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Title: Novel Doublesex Duplication Associated with Sexually Dimorphic Development of Dogface Butterfly Wings
Abstract Sexually dimorphic development is responsible for some of the most remarkable phenotypic variation found in nature. Alternative splicing of the transcription factor gene doublesex (dsx) is a highly conserved developmental switch controlling the expression of sex-specific pathways. Here, we leverage sex-specific differences in butterfly wing color pattern to characterize the genetic basis of sexually dimorphic development. We use RNA-seq, immunolocalization, and motif binding site analysis to test specific predictions about the role of dsx in the development of structurally based ultraviolet (UV) wing patterns in Zerene cesonia (Southern Dogface). Unexpectedly, we discover a novel duplication of dsx that shows a sex-specific burst of expression associated with the sexually dimorphic UV coloration. The derived copy consists of a single exon that encodes a DNA binding but no protein-binding domain and has experienced rapid amino-acid divergence. We propose the novel dsx paralog may suppress UV scale differentiation in females, which is supported by an excess of Dsx-binding sites at cytoskeletal and chitin-related genes with sex-biased expression. These findings illustrate the molecular flexibility of the dsx gene in mediating the differentiation of secondary sexual characteristics.  more » « less
Award ID(s):
2108227 1736026
PAR ID:
10289940
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Editor(s):
True, John
Date Published:
Journal Name:
Molecular Biology and Evolution
ISSN:
0737-4038
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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