Let's talk about sex; Sexual dimorphism in immature development and gene expression in Chrysomya rufifacies (Diptera: Calliphoridae)

Sexual dimorphism in global gene expression is not well characterized in immature insects, as research in this area (especially in larval holometabolous insects) relies upon mutants or known genetic markers and individual extractions. The hairy maggot blow fly, Chrysomya rufifacies, exhibits a mongenic sex-determination mechanism in which females have all-male or all-female offspring clutches. Therefore, it is possible to leverage this unusual sex determination mechanism to the study sexual dimirphism in gene expression in wild-type immmature stages. Using a combination of RNAseq/ de novo transcriptomics and whole-organism work, it was shown this species exhibits sexual dimorphism in development time and gene expression. Gene expression was male-biased, except in the egg stage. In the larval stage, major differences were exhibited in expression of genes associated with muscular and neurological differentiation.  Most of the gene expression dimorphism in the pupal stage was related to gamteogenesis and germ tissue development. The impact of this work in medical and veterinary entomology, developmental biology, and forensic entomology will be discussed.