沈阳农业大学水稻研究所,沈阳 110866
研究方向为水稻分子育种,E-mail: 1802660601@qq.com
徐 铨,水稻分子育种,E-mail: kobexu34@syau.edu.cn
国家重点研发计划(2024YFD1201000)
Rice Research Institute of Shenyang Agricultural University, Shenyang 110866
The National Key R&D Program of China (2024YFD1201000)
水稻是世界上最重要的粮食作物之一,其生长发育和产量会受到干旱胁迫的影响,因此发掘并鉴定水稻耐旱基因对培育水稻耐旱品种具有重要意义。本研究发现水稻JmjC家族基因JMJ715表达受到干旱胁迫诱导。转基因实验发现,与野生型(粳稻品种笹锦)相比,JMJ715敲除突变体株系对干旱胁迫处理更敏感,在复水后存活率显著降低,且干旱胁迫处理后的植株相对含水量显著减少。亚细胞定位结果显示,JMJ715定位在细胞核。启动子顺式作用元件分析发现,JMJ715基因启动子包括光响应、激素响应、胁迫响应等作用元件。实时荧光定量PCR结果显示,JMJ715在野生型笹锦各个组织中均有表达,其中在穗部和根部的表达量较高。干旱胁迫处理后的转录组测序结果显示,差异显著基因中有OsASR5、OsNR2等17个与干旱胁迫响应相关的已知基因。农艺性状调查结果显示,与野生型相比,正常生长条件下,JMJ715敲除突变体的穗数、每穗粒数、单株产量显著增加,而结实率、千粒重、粒形无显著变化。干旱处理后的JMJ715敲除突变体穗数、每穗粒数、单株产量等产量构成因素显著低于野生型。研究结果说明,JMJ715参与调控水稻耐旱性,并影响正常生长条件下水稻穗数、每穗粒数及单株产量。
Rice, as a globally important staple food crop, is highly vulnerable to drought stress, which adversely impacts its growth and yield. Therefore, identifying rice drought tolerance genes is of great significance for breeding drought-tolerant varieties. In this study, we found that the expression of JMJ715, a gene belonging to the rice JmjC family, is induced under drought stress. Transgenic experiments revealed that knockout mutants of JMJ715 in the japonica rice variety Sasanishiki (wild-type) exhibited increased sensitivity to drought stress, showing significantly lower survival rates after rewatering and reduced relative water content under stress conditions. Subcellular localization confirmed that JMJ715 is localized in the nucleus. Promoter analysis revealed the presence of cis-regulatory elements associated with light, hormone, stress responses in the JMJ715 promoter region. Quantitative Real-time PCR results showed that JMJ715 is expressed in various tissues of Sasanishiki, with the highest expression levels observed in panicles and roots. Transcriptome sequencing following drought stress treatment identified 17 known drought-responsive genes, including OsASR5 and OsNR2, among the significantly differentially expressed genes. Agronomic trait investigation under normal conditions showed that JMJ715 knockout mutants had significantly increased panicle number, grain number per panicle and grain yield per plant compared to the wild-type, while no significant differences were observed in seed setting rate, 1000-grain weight, or grain shape. In contrast, under drought stress conditions, the knockout mutants exhibited significantly reduced yield components, such as the panicle number, grain number per panicle, and grain yield per plant. Collectively, these findings revealed that JMJ715 is involved in regulating rice drought tolerance and influences panicle number, grain number per panicle and grain yield per plant under normal growth conditions.
王潇澈,于之雯,芦佳浩,等.水稻
