Teixeira Costa VenOx25 flash-talk video: Venom composition and venom gland transcriptomics reveal

#Venom composition and venom gland transcriptomics reveal intra- and interspecific variation in the B. neuwiedi complex

Bárbara S Teixeira-Costa1,2, Mônica Colombini2, Juan David Bayona-Serrano3, Ana Maria Moura-da-Silva2, Luciana A Freitas-de-Sousa2, Felipe G Grazziotin1

1Laboratório de Coleções Zoológicas, Instituto Butantan, Avenida Vital Brasil 1500, São Paulo, SP, Brazil

2Laboratório de Imunopatologia, Instituto Butantan, Avenida Vital Brasil 1500, São Paulo, SP, Brazil

3Laboratório de Toxinologia Aplicada, Center of Toxins, Immune-Response and Cell Signaling (CeTICS), Instituto Butantan, Avenida Vital Brasil 1500, São Paulo, SP, Brazil

Snake venoms are complex mixtures of several toxins, whose composition can vary both within and between species. Describing this variability provides opportunities to advance our understanding of organismal evolution and to support effective public health actions. Snakes of the Bothrops neuwiedi complex are currently classified as B. marmoratus and B. neuwiedi. Although their morphology and genetic variation are relatively well studied, the variability in their venoms remains largely unexplored. Here we evaluate variation in venom composition and toxin expression levels across multiple populations of B. marmoratus and B. neuwiedi. We analyzed six specimens of B. neuwiedi from the Brazilian states of Rio de Janeiro, Bahia, and Minas Gerais, and three specimens of B. marmoratus from Minas Gerais and Goiás. We evaluated their venom composition through HPLC and SDS-PAGE. We also evaluated the venom glands through RNA-seq based sequencing. Our results reveal substantial presence of SVMP (snake venom metalloproteinases) in both species, as evidenced by 20 to 100 kDa bands in the SDS-PAGE analysis. Other dominant toxin classes include snake venom serine proteases, PLA2s (phospholipases A2) and C-type lectins. We identified SVMPs as the predominant component in B. neuwiedi venoms. Furthermore, our analysis indicates potential geographic and ontogenetic variation, particularly PLA2 levels. Similarly, SVMPs are the main component in B. marmoratus venoms. Geographic variation in venom compositions was also detected in this species, and our results suggest that B. marmoratus venoms are more diverse than those of B. neuwiedi. Regarding their venom gland transcriptomes, we could confirm the results previously observed for their venom composition. This preliminary study reveals both intra- and interspecific variation in venom composition and transcriptomes among populations of the B. neuwiedi complex, which will be further explored through mass spectrometry analyses.