Nitrogen nutrition contributes to plant fertility by affecting meiosis initiation

第一作者：Han Yang

第一单位：中科院遗传与发育生物学研究所

第一通讯：Zhukuan Cheng

Abstarct

背景回顾：Nitrogen (N), one of the most important plant nutrients, plays crucial roles in multiple plant developmental processes. Spikelets are the primary sink tissues during reproductive growth, and N deficiency can cause floral abortion.

氮是植物营养元素中最重要元素之一，在多个植物发育过程中发挥重要作用。穗状花序是水稻生殖生长过程中最主要的“库”组织，而氮缺乏会导致花败育。

提出问题：However, the roles of N nutrition in meiosis, the crucial step in plant sexual reproduction, are poorly understood.

但是，氮营养元素在植物有性生殖最关键一步，即减数分裂中的作用仍不清楚。

主要发现：Here, we identified an N-dependent meiotic entrance mutant with loss of function of ELECTRON TRANSFER FLAVOPROTEIN SUBUNIT β (ETFβ) in rice (Oryza sativa).

本文中，作者鉴定了水稻的一个氮依赖性的进入减数分裂突变体，即ETFβ基因功能缺失突变体。

结果1-etfβ表型：etfβ displayed meiosis initiation defects, excessive accumulation of branched-chain amino acids (BCAAs) and decrease in total N contents in spikelets under N starvation, which were rescued by applying excess exogenous inorganic N.

etfβ突变体在氮饥饿时，表现出减数分裂起始缺陷，积累过多的支链氨基酸，以及小穗中总氮含量降低的表型，这些表型缺陷均能够通过外施无机氮进行拯救。

结果2-ETFβ作用机制：Under N starvation, ETFβ, through its involvement in BCAA catabolism, promotes N reutilization and contributes to meeting N demands of spikelets, highlighting the impact of N nutrition on meiosis initiation.

在氮饥饿条件下，ETFβ通过参与支链氨基酸的分解代谢，促进植物体内的氮回收利用，以满足小穗对氮的需求，表明氮对于减数分裂起始具有重要作用。

结论：We conclude that N nutrition contributes to plant fertility by affecting meiosis initiation.

本文的研究结果揭示了氮营养元素通过影响减数分裂起始作用于植物的育性。