Venom Profiling of a Population of the Theraphosid Spider Phlogius crassipes Reveals Continuous Ontogenetic Changes from Juveniles through Adulthood

Abstract

Theraphosid spiders (tarantulas) are venomous arthropods found in most tropical and subtropical regions of the world. Tarantula venoms are a complex cocktail of toxins with potential use as pharmacological tools, drugs and bioinsecticides. Although numerous toxins have been isolated from tarantula venoms, little research has been carried out on the venom of Australian tarantulas. We therefore investigated the venom profile of the Australian theraphosid spider Phlogius crassipes and examined whether there are ontogenetic changes in venom composition. Spiders were divided into four ontogenic groups according to cephalothorax length, then the venom composition of each group was examined using gel electrophoresis and mass spectrometry. We found that the venom of P. crassipes changes continuously during development and throughout adulthood. Our data highlight the need to investigate the venom of organisms over the course of their lives to uncover and understand the changing functions of venom and the full range of toxins expressed. This in turn should lead to a deeper understanding of the organism’s ecology and enhance the potential for biodiscovery.

Tarantulas of Australia: phylogenetics and venomics

“…Visual comparison of chromatograms has been used in a range of different projects (e.g. Escoubas et al, 2002;Santana et al, 2017). This technique has the advantage of being cheap, fast and even untrained people can visually compare chromatograms.…”

“…The presence and absence of peaks on chromatograms can be observed between phylogenetic groups but individual variation of peak intensity has been evident in most groups. The individual variation can be related to sex, maturity, location and phylogeny (Escoubas et al, 2006;Herzig, 2010;Santana et al, 2017).…”

“…Furthermore, Santana et al (2017) determined that the components evident within the venom of Australian tarantulas changes ontogenetically. Most spiders collected in our study were females, but some males or sub-adults were also used.…”

“…Diverse factors can influence the presence of these different components within spider venom (Escoubas et al, 2006;Herzig, 2010;Santana et al, 2017). These include sex, maturity, location and phylogeny (Escoubas, Célérier, & Nakajima, 1997;Herzig, 2010;Herzig & Hodgson, 2009;Santana et al, 2017).…”

“…Diverse factors can influence the presence of these different components within spider venom (Escoubas et al, 2006;Herzig, 2010;Santana et al, 2017). These include sex, maturity, location and phylogeny (Escoubas, Célérier, & Nakajima, 1997;Herzig, 2010;Herzig & Hodgson, 2009;Santana et al, 2017). Two studies led by Escoubas (Escoubas et al, 1997;Escoubas, Corzo, Whiteley, Célérier, & Nakajima, 2002) have reported possible identification of species using venom.…”