Project description:Young, or newly evolved, genes arise ubiquitously across the tree of life, and can rapidly acquire novel functions that influence a diverse array of biological processes (Chen et al. 2013)1. Previous work identified a young regulatory gene in Drosophila, Zeus, which diverged rapidly from its parent Caf40 and took on roles in the male reproductive system. This neofunctionalization was accompanied by differential binding of the Zeus protein to loci throughout the Drosophila melanogaster genome Chen et al. 2012)2. However, the way in which new DNA-binding proteins acquire and co-evolve with their targets in the genome is not understood. Here, by comparing Zeus ChIP-seq data from D. melanogaster and D. simulans to the ancestral Caf40 binding events from D. yakuba, a species that diverged before the duplication event, we find a dynamic pattern in which Zeus binding rapidly co-evolved with a previously unknown DNA motif under the influence of positive selection. Interestingly, while both copies of Zeus acquired targets at male-biased and testis-specific genes, D. melanogaster and D. simulans proteins have specialized binding on different chromosomes, a pattern echoed in the evolution of the associated motif. Our results suggest that evolution of young regulatory genes can be coupled to substantial re-wiring of the transcriptional networks into which they integrate, even over short evolutionary timescales. Our results thus uncover dynamic, genome-wide evolutionary processes associated with new genes.
Project description:Cmi (also known as Lpt) is the PHD finger domain-containing subunit of the Drosophila MLR COMPASS (Cmi-Trr) complex. ChIP-seq analysis of Cmi at different stages of Drosophila development suggests dynamic genome localization of the Cmi/MLR complex on enhancers and promoters during Drosophila development.
Project description:We report the evolutionary behaviour of Polycomb group proteins, their recruitment factors and their underlying sequences by performing ChIP-seq analysis in 4-5 different Drosophila species. We demonstrate an extremely high conservation of Polycomb repressive domains across Drosophila species We validate few cases of PRE divergence that shows that cis-driven PRE evolution is a rare event. We further show that PHO recruitment to Polycomb domains is evolutionarily robust to motif changes and that PRC1 stabilizes binding of its key recruiter ChIP-seq analysis of histone marks and chromatin associated factors across 4-5 Drosophila species
Project description:Despite being essential for fertility, genome defence pathway genes often evolve rapidly. However, little is known about the molecular basis of this adaptation. Here, we characterize the evolution of a protein interaction network within the PIWI-interacting small RNA (piRNA) genome defence pathway in Drosophila at unprecedented scale and evolutionary resolution. We uncover pervasive rapid evolution of a protein interaction network anchored at the Heterochromatin Protein 1 (HP1) paralog Rhino. Using complementary phylogenetic analysis, high-throughput yeast-two-hybrid matrix screening, and in vivo interaction analyses in cross-species transgenic flies, we characterized at least three distinct evolutionary protein interaction trajectories across ~40 million years of Drosophila evolution. The comprehensive cross-species interaction data set covering 11 piRNA pathway proteins of five Drosophila species revealed several protein interactions that are fully conserved, indicating functional conservation despite overall rapid amino acid sequence change. Other interactions are preserved through co-evolution and were detected only between proteins in closely related and within species. We also identified sets of species-restricted protein interactions which, through rewiring of a Rhino-anchored transcription factor network, may preserve critical roles in enabling and adapting piRNA production from heterochromatic loci. In sum, our analyses dissected principles of interaction evolution in an adaptively evolving protein-protein interaction network uncovering evolutionary and functional insight into germline piRNA production across Drosophila species. Our work provides key experimental evidence in support of a fundamental model proposing that intermolecular interaction innovation is a major molecular mechanism of evolutionary adaptation in protein-coding genes.
Project description:We identified cis-regulatory elements based on their dynamic chromatin accessibility during the gastrula-larva stages of sea urchin and sea star and studied their evolution in these echinoderm species
Project description:Here we directly test the hypothesis that PCSS results in rapid evolution of the entire male accessory gland proteome and protein networks by taking a system-level approach, combining divergent experimental evolution of PCSS in Drosophila pseudoobscura (Dpse), high resolution mass spectrometry (MS) and proteomic discovery, bioinformatics and population genetic analyses.
2019-02-18 | PXD012545 | Pride
Project description:Dynamic evolution of euchromatic satellites on the X chromosome in Drosophila melanogaster and the simulans clade