Zhejiang Provincial Key Laboratory for Genetic Improvement and Quality Control of Medicinal Plants, College of Life and Environmental Science, Hangzhou Normal University, Hangzhou 311121, China.
Institute of Crop and Nuclear Technology Utilization, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China.
Int J Mol Sci. 2024 May 29;25(11):5950. doi: 10.3390/ijms25115950.
Salinity stress has a great impact on crop growth and productivity and is one of the major factors responsible for crop yield losses. The K-homologous (KH) family proteins play vital roles in regulating plant development and responding to abiotic stress in plants. However, the systematic characterization of the family in rice is still lacking. In this study, we performed genome-wide identification and functional analysis of family genes and identified a total of 31 genes in rice. According to the homologs of genes in , we constructed a phylogenetic tree with 61 genes containing 31 genes in and 30 genes in and separated them into three major groups. In silico tissue expression analysis showed that the genes are constitutively expressed. The qRT-PCR results revealed that eight genes responded strongly to salt stresses, and exhibited the strongest decrease in expression level, which was selected for further study. We generated the mutant via the CRISPR/Cas9 genome-editing method. Further stress treatment and biochemical assays confirmed that mutant was more salt-sensitive than Nip and the expression of several key salt-tolerant genes in was significantly reduced. Taken together, our results shed light on the understanding of the family and provide a theoretical basis for future abiotic stress studies in rice.
盐胁迫对作物生长和生产力有很大影响，是导致作物减产的主要因素之一。K-同源（KH）家族蛋白在植物发育调控和非生物胁迫响应中起着至关重要的作用。然而，水稻中 KH 家族的系统特征描述仍然缺乏。在这项研究中，我们进行了水稻 KH 家族基因的全基因组鉴定和功能分析，共鉴定出 31 个基因。根据 KH 基因在拟南芥中的同源物，我们构建了一个包含 31 个基因的系统发育树，并将其分为三大类。基因的计算机组织表达分析表明，这些基因是组成型表达的。qRT-PCR 结果表明，8 个 KH 基因对盐胁迫反应强烈，而 基因的表达水平下降最为明显，因此选择其进行进一步研究。我们通过 CRISPR/Cas9 基因组编辑方法产生了 基因的突变体。进一步的胁迫处理和生化分析证实，突变体比 Nip 更敏感，并且 基因中几个关键的耐盐基因的表达显著降低。总之，我们的研究结果阐明了 KH 家族的作用机制，为水稻未来的非生物胁迫研究提供了理论依据。
