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The jewel wasp Nasonia vitripennis is a rising model organism for the study of haplo-diploid reproduction characteristic of hymenopteran insects, which include all wasps, bees, and ants. We performed transcriptional profiling of the ovary, the female soma, and the male soma of N. vitripennis to complement a previously existing transcriptome of the wasp testis. These data were deposited into an open-access genome browser for visualization of transcripts relative to their gene models. We used these data to identify the assemblies of genes uniquely expressed in the germ-line tissues. We found that 156 protein-coding genes are expressed exclusively in the wasp testis compared with only 22 in the ovary. Of the testis-specific genes, eight are candidates for male-specific DNA packaging proteins known as protamines. We found very similar expression patterns of centrosome associated genes in the testis and ovary, arguing that de novo centrosome formation, a key process for development of unfertilized eggs into males, likely does not rely on large-scale transcriptional differences between these tissues. In contrast, a number of meiosis-related genes show a bias toward testis-specific expression, despite the lack of true meiosis in N. vitripennis males. These patterns may reflect an unexpected complexity of male gamete production in the haploid males of this organism. Broadly, these data add to the growing number of genomic and genetic tools available in N. vitripennis for addressing important biological questions in this rising insect model organism.

The heterochromatin protein 1 (HP1) gene family includes a set of paralogs in higher eukaryotes that serve fundamental roles in heterochromatin structure and maintenance, and other chromatin-related functions. At least 10 full and 16 partial HP1 genes exist among Drosophila species, with multiple gene gains, losses, and sub-functionalizations within this insect group. An important question is whether this diverse set of HP1 genes and their dynamic evolution represent the standard rule in eukaryotic groups. Here we have begun to address this question by bio-informatically identifying the HP1 family genes in representative species of the insect order Hymenoptera, which includes all ants, bees, wasps, and sawflies. Compared to Drosophila species, Hymenopterans have a much simpler set of HP1 genes, including one full and two partial HP1s. All 3 genes appear to have been present in the common ancestor of the Hymenopterans and they derive from a Drosophila HP1B-like gene. In ants, a partial HP1 gene containing only a chromoshadow domain harbors amino acid changes at highly conserved sites within the PxVxL recognition region, suggesting that this gene has undergone sub-functionalization. In the jewel wasp Nasonia vitripennis, the full HP1 and partial chromoshadow-only HP1 are expressed in both germ line and somatic tissues. However, the partial chromodomain-only HP1 is expressed exclusively in the ovary and testis, suggesting that it may have a specialized chromatin role during gametogenesis. Our findings demonstrate that the HP1 gene family is much simpler and evolutionarily less dynamic within the Hymenopterans compared to the much younger Drosophila group, a pattern that may reflect major differences in the range of chromatin-related functions present in these and perhaps other insect groups.