Decoding thermal adaptation: genome-wide identification of TRP channel repertoire in cephalopods and gene expression responses to chronic thermal exposure in Sepia officinalis and Octopus maya embryos

Transient Receptor Potential (TRP) channels constitute a versatile family of membrane proteins central to sensory perception and a broad range of physiological functions. Conserved throughout evolution in both vertebrates and invertebrates, TRPs respond to diverse environmental stimuli, including temperature fluctuations, mechanical forces, osmotic changes, redox states, and chemical signals. In cephalopods—marine invertebrates renowned for their sophisticated sensory systems and behavioural complexity—the molecular mechanisms underlying thermal sensing remain poorly understood.In this study, we present the first genome-wide identification and phylogenetic classification of 92 TRP channel sequences from 12 cephalopod species, distributed among six canonical families: TRPA, TRPC, TRPM, TRPV, TRPML, and TRPP. We further analysed TRP gene expression under chronic thermal stress in embryos of Sepia officinalis and Octopus maya, two species occupying contrasting thermal niches.Our findings reveal a remarkably diverse TRP complement in cephalopods and identify αTRPC as the most consistently and robustly upregulated subtype in response to elevated temperature. Strikingly, αTRPC expression is markedly enriched in the eyes of both species, suggesting a potential integrative function in processing both thermal and visual cues—an adaptive feature likely beneficial in rapidly changing coastal environments. This work provides the first in-depth characterisation of TRP channels in cephalopods and advances our understanding of the molecular basis of thermal adaptation in marine invertebrates. These results lay a foundation for future functional investigations and contribute to a broader understanding of how cephalopod sensory systems may respond to ongoing ocean warming