Zhang Shaowei, An Xueli, Jiang Yilin, Hou Quancan, Ma Bin, Jiang Qingping, Zhang Kai, Zhao Lina, Wan Xiangyuan
Research Institute of Biology and Agriculture, School of Chemistry and Biological Engineering, University of Science and Technology Beijing, Beijing, 100083, China.
Zhongzhi International Institute of Agricultural Biosciences, Beijing, 100083, China.
Nat Commun. 2024 Dec 30;15(1):10857. doi: 10.1038/s41467-024-55208-8.
Lipid metabolism is critical for male reproduction in plants. Many lipid-metabolic genic male-sterility (GMS) genes function in the anther tapetal endoplasmic reticulum, while little is known about GMS genes involved in de novo fatty acid biosynthesis in the anther tapetal plastid. In this study, we identify a maize male-sterile mutant, enr1, with early tapetal degradation, defective anther cuticle, and pollen exine. Using genetic mapping, we clone a key GMS gene, ZmENR1, which encodes a plastid-localized enoyl-acyl carrier protein (ACP) reductase. ZmENR1 interacts with β-hydroxyacyl-ACP dehydratase (ZmHAD1) to enhance the efficiency of de novo fatty acid biosynthesis. Furthermore, the ZmENR1/ZmHAD1 complex is regulated by a Maize Male Sterility 1 (ZmMS1)-mediated feedback repression loop to ensure anther cuticle and pollen exine formation by affecting the expression of cutin/wax- and sporopollenin-related genes. Intriguingly, homologous genes of ENR1 from rice and Arabidopsis also regulate male fertility, suggesting that the ENR1-mediated pathway likely represents a conserved regulatory mechanism underlying male reproduction in flowering plants.
脂质代谢对植物雄性生殖至关重要。许多脂质代谢基因雄性不育（GMS）基因在花药绒毡层内质网中发挥作用，而对于参与花药绒毡层质体中从头脂肪酸生物合成的GMS基因却知之甚少。在本研究中，我们鉴定出一个玉米雄性不育突变体enr1，其具有早期绒毡层降解、有缺陷的花药表皮和花粉外壁。通过遗传定位，我们克隆了一个关键的GMS基因ZmENR1，它编码一种定位于质体的烯酰-酰基载体蛋白（ACP）还原酶。ZmENR1与β-羟酰基-ACP脱水酶（ZmHAD1）相互作用，以提高从头脂肪酸生物合成的效率。此外，ZmENR1/ZmHAD1复合物受玉米雄性不育1（ZmMS1）介导的反馈抑制环调控，通过影响角质/蜡质和孢粉素相关基因的表达来确保花药表皮和花粉外壁的形成。有趣的是，水稻和拟南芥中ENR1的同源基因也调控雄性育性，这表明ENR1介导的途径可能代表了开花植物雄性生殖背后一种保守的调控机制。
