Qualitative and Quantitative Proteomic Analysis of Venoms from Mexican Rattlesnakes

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  Qualitative and Quantitative Proteomic Analysis of Venoms from Mexican Rattlesnakes Abstract Despite the vast biodiversity of Mexican vipers, venom of endemic species has been barely studied. Here we analyzed the venom composition of three endemic species of rattlesnakes: Crotalus aquilus , C. triseriatus , and C. ravus . We used quantitative chromato-mass-spectrometry and compared venoms with C. molossus , a species commonly found in North America, in a comparative and phylogenetic framework. In total, we identified 165 proteins grouped in 19 main protein families, consistent with previous reports for viperid venoms. In C. aquilus and C. triseriatus , the most predominant protein-family type was Serine Proteases, and in C. triseriatus and C. molossus it was Snake Venom Metalloproteases. The Label-free quantification revealed a high proportion of Snake Venom Metalloproteases in C. aquilus , C. triseriatus , and C. molossus , reaching 28–47% of the total venom. In contrast, in ...

Spider silk tensile performance does not correlate with web use

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Spider silk tensile performance does not correlate with web use

Abstract

Spider silk is amongst the toughest materials produced by living systems, but its tensile performance varies considerably between species. Despite the extensive sampling of the material properties and composition of dragline silk, the understanding why some silks perform better than others is still limited. Here, I adopted a phylogenetic comparative approach to re-analyse structural and mechanical data from the Silkome database and the literature across 164 species to (a) provide an extended model of silk property evolution, (b) test for correlations between structural and mechanical properties, and (c) to test if silk tensile performance differs between web-building and non-web-building species. Unlike the common notion that orb-weavers have evolved the best performing silks, outstanding tensile properties were found both in and outside the araneoid clade. Phylogenetic linear models indicated that the mechanical and structural properties of spider draglines poorly correlate, but silk strength and toughness correlated better with birefringence (an indicator of the material anisotropy) than crystallinity. Furthermore, in contrast to previous ideas, silk tensile performance did not differ between ecological guilds. These findings indicate multiple unknown pathways towards the evolution of spider silk tensile super-performance, calling for a better integration of non-orb-weaving spiders in spider silk studies.


Jonas O Wolff, Spider silk tensile performance does not correlate with web use, Evolution, 2024;, qpae135, https://doi.org/10.1093/evolut/qpae135