bHLH57 confers chilling tolerance and grain yield improvement in rice

作者：Lin Zhang, Zhipan Xiang, Junfeng Li, Siyao Wang, Yi Chen, Yan Liu, Dandan Mao, Sheng Luan, Liangbi Chen · 发表于：Plant Cell & Environment · 年份：2022 · DOI：10.1111/pce.14513 · 被引用次数：52 · 研究领域：Genetic Mapping and Diversity in Plants and Animals、GABA and Rice Research、Rice Cultivation and Yield Improvement

Chilling stress has become a major limiting factor that reduces crop productivity worldwide. In this study, we identified a new gene bHLH57, whose product enhances chilling tolerance in rice at diverse developmental stages. bHLH57 was mainly expressed in leaves and anthers, and its protein was targeted to the nucleus. Overexpression of bHLH57 enhanced chilling tolerance by increasing trehalose synthesis, whereas its mutants by CRISPR/Cas9-mediated mutagenesis were more sensitive to chilling and had reduced trehalose. Meanwhile, bHLH57 may regulate ROS metabolism and CBFs/DREBs- dependent pathways in response to chilling stress. In addition, the overexpression of bHLH57 resulted in increased grain yield under normal and chilling conditions, however, the disruption of bHLH57 displayed decreased grain size and seed setting rate, thus reduced grain yield. Phylogenetic and nucleotide diversity analyses suggested that bHLH57 is relatively conserved in monocotyledons, and may be selected during indica populations adaptation. Taken together, we have identified a new bHLH regulator involved rice chilling tolerance and grain yield, and provide a potential target gene for improving chilling tolerance and grain yield of rice.