Dataset Information

Toxins from scratch? - Diverse, multimodal gene origins in the predatory robber fly Dasypogon diadema indicate dynamic venom evolution in dipteran insects

ABSTRACT: Venoms and the toxins they contain represent molecular adaptations that have evolved on numerous occasions throughout the animal kingdom. However, the processes that shape venom protein evolution are poorly understood because of the scarcity of whole genome data available for comparative analyses of venomous species. Here, we perform a broad comparative toxicogenomic analysis to gain insight into the genomic mechanisms of venom evolution in robber flies (Asilidae). We first sequenced a high-quality draft genome of the hymenopteran hunting robber fly Dasypogon diadema, and analysed its venom by a combined proteotranscriptomic approach, and compared our results to recently described robber fly venoms to assess the general composition and major components of asilid venom. We then applied a comparative genomics approach, based on one additional asilid genome, ten high-quality dipteran genomes, and two lepidopteran outgroup-genomes, to reveal the evolutionary mechanisms and origins of identified venom proteins in robber flies. While some venom proteins were identified in the non-asilid genomes, several of the identified highly expressed venom proteins appear to be unique to robber flies. Our results reveal that the venom of D. diadema likely evolves in a multimodal fashion comprising 1) neofunctionalization after gene duplication, 2) expression-dependent co-option of proteins and 3) asilid lineage-specific orphan genes with enigmatic origin. The role of such orphan genes is currently being disputed in evolutionary genomics, but has not yet discussed in the context of toxin evolution. Our results display an unexpected dynamic venom evolution in asilid insects, which contrasts the findings of the only other insect toxicogenomic evolutionary analysis, in parasitoid wasps (Hymenoptera), were toxin evolution is dominated by single gene co-option.

INSTRUMENT(S): TripleTOF 5600

ORGANISM(S): Dasypogon Diadema

TISSUE(S): Venom Gland

SUBMITTER: Eivind Undheim

LAB HEAD: Eivind Undheim

PROVIDER: PXD013358 | Pride | 2019-06-13

REPOSITORIES: Pride

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Toxins from scratch? Diverse, multimodal gene origins in the predatory robber fly Dasypogon diadema indicate a dynamic venom evolution in dipteran insects.

Drukewitz Stephan Holger SH Bokelmann Lukas L Undheim Eivind A B EAB von Reumont Björn M BM

GigaScience 20190701 7

<h4>Background</h4>Venoms and the toxins they contain represent molecular adaptations that have evolved on numerous occasions throughout the animal kingdom. However, the processes that shape venom protein evolution are poorly understood because of the scarcity of whole-genome data available for comparative analyses of venomous species.<h4>Results</h4>We performed a broad comparative toxicogenomic analysis to gain insight into the genomic mechanisms of venom evolution in robber flies (Asilidae). ...[more]

PMID: 31289835

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