The Role of Cold Shock Protein (CSP) Gene Family in Yak (Bos grunniens) for High-Altitude Adaptation: Genome-Wide Identification and Analysis.

Cold shock proteins (CSPs) play important roles in cellular adaptation to environmental stress. However, their characteristics and potential roles in yak (Bos grunniens), a species adapted to high-altitude environments, remain poorly understood. In this study, a genome-wide identification and comparative analysis of the CSP gene family was performed primarily using bioinformatics approaches based on publicly available genomic and transcriptomic datasets, along with a preliminary validation of their differential expression under cold and hypoxic stress. A total of 14 CSP genes were identified in the yak genome. Phylogenetic analysis across eight bovine species classified these genes into nine distinct clusters, revealing evolutionary conservation within the CSP family. Structural analyses showed variation in exon-intron organization and conserved motifs associated with stress responses. Protein-protein interaction (PPI) network analysis further suggested potential functional interactions between CSPs and key regulatory proteins. Tissue transcriptomic data indicated distinct expression patterns of CSP genes across multiple tissues. To provide experimental support for these findings, Reverse Transcription Quantitative Polymerase Chain Reaction (RT-qPCR) analysis was conducted in yak preadipocytes exposed to cold and hypoxic stress, revealing significant upregulation of several CSP genes. Together, these results provide a comprehensive overview of the CSP gene family in yak and offer insights into their potential roles in high-altitude adaptation in bovine species.