Journal
BMC GENOMICS
Volume 21, Issue 1, Pages -Publisher
BMC
DOI: 10.1186/s12864-020-6545-9
Keywords
Modularity; Venom; Gene family evolution; Transcriptomics; Bothriechis
Funding
- National Science Foundation [DUE 1161228, DEB 1638879, DEB 1822417, DEB 1638902]
- Southwestern Association of Naturalists McCarley Research Grant
- Theodore Roosevelt Memorial Fund through the American Museum of Natural History
- Explorers Club Exploration Fund
- Explorers Club Mamont Scholars program
Ask authors/readers for more resources
Background Modularity is the tendency for systems to organize into semi-independent units and can be a key to the evolution and diversification of complex biological systems. Snake venoms are highly variable modular systems that exhibit extreme diversification even across very short time scales. One well-studied venom phenotype dichotomy is a trade-off between neurotoxicity versus hemotoxicity that occurs through the high expression of a heterodimeric neurotoxic phospholipase A(2) (PLA(2)) or snake venom metalloproteinases (SVMPs). We tested whether the variation in these venom phenotypes could occur via variation in regulatory sub-modules through comparative venom gland transcriptomics of representative Black-Speckled Palm-Pitvipers (Bothriechis nigroviridis) and Talamancan Palm-Pitvipers (B. nubestris). Results We assembled 1517 coding sequences, including 43 toxins for B. nigroviridis and 1787 coding sequences including 42 toxins for B. nubestris. The venom gland transcriptomes were extremely divergent between these two species with one B. nigroviridis exhibiting a primarily neurotoxic pattern of expression, both B. nubestris expressing primarily hemorrhagic toxins, and a second B. nigroviridis exhibiting a mixed expression phenotype. Weighted gene coexpression analyses identified six submodules of transcript expression variation, one of which was highly associated with SVMPs and a second which contained both subunits of the neurotoxic PLA(2) complex. The sub-module association of these toxins suggest common regulatory pathways underlie the variation in their expression and is consistent with known patterns of inheritance of similar haplotypes in other species. We also find evidence that module associated toxin families show fewer gene duplications and transcript losses between species, but module association did not appear to affect sequence diversification. Conclusion Sub-modular regulation of expression likely contributes to the diversification of venom phenotypes within and among species and underscores the role of modularity in facilitating rapid evolution of complex traits.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available