Plant J|GORI，编码WD40域蛋白，是花粉管发芽和水稻伸长所需的
在高等植物中，精细胞成功地传递到胚囊是由花粉管的生长所介导的。作物花粉萌发和花粉管生长的分子机制尚不清楚，尽管这些机制对植物繁殖和种子形成至关重要。
通过筛选水稻（Oryza sativa）花粉特异性基因突变体，我们鉴定了一个水稻花粉萌发调节剂（GORI）的T-DNA插入突变体，该突变体的野生型（WT）与杂合子的分离比为1:1。GORI编码一个7-WD40-基序蛋白，与拟南芥中的JINGUBANG/REN4 同源。GORI在水稻花粉中特异表达，其蛋白定位于细胞核、细胞质和质膜。
此外，通过CRISPR-Cas9产生的纯合突变体gori-2明显表现出雄性不育，花粉管萌发和伸长受到破坏。
萌发的花粉管显示肌动蛋白丝减少和果胶分布改变。转录组分析显示，与野生型相比，gori-2中852个花粉特异性基因表达下调，基因本体富集分析表明这些基因与细胞壁修饰和网格蛋白外壳组装密切相关。
根据GORI的分子特征、对GORI突变体的表型观察及其与内吞蛋白和Rac-GTPase的相互作用，我们认为GORI在水稻花粉管生长过程中起着关键作用。
Successful delivery of sperm cells to the embryo sac in higher plants is mediated by pollen tube growth. The molecular mechanisms underlying pollen germination and tube growth in crop plants remain rather unclear, although these mechanisms are crucial to plant reproduction and seed formation. By screening pollen‐specific gene mutants in rice (Oryza sativa), we identified a T‐DNA insertional mutant of Germinating modulator of rice pollen (GORI) that showed a one‐to‐one segregation ratio for wild type (WT) to heterozygous. GORI encodes a seven‐WD40‐motif protein that is homologous to JINGUBANG/REN4 in Arabidopsis. GORI is specifically expressed in rice pollen, and its protein is localized in the nucleus, cytosol and plasma membrane. Furthermore, a homozygous mutant, gori‐2, created through CRISPR‐Cas9 clearly exhibited male sterility with disruption of pollen tube germination and elongation. The germinated pollen tube of gori‐2 exhibited decreased actin filaments and altered pectin distribution. Transcriptome analysis revealed that 852 pollen‐specific genes were downregulated in gori‐2 compared with the WT, and Gene Ontology enrichment analysis indicated that these genes are strongly associated with cell wall modification and clathrin coat assembly. Based on the molecular features of GORI, phenotypical observation of the gori mutant and its interaction with endocytic proteins and Rac GTPase, we propose that GORI plays key roles in forming endo‐/exocytosis complexes that could mediate pollen tube growth in rice.
https://onlinelibrary.wiley.com/doi/pdf/10.1111/tpj.15139?af=R
文章原创；转载请注明来源。
温馨提示：
为方便PaperRSS粉丝们科研、就业等话题交流。我们根据10多个专业方向（植物、医学、药学、人工智能、化学、物理、财经管理、体育等），特建立了30个国内外博士交流群。群成员来源欧美、日韩、新加坡、清华北大、中科院等全球名校。