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Summary: WaspAtlas is a new integrated gene database for the emerging model organismNasonia vitripennis, which combines annotation data from all available annotation releases with original analyses to form the most comprehensiveN. vitripennisresource to date. WaspAtlas allows users to browse and search for gene information in a clear and co-ordinated fashion providing detailed illustrations and easy to understand summaries. The database provides a platform for integrating gene expression and DNA methylation data. WaspAtlas also functions as an archive for empirical data relating to genes, allowing users to easily browse published data relating to their gene(s) of interest. Availability: Freely available on the web at http://waspatlas.com. Website implemented in Catalyst, MySQL and Apache, with all major browsers supported.

The role of epigenetics in the control and evolution of behavior is being increasingly recognized. Here we test whether DNA methylation influences patterns of adaptive sex allocation in the parasitoid wasp Nasonia vitripennis. Female N. vitripennis allocate offspring sex broadly in line with local mate competition (LMC) theory. However, recent theory has highlighted how genomic conflict may influence sex allocation under LMC, conflict that requires parent-of-origin information to be retained by alleles through some form of epigenetic signal. We manipulated whole-genome DNA methylation in N. vitripennis females using the hypomethylating agent 5-aza-2'-deoxycytidine. Across two replicated experiments, we show that disruption of DNA methylation does not ablate the facultative sex allocation response of females, as sex ratios still vary with cofoundress number as in the classical theory. However, sex ratios are generally shifted upward when DNA methylation is disrupted. Our data are consistent with predictions from genomic conflict over sex allocation theory and suggest that sex ratios may be closer to the optimum for maternally inherited alleles

A major question in chronobiology focuses around the “Bünning hypothesis” which implicates the circadian clock in photoperiodic (day-length) measurement and is supported in some systems (e.g. plants) but disputed in others. Here, we used the seasonally-regulated thermotolerance of Drosophila melanogaster to test the role of various clock genes in day-length measurement. In Drosophila, freezing temperatures induce reversible chill coma, a narcosis-like state. We have corroborated previous observations that wild-type flies developing under short photoperiods (winter-like) exhibit significantly shorter chill-coma recovery times (CCRt) than flies that were raised under long (summer-like) photoperiods. Here, we show that arrhythmic mutant strains, per01, tim01 and ClkJrk, as well as variants that speed up or slow down the circadian period, disrupt the photoperiodic component of CCRt. Our results support an underlying circadian function mediating seasonal daylength measurement and indicate that clock genes are tightly involved in photo- and thermo-periodic measurements., Author Summary The circadian clock consists of an extensive genetic network that drives daily rhythms of physiological, biochemical and behavioural processes. The network is evolutionary conserved and has been extensively studied in a broad range of organisms. Another genetic network constitutes the photoperiodic clock and monitors the seasonal change in day-length. Here, we address a major and long-standing question in chronobiology: whether the circadian clock is involved in photoperiodic timing, also known as the Bünning hypothesis. Drosophila, as with many other insects in temperate regions, exhibits a photoperiodic response that allows the insect to anticipate and survive the winter. Here we show that the cold-tolerance of the fly is regulated by the photoperiod. We use this phenotype to test day-length timing in various circadian clock mutants and observe that in null clock mutants, the photoperiodic response is abolished, whereas in mutants that exhibit short or long daily cycles, the photoperiodic response is modified, further supporting a circadian-clock function. Overall, these results provide the first evidence in Drosophila that support for the Bünning hypothesis, and pave the way for the genetic dissection of seasonal timing in Drosophila melanogaster.