Wang Qian, Sun Wenjing, Duan Yipei, Xu Yikun, Wang Huiyu, Hao Jinghong, Han Yingyan, Liu Chaojie
College of Plant Science and Technology, Beijing University of Agriculture, Beijing 102206, China.
College of Food Science and Engineering, Shandong Agricultural University, Taian 271018, China.
Int J Mol Sci. 2024 Dec 26;26(1):102. doi: 10.3390/ijms26010102.
The heat shock protein 70 (HSP70) family plays an important role in the growth and development of lettuce and in the defense response to high-temperature stress; however, its bioinformatics analysis in lettuce has been extremely limited. Genome-wide bioinformatics analysis methods such as chromosome location, phylogenetic relationships, gene structure, collinearity analysis, and promoter analysis were performed in the gene family, and the expression patterns in response to high-temperature stress were analyzed. The mechanism of in heat resistance in lettuce was studied by virus-induced gene silencing (VIGS) and transient overexpression techniques. The results showed that a total of 37 genes were identified by the Hidden Markov Model (HMM) and Protein Family Database (Pfam). These 37 genes were classified into groups A, B, C, and D by phylogenetic relationships. They were mainly localized on seven chromosomes except for chromosome 3; gene structure analysis showed that contained 1-9 exons, and the protein structure domains of genes in the same group were highly conserved. The covariance analysis showed that nine pairs of genes existed between members, and lettuce and sunflower had been more conserved in the evolutionary process. The promoter analysis showed that there were a large number of cis-acting elements related to phytohormones, growth, development, stress, and light response in . In addition, the results of the expression pattern analysis for all genes under high-temperature stress showed that 28 out of 37 genes were able to respond to heat stress, and only , , , , and were able to respond rapidly to heat stress (2 h). The expression of was higher at different periods under high-temperature stress; the overexpression of , the plant fresh weight, and the root weight were better than the control (CK); and the heat resistance was better. These results suggest that may play an important role under high-temperature stress in lettuce.
热休克蛋白70（HSP70）家族在生菜的生长发育以及对高温胁迫的防御反应中发挥着重要作用；然而，其在生菜中的生物信息学分析极其有限。本研究对该基因家族进行了全基因组生物信息学分析，包括染色体定位、系统发育关系、基因结构、共线性分析和启动子分析，并分析了其对高温胁迫的响应表达模式。通过病毒诱导基因沉默（VIGS）和瞬时过表达技术研究了生菜耐热性的机制。结果表明，通过隐马尔可夫模型（HMM）和蛋白质家族数据库（Pfam）共鉴定出37个HSP70基因。根据系统发育关系，将这37个基因分为A、B、C和D组。它们主要定位在除3号染色体外的7条染色体上；基因结构分析表明，HSP70基因含有1-9个外显子，同一组基因的蛋白质结构域高度保守。共线性分析表明，生菜HSP70成员之间存在9对同源基因，且生菜HSP70与向日葵HSP70在进化过程中较为保守。启动子分析表明，生菜HSP70启动子中存在大量与植物激素、生长、发育、胁迫和光响应相关的顺式作用元件。此外，对所有HSP70基因在高温胁迫下的表达模式分析结果表明，37个HSP70基因中有28个能够响应热胁迫，只有Hsp70-1、Hsp70-2、Hsp70-5、Hsp70-6和Hsp70-25能够快速响应热胁迫（2小时）。Hsp70-2在高温胁迫下不同时期的表达量均较高；过表达Hsp70-2后，植株鲜重和根重均优于对照（CK），耐热性更好。这些结果表明，Hsp70-2在生菜高温胁迫下可能发挥重要作用。
