CSB Is a Component of RNA Pol I Transcription

• Published in: Molecular cell Vol. 10; no. 4; pp. 819 - 829
• Main Authors: Bradsher, John, Auriol, Jerome, de Santis, Luca Proietti, Iben, Sebastian, Vonesch, Jean-Luc, Grummt, Ingrid, Egly, Jean-Marc
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.10.2002; Cell Press
• Subjects: Biochemistry, Molecular Biology; Blotting, Western; Cell Nucleolus - metabolism; Cells, Cultured; DNA Helicases - deficiency; DNA Helicases - genetics; DNA Helicases - metabolism; DNA Repair Enzymes; DNA-Binding Proteins - genetics; DNA-Binding Proteins - metabolism; Endonucleases; Fibroblasts; Fluorescent Antibody Technique; Humans; Life Sciences; Multienzyme Complexes - chemistry; Multienzyme Complexes - metabolism; Mutation; Nuclear Proteins; Poly-ADP-Ribose Binding Proteins; Protein Binding; Proteins - genetics; Proteins - metabolism; RNA Polymerase I - metabolism; RNA, Ribosomal - biosynthesis; Transcription Factor TFIIH; Transcription Factors; Transcription Factors, TFII - metabolism; Transcription, Genetic; Xeroderma Pigmentosum Group D Protein
• ISSN: 1097-2765; 1097-4164
• DOI: 10.1016/S1097-2765(02)00678-0

Mutation in the CSB gene results in the human Cockayne's syndrome (CS). Here, we provide evidence that CSB is found not only in the nucleoplasm but also in the nucleolus within a complex (CSB IP/150) that contains RNA pol I, TFIIH, and XPG and promotes efficient rRNA synthesis. CSB is active in in vitro RNA pol I transcription and restores rRNA synthesis when transfected in CSB-deficient cells. We also show that mutations in CSB, as well as in XPB and XPD genes, all of which confer CS, disturb the RNA pol I/TFIIH interaction within the CSB IP/150. In addition to revealing an unanticipated function for CSB in rRNA synthesis, we show that the fragility of this complex could be one factor contributing to the CS phenotype.