, involved in large ribosomal subunit synthesis, are essential for yeast cell viability and mating efficiency. Their putative homologs exist in the Arabidopsis genome; however, their role in plant development is unknown. Here, we show that Arabidopsis thaliana SNAIL1 (AtSNAIL1), a protein sharing high sequence identity with yeast Ssf1 and Ssf2, is critical to mitosis progression of female gametophyte development. The snail1 homozygous mutant was nonviable and its heterozygous mutant was semi-sterile with shorter siliques. The mutation in SNAIL1 led to absence of female transmission and reduced male transmission. Further phenotypic analysis showed that the synchronic development of female gametophyte in the snail1 heterozygous mutant was greatly impaired and the snail1 pollen tube growth, in vivo, was also compromised. Furthermore, SNAIL1 was a nucleolar-localized protein with a putative role in protein synthesis. Our data suggest that SNAIL1 may function in ribosome biogenesis like Ssf1 and Ssf2 and plays an important role during megagametogenesis in Arabidopsis.
两个酵母 Brix 家族成员 Ssf1 和 Ssf2，参与大亚基核糖体的合成，对酵母细胞的存活和交配效率至关重要。它们的假定同源物存在于拟南芥基因组中；然而，它们在植物发育中的作用尚不清楚。在这里，我们表明拟南芥 SNAIL1（AtSNAIL1），一种与酵母 Ssf1 和 Ssf2 具有高度序列同一性的蛋白质，对雌性配子体发育的有丝分裂进程至关重要。snail1 纯合突变体是不可存活的，其杂合突变体是半不育的，蒴果较短。SNAIL1 的突变导致雌性传递缺失和雄性传递减少。进一步的表型分析表明，snail1 杂合突变体中雌性配子体的同步发育受到严重损害，体内的 snail1 花粉管生长也受到损害。此外，SNAIL1 是一种定位于核仁的蛋白质，具有参与蛋白质合成的假定作用。我们的数据表明，SNAIL1 可能像 Ssf1 和 Ssf2 一样在核糖体生物发生中发挥作用，并在拟南芥的大配子发生中发挥重要作用。
