Sexually dimorphic venom proteins in long-jawed orb-weaving spiders ( Tetragnatha) comprise novel gene families

PeerJ. 2018 Jun 1;6:e4691. doi: 10.7717/peerj.4691. eCollection 2018.

Abstract

Venom has been associated with the ecological success of many groups of organisms, most notably reptiles, gastropods, and arachnids. In some cases, diversification has been directly linked to tailoring of venoms for dietary specialization. Spiders in particular are known for their diverse venoms and wide range of predatory behaviors, although there is much to learn about scales of variation in venom composition and function. The current study focuses on venom characteristics in different sexes within a species of spider. We chose the genus Tetragnatha (Tetragnathidae) because of its unusual courtship behavior involving interlocking of the venom delivering chelicerae (i.e., the jaws), and several species in the genus are already known to have sexually dimorphic venoms. Here, we use transcriptome and proteome analyses to identify venom components that are dimorphic in Tetragnatha versicolor. We present cDNA sequences including unique, male-specific high molecular weight proteins that have remote, if any, detectable similarity to known venom components in spiders or other venomous lineages and have no detectable homologs in existing databases. While the function of these proteins is not known, their presence in association with the cheliceral locking mechanism during mating together with the presence of prolonged male-male mating attempts in a related, cheliceral-locking species (Doryonychus raptor) lacking the dimorphism suggests potential for a role in sexual communication.

Keywords: Gene families; Proteomics; Sexual communication; Transcriptome; Venom.

Associated data

  • figshare/10.6084/m9.figshare.5378308

Grant support

This work was funded by East Carolina University; the University of California, Berkeley; and Lewis and Clark College. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.