RNA-seq Analysis of Drosophila melanogaster Heads Harvested 4-Hours Post-PenetratingTraumatic Brain Injury

We are utilizing an adult penetrating traumatic brain injury (PTBI) model in Drosophila to investigate early regenerative mechanisms after damage to the central brain. Here we incorporate RNA-seq analyses to identify candidate pathways that may trigger cell proliferation following PTBI. We find that transcript levels for components of both Toll and Immune Deficiency (Imd) innate immunity pathways are rapidly and highly upregulated post-PTBI. We then tested mutants for the NF-κB transcription factors of the Toll and Imd pathways, Dorsal-related immunity factor (Dif) and Relish (Rel) respectively. Induction of transcripts for antimicrobial peptide (AMP) levels are substantially elevated after PTBI, however their levels revert to near baseline within 24 hours. These results indicate that the innate immunity pathways play an integral role in the regenerative response. Innate immunity previously has been implicated as both a potentiator and an inhibitor of regeneration. Our work suggests that modulation of innate immunity may be essential to prevent adverse outcomes. RNA-Seq analysis from isolated from heads of young male Drosophila melanogaster collected within 6 hrs of eclosion generated by our 'standard cross' = w; UAS-mCD8-GFP;; OK107-GAL4 X yw at four hours after PTBI to both hemispheres of the central brain and from the heads of age- and sex-matched controls without injury. Samples are divided into 3 biological replicas, each from ~100-120 heads. w; UAS-mCD8-GFP;; OK107-GAL4 X yw at four hours after PTBI to both hemispheres of the central brain and from the heads of age- and sex-matched controls without injury. Samples are divided into 3 biological replicas, each from ~100-120 heads.