茉莉素调控雄蕊发育的分子机理

The plant hormone jasmonate (JA) regulates diverse plant developmental processes, including stamen development, root growth, leaf senescence, and defense against insect attack and pathogen infections. The Arabidopsis and rice mutants with disruption in JA biosynthesis or signal transduction exhibit male sterility due to arrested stamen development, including failure of filament elongation, anther dehiscence and pollen maturation. It is scientifically valuable to address the molecular mechanism for JA-regulated stamen development. ..Recently, we revealed that, in response to JA signals, the F-box protein Coronatine Insensitive1 (COI1) recruits Jasmonate ZIM-domain (JAZ) proteins for degradation via the 26S proteasome, and the downstream R2R3-MYB factors MYB21 and MYB24 are released to activate gene expression for stamen development. However, little is known about the molecular mechanism for MYB21 and MYB24 in JA-regulated stamen development. The aim of the project is to isolate MYB21/MYB24-interaction proteins, and investigate their functional mechanism for regulation of stamen development. These novel findings will reveal the molecular basis of JA-regulated stamen development and male fertility, possess important scientific value and application prospects.

植物激素茉莉素调控雄蕊发育、根的生长、叶片衰老、次级代谢、以及对昆虫和病原菌的抗性。雄蕊是植物的雄性生殖器官，决定植物繁殖后代的能力。茉莉素调控雄蕊发育。拟南芥和水稻等植物的茉莉素缺失突变体和信号传导突变体因雄蕊发育缺陷表现为雄性不育：花丝不能正常伸长，花粉囊不能开裂，花粉没有活性。研究茉莉素调控雄蕊发育的分子机理具有重要的科学意义和应用价值。..我们先前的研究发现，茉莉素通过受体COI1降解JAZ蛋白，进而释放下游转录因子MYB21和MYB24促进雄蕊发育。本研究以拟南芥为材料，通过筛选MYB21/MYB24互作蛋白，获得茉莉素信号传导途径新组分，深入揭示茉莉素调控雄蕊发育的分子机理机理。该研究具有重要的科学价值和潜在应用前景。

雄蕊是植物的生殖器官，雄蕊的发育直接决定了植物的育性。我们利用生理、生化、遗传和分子生物学研究策略，揭示了茉莉素调控雄蕊发育的分子机制。该研究发现MYB转录因子MYB21/MYB24与IIIe bHLH转录因子（MYC2/MYC3/MYC4/MYC5）形成MYB-MYC转录复合体。IIIe bHLH转录因子（MYC2/MYC3/MYC4/MYC5）功能冗余地调控拟南芥的雄蕊发育，包括花丝伸长、花粉囊开裂和花粉成熟。myc2 myc3 myc4 myc5四突变体的雄蕊发育滞后。MYC5融合EAR抑制结构域的超表达植株表现为雄性不育。JAZ蛋白与MYB-MYC转录复合体互作抑制其活性。MYC超表达能够部分逃离JAZ抑制恢复coi1-1雄蕊的发育。该研究揭示了茉莉素诱导JAZ蛋白降解，释放MYB-MYC转录复合体，进而促进植物雄蕊发育的分子机制。.该研究揭示了一个新的复合体调控茉莉素介导的雄性生殖发育和育性，丰富了人们对生殖发育调控机理的认识，具有重要科学意义，为指导农业生产提供了重要参考。