Genome-wide identification of heat shock protein 90 family in Larimichthys crocea and expression analysis in response to thermal stress and Vibrio parahaemolyticus infection.

Members of the heat shock protein 90 family (HSP90s) are evolutionarily conserved and play crucial roles in protein transport, immune regulation and antigen presentation. In this study, five hsp90s were identified from the genome of large yellow croaker (Larimichthys crocea) and analyzed using bioinformatics. All five identified hsp90s encode proteins with HATPase_c and HSP90 domains, and are mainly localized in the cytoplasm, mitochondria and endoplasmic reticulum. Chromosomal mapping revealed their distribution across three distinct chromosomes. Quantitative real-time PCR (qPCR) analysis showed differential expression patterns of the five hsp90s in 11 tissues. Additionally, their expression dynamics in the liver, spleen, head kidney, gill and blood were analyzed at 3 h, 12 h, 24 h and 48 h post thermal stress, Vibrio parahaemolyticus infection or under a combination of these two stressors. Results showed that the L. crocea hsp90s exhibited distinct expression patterns in response to the above three stimuli in different immune tissues. Notably, hsp90s in the spleen were most responsive. This study systematically clarified for the first time the gene structure characteristics, tissue expression patterns, and environmental stress response mechanisms of the HSP90 family in L. crocea. It confirmed that hsp90s show significant functional differentiation and synergy in response to biotic (pathogen infection) and abiotic (thermal stress) stresses, and provides important clues for a deeper understanding of the genetic basis of environmental adaptation in L. crocea.