title: FUS is sequestered in nuclear aggregates in ALS patient fibroblasts.
abstract: Mutations in the RNA-binding protein FUS have been shown to cause the neurodegenerative disease amyotrophic lateral sclerosis (ALS). We investigate whether mutant FUS protein in ALS patient-derived fibroblasts affects normal FUS functions in the nucleus. We investigated fibroblasts from two ALS patients possessing different FUS mutations and a normal control. Fibroblasts from these patients have their nuclear FUS protein trapped in SDS-resistant aggregates. Genome-wide analysis reveals an inappropriate accumulation of Ser-2 phosphorylation on RNA polymerase II (RNA Pol II) near the transcription start sites of 625 genes for ALS patient cells and after small interfering RNA (siRNA) knockdown of FUS in normal fibroblasts. Furthermore, both the presence of mutant FUS protein and siRNA knockdown of wild-type FUS correlate with altered distribution of RNA Pol II within fibroblast nuclei. A loss of FUS function in orchestrating Ser-2 phosphorylation of the CTD of RNA Pol II is detectable in ALS patient-derived fibroblasts expressing mutant FUS protein, even when the FUS protein remains largely nuclear. A likely explanation for this loss of function is the aggregation of FUS protein in nuclei. Thus our results suggest a specific mechanism by which mutant FUS can have biological consequences other than by the formation of cytoplasmic aggregates.
authors.affiliation: Howard Hughes Medical Institute, Department of Chemistry and Biochemistry and BioFrontiers Institute, University of Colorado, Boulder, CO 80309.
authors.forename: Jacob C
authors.initials: JC
authors.lastname: Schwartz
authors.affiliation: Howard Hughes Medical Institute, Department of Chemistry and Biochemistry and BioFrontiers Institute, University of Colorado, Boulder, CO 80309.
authors.forename: Elaine R
authors.initials: ER
authors.lastname: Podell
authors.affiliation: Department of Neurology, Massachusetts General Hospital, Boston, MA 02114 Howard Hughes Medical Institute, Harvard Stem Cell Institute and Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138.
authors.forename: Steve S W
authors.initials: SS
authors.lastname: Han
authors.affiliation: Department of Neurology, Massachusetts General Hospital, Boston, MA 02114.
authors.forename: James D
authors.initials: JD
authors.lastname: Berry
authors.affiliation: Howard Hughes Medical Institute, Harvard Stem Cell Institute and Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138.
authors.forename: Kevin C
authors.initials: KC
authors.lastname: Eggan
authors.affiliation: Howard Hughes Medical Institute, Department of Chemistry and Biochemistry and BioFrontiers Institute, University of Colorado, Boulder, CO 80309 thomas.cech@colorado.edu.
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Cech
mesh_terms: D000690:Amyotrophic Lateral Sclerosis / Q000235:genetics / Q000378:metabolism*; D002467:Cell Nucleus / Q000378:metabolism*; D002478:Cells, Cultured; D005347:Fibroblasts / Q000378:metabolism; D006801:Humans; D010766:Phosphorylation; D066329:Protein Aggregates; D034622:RNA Interference; D012319:RNA Polymerase II / Q000378:metabolism; D034702:RNA-Binding Protein FUS / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D024363:Transcription Initiation Site
chemical_list: D066329:Protein Aggregates; D034702:RNA-Binding Protein FUS; D012319:RNA Polymerase II