Abstract
Labeo rohita, a commercially important Indian major carp, undergoes significant physiological and molecular alterations under cold stress. This Data Descriptor presents comprehensive proteomic and hormonal data capturing the fish's adaptive response to prolonged sub-lethal low temperature exposure (5-10 °C for 45 days). High-resolution LC-MS/MS analysis of serum and albumin-depleted serum revealed extensive proteome remodelling, indicating mechanisms of metabolic reprogramming, immune modulation, and post-translational regulation. A total of 598 proteins were identified in serum from cold-stressed fish and 335 in controls, while 1372 proteins were detected in albumin-depleted serum of stressed fish and 462 in controls, from 75,406 MS/MS spectra. In serum, 99 proteins were unique to controls, 75 to stressed fish, and 133 were shared; in albumin-depleted serum, 652 proteins were unique to controls, 366 to stressed fish, and 190 were common to both. Differentially expressed proteins were associated with energy metabolism, cytoskeletal organization, and cellular stress responses, highlighting key adaptive pathways. Hormonal profiling indicated reduced levels of thyroxine (T4), triiodothyronine (T3), and cortisol, alongside elevated estradiol and testosterone. GO enrichment analysis of DEPs revealed significant shifts in metabolic, stress response, and cellular homeostasis pathways. Together, these data offer a molecular framework for understanding cold adaptation in L. rohita, with implications for stress biomarker discovery and enhancing aquaculture resilience under climate variability.