Human Transcription Elongation Factor NELF: Identification of Novel Subunits and Reconstitution of the Functionally Active Complex
Autor: | Masashi Omori, Tomoko Yamada, Hiroshi Handa, Dong-ki Kim, Naoto Inukai, Masaki Endoh, Yuki Yamaguchi, Tadashi Wada, Seiji Sugimoto, Jun Hasegawa, Sittinan Chanarat, Keiichi Yano, Takashi Narita |
---|---|
Rok vydání: | 2003 |
Předmět: |
Saccharomyces cerevisiae Proteins
Positive Transcriptional Elongation Factor B Macromolecular Substances Protein subunit Molecular Sequence Data Peptide Chain Elongation Translational Repressor RNA polymerase II Protein Serine-Threonine Kinases Biology Models Biological Evolution Molecular Structure-Activity Relationship Sequence Analysis Protein Protein Interaction Mapping Humans Amino Acid Sequence Cloning Molecular Nuclear protein Negative elongation factor Molecular Biology Transcription factor Transcriptional Regulation Genetics Nuclear Proteins Cell Biology DSIF Repressor Proteins Protein Subunits biology.protein RNA Polymerase II Transcriptional Elongation Factors Transcription Factors |
Zdroj: | Molecular and Cellular Biology. 23:1863-1873 |
ISSN: | 1098-5549 |
DOI: | 10.1128/mcb.23.6.1863-1873.2003 |
Popis: | The multisubunit transcription elongation factor NELF (for negative elongation factor) acts together with DRB (5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole) sensitivity-inducing factor (DSIF)/human Spt4-Spt5 to cause transcriptional pausing of RNA polymerase II (RNAPII). NELF activity is associated with five polypeptides, A to E. NELF-A has sequence similarity to hepatitis delta antigen (HDAg), the viral protein that binds to and activates RNAPII, whereas NELF-E is an RNA-binding protein whose RNA-binding activity is critical for NELF function. To understand the interactions of DSIF, NELF, and RNAPII at a molecular level, we identified the B, C, and D proteins of human NELF. NELF-B is identical to COBRA1, recently reported to associate with the product of breast cancer susceptibility gene BRCA1. NELF-C and NELF-D are highly related or identical to the protein called TH1, of unknown function. NELF-B and NELF-C or NELF-D are integral subunits that bring NELF-A and NELF-E together, and coexpression of these four proteins in insect cells resulted in the reconstitution of functionally active NELF. Detailed analyses using mutated recombinant complexes indicated that the small region of NELF-A with similarity to HDAg is critical for RNAPII binding and for transcriptional pausing. This study defines several important protein-protein interactions and opens the way for understanding the mechanism of DSIF- and NELF-induced transcriptional pausing. |
Databáze: | OpenAIRE |
Externí odkaz: |