National Key Laboratory of Crop Genetic Improvement, Hubei Hongshan Laboratory, Huazhong Agricultural University, Wuhan, China.
Department of Biosciences, Durham University, South Road, Durham, DH1 3LE, UK.
BMC Biol. 2024 May 20;22(1):114. doi: 10.1186/s12915-024-01906-0.
Cotton is a major world cash crop and an important source of natural fiber, oil, and protein. Drought stress is becoming a restrictive factor affecting cotton production. To facilitate the development of drought-tolerant cotton varieties, it is necessary to study the molecular mechanism of drought stress response by exploring key drought-resistant genes and related regulatory factors.
In this study, two cotton varieties, ZY007 (drought-sensitive) and ZY168 (drought-tolerant), showing obvious phenotypic differences under drought stress, were selected. A total of 25,898 drought-induced genes were identified, exhibiting significant enrichment in pathways related to plant stress responses. Under drought induction, A subgenome expression bias was observed at the whole-genome level, which may be due to stronger inhibition of D subgenome expression. A gene co-expression module that was significantly associated with drought resistance was identified. About 90% of topologically associating domain (TAD) boundaries were stable, and 6613 TAD variation events were identified between the two varieties under drought. We identified 92 genes in ZY007 and 98 in ZY168 related to chromatin 3D structural variation and induced by drought stress. These genes are closely linked to the cotton response to drought stress through canonical hormone-responsive pathways, modulation of kinase and phosphatase activities, facilitation of calcium ion transport, and other related molecular mechanisms.
These results lay a foundation for elucidating the molecular mechanism of the cotton drought response and provide important regulatory locus and gene resources for the future molecular breeding of drought-resistant cotton varieties.
棉花是世界主要经济作物之一，也是天然纤维、油脂和蛋白质的重要来源。干旱胁迫已成为影响棉花生产的限制因素。为了促进抗旱棉花品种的发展，有必要通过探索关键抗旱基因和相关调控因子来研究干旱胁迫响应的分子机制。
本研究选择了两个棉花品种 ZY007（干旱敏感）和 ZY168（抗旱），它们在干旱胁迫下表现出明显的表型差异。共鉴定出 25898 个干旱诱导基因，这些基因在植物应激反应相关途径中显著富集。在干旱诱导下，全基因组水平上观察到 A 亚基因组表达偏向，这可能是由于 D 亚基因组表达受到更强的抑制。鉴定到与抗旱性显著相关的基因共表达模块。大约 90%的拓扑关联域（TAD）边界是稳定的，在干旱条件下，两个品种之间鉴定到 6613 个 TAD 变化事件。我们在 ZY007 中鉴定到 92 个与染色质 3D 结构变异相关的基因，在 ZY168 中鉴定到 98 个基因，这些基因受干旱胁迫诱导。这些基因通过经典激素响应途径、激酶和磷酸酶活性的调节、钙离子转运的促进以及其他相关的分子机制，与棉花对干旱胁迫的反应密切相关。
这些结果为阐明棉花干旱响应的分子机制奠定了基础，为未来抗旱棉花品种的分子育种提供了重要的调控位点和基因资源。
