Li Gang, Chen Ziqiang, Guo Xinrui, Tian Dagang, Li Chenchen, Lin Min, Hu Changquan, Yan Jingwan
Biotechnology Research Institute, Fujian Academy of Agricultural Sciences, Fuzhou 350003, China.
Plants (Basel). 2024 Sep 5;13(17):2488. doi: 10.3390/plants13172488.
DnaJ proteins, also known as HSP40s, play a key role in plant growth and development, and response to environmental stress. However, little comprehensive research has been conducted on the gene family in maize. Here, we identify 91 genes from maize, which are likely distributed in the chloroplast, nucleus, and cytoplasm. Our analysis revealed that were classified into three types, with conserved protein motifs and gene structures within the same type, particularly among members of the same subfamily. Gene duplication events have likely contributed to the expansion of the family in maize. Analysis of cis-regulatory elements in promoters suggested involvement in stress responses, growth and development, and phytohormone sensitivity in maize. Specifically, four cis-acting regulatory elements associated with stress responses and phytohormone regulation indicated a role in adaptation. RNA-seq analysis showed constitutive expression of most genes, some specifically in pollen and endosperm. More importantly, certain genes also responded to salt, heat, and cold stresses, indicating potential interaction between stress regulatory networks. Furthermore, early responses to heat stress varied among five inbred lines, with upregulation of almost tested genes in B73 and B104 after 6 h, and fewer genes upregulated in QB1314, MD108, and Zheng58. After 72 h, most genes in the heat-sensitive inbred lines (B73 and B104) returned to normal levels, while many genes, including ZmDnaJ55, 79, 88, 90, and 91, remained upregulated in the heat-tolerant inbred lines (QB1314, MD108, and Zheng58) suggesting a synergistic function for prolonged protection against heat stress. In conclusion, our study provides a comprehensive analysis of the family in maize and demonstrates a correlation between heat stress tolerance and the regulation of gene expression within this family. These offer a theoretical basis for future functional validation of these genes.
DnaJ蛋白，也被称为热休克蛋白40（HSP40），在植物生长发育以及对环境胁迫的响应中发挥关键作用。然而，针对玉米中该基因家族的全面研究较少。在此，我们从玉米中鉴定出91个基因，它们可能分布于叶绿体、细胞核和细胞质中。我们的分析表明，这些基因分为三种类型，同一类型内具有保守的蛋白质基序和基因结构，尤其是在同一亚家族成员之间。基因复制事件可能促使了玉米中该基因家族的扩张。对该基因启动子顺式作用元件的分析表明，它们参与了玉米的胁迫响应、生长发育以及植物激素敏感性。具体而言，四个与胁迫响应和植物激素调节相关联的顺式作用调控元件表明其在适应性方面发挥作用。RNA测序分析显示，大多数该基因呈组成型表达，有些基因在花粉和胚乳中特异性表达。更重要的是，某些基因也对盐、热和冷胁迫作出响应，表明胁迫调控网络之间存在潜在相互作用。此外，五个自交系对热胁迫的早期响应各不相同，B73和B104中几乎所有被测该基因在6小时后上调，而QB1314、MD108和郑58中上调的基因较少。72小时后，热敏感自交系（B73和B104）中的大多数该基因恢复到正常水平，而包括ZmDnaJ55、79、88、90和91在内的许多基因在耐热自交系（QB1314、MD108和郑58）中仍上调，这表明其具有协同功能，可长期抵御热胁迫。总之，我们的研究对玉米中该基因家族进行了全面分析，并证明了耐热性与该家族内基因表达调控之间的相关性。这些研究结果为这些基因未来的功能验证提供了理论基础。
