Heat shock proteins gene family: Genome-wide identification in Micropterus salmoides and expression analysis under high-temperature stress

Micropterus salmoides has become one of the most important freshwater fish cultured in China. However, high temperatures during summer months lead to stress and even death of M. salmoides. Therefore, temperature is considered one of the important factors affecting the large-scale breeding of this species. Heat shock proteins (HSP) are a class of highly conserved proteins that are produced at high temperatures and under other stressful conditions. The present study aimed to explore the role of the HSP gene family in M. salmoides in response to high-temperature conditions. The genome-wide data for 62 HSP genes was obtained for this purpose, and the gene structure, chromosome location, and protein physicochemical properties were predicted. In addition, the expression patterns of these HSP genes in different tissues and under transient high-temperature stress were analyzed. The results revealed significant differences in the number of introns and motifs of the evaluated 62 HSP genes, which were distributed unevenly across 16 scaffolds. In response to high-temperature stress, the expression patterns of these 62 HSP were significantly upregulated or downregulated. Therefore, to further explore the expression patterns of these genes, qRT-PCR analysis was performed using 4 representative genes. The results revealed that although the 4 genes exhibited different expression patterns in different tissues, the genes were similar in terms of the overall expression pattern. These findings would serve as a basis for future studies comprehensively exploring the mechanism underlying the role of the HSP gene family in the response to heat stress in M. salmoides.