title: RNA-binding protein QKI regulates Glial fibrillary acidic protein expression in human astrocytes.
abstract: Linkage, association and expression studies previously pointed to the human QKI, KH domain containing, RNA-binding (QKI) as a candidate gene for schizophrenia. Functional studies of the mouse orthologue Qk focused mainly on its role in oligodendrocyte development and myelination, while its function in astroglia remained unexplored. Here, we show that QKI is highly expressed in human primary astrocytes and that its splice forms encode proteins targeting different subcellular localizations. Uncovering the role of QKI in astrocytes is of interest in light of growing evidence implicating astrocyte dysfunction in the pathogenesis of several disorders of the central nervous system. We selectively silenced QKI splice variants in human primary astrocytes and used RNA sequencing to identify differential expression and splice variant composition at the genome-wide level. We found that an mRNA expression of Glial fibrillary acidic protein (GFAP), encoding a major component of astrocyte intermediate filaments, was down-regulated after QKI7 splice variant silencing. Moreover, we identified a potential QKI-binding site within the 3' untranslated region of human GFAP. This sequence was not conserved between mice and humans, raising the possibility that GFAP is a target for QKI in humans but not rodents. Haloperidol treatment of primary astrocytes resulted in coordinated increases in QKI7 and GFAP expression. Taken together, our results provide the first link between QKI and GFAP, two genes with alterations previously observed independently in schizophrenic patients. Our findings for QKI, together with its well-known role in myelination, suggest that QKI is a hub regulator of glia function in humans.
authors: Department of Evolution and Development, Evolutionary Biology Centre, Uppsala University, Uppsala,Sweden.
authors: Katarzyna J
authors: KJ
authors: Radomska
authors: Jonatan
authors: J
authors: Halvardson
authors: Björn
authors: B
authors: Reinius
authors: Eva
authors: E
authors: Lindholm Carlström
authors: Lina
authors: L
authors: Emilsson
authors: Lars
authors: L
authors: Feuk
authors: Elena
authors: E
authors: Jazin
mesh_terms: D000595:Amino Acid Sequence; D014150:Antipsychotic Agents / Q000494:pharmacology; D001253:Astrocytes / Q000378:metabolism*; D002478:Cells, Cultured; D015870:Gene Expression / Q000187:drug effects; D005786:Gene Expression Regulation; D055785:Gene Knockdown Techniques; D005904:Glial Fibrillary Acidic Protein / Q000235:genetics* / Q000378:metabolism; D006220:Haloperidol / Q000494:pharmacology; D006801:Humans; D008969:Molecular Sequence Data; D061251:Primary Cell Culture; D054730:Protein Interaction Domains and Motifs; D020033:Protein Isoforms / Q000502:physiology; D021381:Protein Transport; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000502:physiology*; D012559:Schizophrenia / Q000378:metabolism; D017423:Sequence Analysis, RNA; D059467:Transcriptome
chemical_list: D014150:Antipsychotic Agents; D005904:Glial Fibrillary Acidic Protein; D020033:Protein Isoforms; C490832:QKI protein, human; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D016601:RNA-Binding Proteins; D006220:Haloperidol