Genome-wide identification and evolutionary diversification of TRP channels in Yesso scallop (Patinopecten...

Transient receptor potential (TRP) channels are a conserved family of non-selective cation channels that play key roles in sensing diverse environmental stimuli. However, comprehensive genome-wide characterization and regulatory analyses of TRP gene families in aquatic mollusks particularly after high temperature stress remain limited. In this study, a comprehensive genome-wide analysis was conducted on TRP channels in Yesso scallop (Patinopecten yessoensis) to elucidate their structural feature, evolutionary relationships, and transcriptional response to high temperature stress. A total of 33 PyTRP genes were identified and classified into four subfamilies (PyTRPM, PyTRPV, PyTRPA and PyTRPC). Among them, PyTRPM proteins exhibited lineage-specific motif compositions with the unique presence of Motif 6. Their mRNAs exhibited distinct expression profiles across developmental stages and adult tissues. Under high temperature stress, PyTRPM3-4 and PyTRPM8 exhibited contrasting transcriptional responses. PyTRPM3-4 exhibited a stress-inducible expression pattern, characterized by rapid upregulation during high temperature stress and early recovery, followed by a gradual return to baseline levels. In contrast, PyTRPM8 maintained high basal expression but was rapidly repressed after high temperature stress, accompanied by temperature-dependent alternative splicing that was reversible during recovery. Different PyTRP subfamilies exhibited lineage-specific duplication, distinct duplication patterns and divergent expression profiles. Together, these findings reveal distinct high-temperature-associated expression patterns of PyTRP genes and a skipped-exon event in PyTRPM8 in P. yessoensis, providing a basis for future functional studies.