Divergent transcriptional regulation of astrocyte reactivity across disorders [RNA-seq]

RNA sequencing was applied to examine changes in gene expression in reactive astrocytes following traumatic spinal cord injury (SCI) or neuroinflammatory insult by systemic administration of lipopolysaccharide (LPS). Transgenic Ribotag technology was used to isolate astrocyte ribosome-associated mRNAs from the spinal cord of wild type mice and mice with astrocyte-specific conditional gene deletion (cKO) of test-case transcriptional regulators of reactivity, SMARCA4 (Smarca4-astro-cKO) or STAT3 knockout (Stat3-astro-cKO). Examination of differentially expressed gene (DEG) profiles by upstream transcriptional regulator enrichment analysis (TREA) was used identify transcriptional regulators of reactivity in each condition. Together, findings from this study show that transcriptional changes associated with astrocyte reactivity are exquisitely heterogeneous and are customized from vast numbers of potential DEGs via context-specific combinatorial TR interactions. These data have also been made accessible in a open-access, searchable database: http://tr.astrocytereactivity.com Overall design: Astrocyte ribosome-associated mRNAs were isolated from the spinal cord of wild type, Smarca4-astro-cKO, and Stat3-astro-cKO Ribotag mice at 14 days post-SCI or 24 hours following intraperitoneal injection of 5 mg/Kg LPS administration. Equivalent spinal cord tissues were examined from genotype matched healthy (uninjured) control mice.