イネの低温回復と窒素利用効率を制御する「知的分子モジュール」を解明 (Researchers Uncover “Intelligent Molecular Module” for Rice Chilling Recovery and Nitrogen Use Efficiency)

2026-06-18 中国科学院(CAS)

中国科学院植物研究所のCHONG Kang教授らは、イネの低温障害回復と窒素利用効率を同時に制御する分子モジュール「CHPO(Chilling Phoenix)」を発見し、その成果をNature誌に発表した。気候変動に伴う寒波の増加と窒素肥料の過剰使用は、農業生産と環境保全の両面で課題となっている。本研究では、低温後の分げつ再生率を指標としてGWAS、QTL解析、マップベースクローニングを実施し、CHPOを同定した。CHPOは環境条件に応じて機能を切り替え、低温ストレス時には核内に蓄積して耐冷性関連遺伝子を活性化し、回復期には窒素輸送体遺伝子OsNRT2.4を活性化するとともにOsTCP19を抑制して窒素吸収と分げつ再生を促進する。さらに、中国の野生イネ由来の優良対立遺伝子CHPOjapは、収量および窒素利用効率を向上させることが確認された。本成果は、低温耐性と窒素利用効率を両立する気候変動適応型イネ品種の育種に有望な分子基盤を提供する。

イネの低温回復と窒素利用効率を制御する「知的分子モジュール」を解明 (Researchers Uncover “Intelligent Molecular Module” for Rice Chilling Recovery and Nitrogen Use Efficiency)
Figure: Molecular mechanism underlying the functional differences Between CHPOjap (left) and CHPOind (right). (Image by CAO Jie)

<関連情報>

CHPOはイネの低温回復と窒素利用を調整する CHPO coordinates chilling recovery and nitrogen use in rice

Jie Cao,Yunyuan Xu,Zhitao Li,Jingdan Han,Qian Qian,Song Ge,Hong Wang,Wei Luo & Kang Chong
Nature  Published:17 June 2026
DOI:https://doi.org/10.1038/s41586-026-10682-6

Abstract

Global rice production faces mounting challenges from abnormal temperature fluctuations and nitrogen-fertilizer-driven environmental pollution1,2,3,4,5,6,7. Developing varieties that balance chilling resilience and nitrogen-use efficiency (NUE) offers a promising solution, but the molecular networks coordinating these traits remain poorly understood. Here we identify CHILLING PHOENIX (CHPO), a major gene underlying the quantitative trait locus shared by both chilling tolerance and resilience. It encodes a MYB transcription factor that acts as a key regulator coordinating post-chilling recovery with nitrogen use in rice. Natural variation in a GCG-repeat-encoded polyalanine tract alters CHPO DNA-binding preference and redirects regulatory outputs between the japonica-type (CHPOjap) and indica-type (CHPOind), causing opposing effects on chilling tolerance and resilience. This allelic variation is shaped by domestication selection, with the CHPOjap allele probably derived from Chinese wild rice. CHPOjap directly targets OsTCP19 and OsNRT2.4 to fine-tune NUE, thereby enhancing chilling tolerance and resilience. These findings provide a mechanistic framework for a chilling-induced high-nitrogen-utilization module that alleviates the damage caused by chilling stress, and a potential molecular design strategy for breeding rice varieties with both chilling resilience and high NUE at the recovery stage.

1204農業及び蚕糸
ad
ad
Follow
ad
タイトルとURLをコピーしました