Integrated Transcriptomic and Proteomic Analyses Reveal a Diverse Venom Repertoire in Macrothele guizhouensis

Abstract The venom of spiders in the family Macrothelidae is a rich source of bioactive molecules with potential biomedical and agricultural applications, yet the venom composition of Macrothele guizhouensis remains poorly understood. Here, integrated transcriptomic and proteomic analyses were used to characterize its venom repertoire. Venom-gland transcriptomics identified diverse toxin-related transcripts, including cysteine-rich peptides (CRPs) and venom-associated proteins, while proteomics confirmed multiple secreted venom components. RT-qPCR analysis of representative toxin genes provided additional descriptive evidence for their expression patterns in the venom gland. Structural and evolutionary analyses revealed both conserved toxin scaffolds shared with related Macrothele species and divergent, lineage-specific peptides that may represent novel toxin variants. Several CRPs displayed structural features resembling those of known ion-channel-modulating toxins, including a double-knot peptide that represents a candidate for future functional investigation. These findings provide the first comprehensive molecular characterization of M. guizhouensis venom, expand current knowledge of toxin diversity and evolution in Macrothelidae, and establish a foundation for the discovery and functional characterization of bioactive peptides with pharmaceutical and pest-management potential.