Genome-wide identification and temperature-responsive expression profiling of TRP gene family in red swamp crayfish (Procambarus clarkii)

Temperature variations significantly influence physiological processes in arthropod. The transient receptor potential (TRP) channels are key cellular sensors in the detection of temperature, pain, and mechanical stimuli. However, a comprehensive genome-wide identification and functional characterization of the TRP gene family in Procambarus clarkii has not yet been conducted.

In this study, we performed a genome-wide analysis and identified 29 TRP genes in P. clarkii, including 11 newly reported, which were classified into seven subfamilies: TRPA, TRPC, TRPP, TRPM, TRPML, TRPN, and TRPV. Phylogenetic analysis revealed a remarkable expansion of the TRPA subfamily in crayfish compared with insects. Tissue expression profiling demonstrated diverse transcriptional patterns of PclaTRP genes across different organs. Comparative transcriptome analysis under temperature stress further indicated that P. clarkii employs distinct molecular strategies to cope with thermal extremes: heat stress induces proteostasis disruption and biosynthetic suppression, whereas cold stress promotes controlled metabolic downregulation. Specifically, cold stress (10 °C) significantly modulated the expression of 9 PclaTRP genes (4 genes up-regulated and 5 genes down-regulated), whereas non-noxious (30 °C) and noxious heat (35 °C) challenges drastically affected the mRNA levels of 9 (6 genes up-regulated and 3 genes down-regulated) and 12 (10 genes up-regulated and 2 genes down-regulated) PclaTRP genes, respectively. Moreover, temperature-responsive alternative splicing events were identified in two key thermo-responsive candidate factors, PclaTRPA1 and PclaPain2, implicating them in thermosensation.

Together, these findings provide a comprehensive overview of the TRP gene family in P. clarkii, revealing their differential expression patterns and alternative splicing regulation under heat and cold challenges, and identifying candidate genes that warrant further investigation for temperature tolerance improvement in crayfish breeding.