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Title: Genome, transcriptome and methylome sequencing of a primitively eusocial wasp reveal a greatly reduced DNA methylation system in a social insect
Abstract

Comparative genomics of social insects has been intensely pursued in recent years with the goal of providing insights into the evolution of social behaviour and its underlying genomic and epigenomic basis. However, the comparative approach has been hampered by a paucity of data on some of the most informative social forms (e.g. incipiently and primitively social) and taxa (especially members of the wasp family Vespidae) for studying social evolution. Here, we provide a draft genome of the primitively eusocial model insectPolistes dominula, accompanied by analysis of caste‐related transcriptome and methylome sequence data for adult queens and workers.Polistes dominulapossesses a fairly typical hymenopteran genome, but shows very low genomewideGCcontent and some evidence of reduced genome size. We found numerous caste‐related differences in gene expression, with evidence that both conserved and novel genes are related to caste differences. Most strikingly, these –omics data reveal a major reduction in one of the major epigenetic mechanisms that has been previously suggested to be important for caste differences in social insects:DNAmethylation. Along with a conspicuous loss of a key gene associated with environmentally responsiveDNAmethylation (the de novoDNAmethyltransferaseDnmt3), these wasps have greatly reduced genomewide methylation to almost zero. In addition to providing a valuable resource for comparative analysis of social insect evolution, our integrative –omics data for this important behavioural and evolutionary model system call into question the general importance ofDNAmethylation in caste differences and evolution in social insects.

 
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NSF-PAR ID:
10015875
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
Molecular Ecology
Volume:
25
Issue:
8
ISSN:
0962-1083
Page Range / eLocation ID:
p. 1769-1784
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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