GEOapplication/xmlftp://ftp.ncbi.nlm.nih.gov/geo/series/GSE330nnn/GSE330818/primary200OKTranscriptomicsRattus norvegicusExpression profiling by high throughput sequencinghttps://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE330818GEOGSEfalseMyelin basic protein is an RNA chaperone in microglial nuclear retro-transportCNS oligodendrocytes generate myelin, an RNA-containing proteolipid substance that enhances axonal transmission. In multiple sclerosis (MS), myelin debris is phagocytosed by microglia (MG), and prior studies have detected myelin-derived mRNA in MG nuclei, suggesting a retrograde transport pathway. We report myelin basic protein (MBP) is a nucleic acid–binding and trafficking protein. We found that retro-transport of myelin RNA into the MG nucleus was phagocytosis and importin-dependent. Transcriptomic and proteomic analyses of MG nuclei revealed enrichment of myelin mRNAs and proteins, with MBP singularly detected in soluble and chromatin-associated fractions. MBP bound mRNA with high affinity (Kd ≈ 0.30 nM) and was sufficient to facilitate MG RNA nuclear import in vitro and in vivo. Functionally, MBP mediated the delivery of small interfering RNAs for targeted knockdown of toll-like receptor 4. These findings indicate MBP as an RNA-binding protein capable of MG nuclear import, providing insight into neuroinflammatory pathology of MS.2026/06/20GSE330818GSM9733172GSM9733171GSM9733170GSM973316925947330818Rattus norvegicus