AUTHOR=Sun Yalong , Wen Haishen , Tian Yuan , Mao Xuebin , Li Xiurong , Li Junjie , Hu Yanbo , Liu Yang , Li Jifang , Li Yun 

TITLE=HSP90 and HSP70 Families in Lateolabrax maculatus: Genome-Wide Identification, Molecular Characterization, and Expression Profiles in Response to Various Environmental Stressors

JOURNAL=Frontiers in Physiology

VOLUME=12

YEAR=2021

URL=https://www.frontiersin.org/journals/physiology/articles/10.3389/fphys.2021.784803

DOI=10.3389/fphys.2021.784803

ISSN=1664-042X

ABSTRACT=<p>Heat shock proteins (HSPs) are a large class of highly conserved chaperons, which play important roles in response to elevated temperature and other environmental stressors. In the present study, 5 <italic>HSP90</italic> genes and 17 <italic>HSP70</italic> genes were systematically characterized in spotted seabass (<italic>Lateolabrax maculatus</italic>). The evolutionary footprint of <italic>HSP</italic> genes was revealed via the analysis of phylogeny, chromosome location, and gene copy numbers. In addition, the gene structure features and the putative distribution of heat shock elements (HSEs) and hypoxia response elements (HREs) in the promoter regions were analyzed. The protein-protein interaction (PPI) network analyses results indicated the potential transcriptional regulation between the heat shock factor 1 (<italic>HSF1</italic>) and <italic>HSPs</italic> and a wide range of interactions among <italic>HSPs</italic>. Furthermore, quantitative (q)PCR was performed to detect the expression profiles of <italic>HSP90</italic> and <italic>HSP70</italic> genes in gill, liver, and muscle tissues after heat stress, meanwhile, the expression patterns in gills under alkalinity and hypoxia stresses were determined by analyzing RNA-Seq datasets. Results showed that after heat stress, most of the examined <italic>HSP</italic> genes were significantly upregulated in a tissue-specific and time-dependent manners, and <italic>hsp90aa1.1, hsp90aa1.2</italic>, <italic>hsp70.1</italic>, and <italic>hsp70.2</italic> were the most intense responsive genes in all three tissues. In response to alkalinity stress, 11 out of 13 significantly regulated <italic>HSP</italic> genes exhibited suppressed expression patterns. Alternatively, among the 12 hypoxia-responsive-expressed <italic>HSP</italic> genes, 7 genes showed induced expressions, while <italic>hsp90aa1.2</italic>, <italic>hsp70.1</italic>, and <italic>hsp70.2</italic> had more significant upregulated changes after hypoxic challenge. Our findings provide the essential basis for further functional studies of <italic>HSP</italic> genes in response to abiotic stresses in spotted seabass.</p>