- 作者: Mario Coemente Estable Martin Hirst Brendan Bell Michael V. O'Shaughnessy Ivan Sadowski
- 作者服務機構: Department of biochemistry and Molecular Biology, Faculty of Medicine, University of British Columbia, and B.C. Center for Excellence in HIV/AIDS, St. Paul's Hospital, Vancouver, B.C., Canada
- 中文摘要: --
- 英文摘要: The combination of high turnover and error-prone re-verse transcription results in naturally occurring humanimmunodeficiency virus-1 long terminal repeats that dif-fer considerably from the prototype sequencem Althoughno transcription-factor-binding site escapes mutation,the only mutated site that appears to be invariably com-pensated by co-occurrence of its duplication is the RBE IIIsite, a target for the transcription factor RBF-2. In thiswork, we characterize RBF-2 further by biochemical puri-fication. RBF-2 was purified by chromatography on hep-arin agarose and Mono-Q ion exchange chromatogra-phy, followed by affinity chromatography on mutant andwild-type RBE III oligonucleotide columns. The purifiedRBF-2 preparation contained 4 major and 1 minor poly-peptides of 50, 100, 110, 120 and 125 kD, as detected bysilver staining in SDS-PAGE gels. UV cross-linking re-vealed a specific 100-kD species, indicating that this pro-tein likely represents the DNA-binding component of acomplex. A second factor with DNA-binding specificitysimilar to that of RBF-2, called RBF-B, was also identifiedby heparin-agarose fractionation, which suggests thateffects of the RBE III cis-element may be mediated by acombination of factors in vivo.
- 中文關鍵字: --
- 英文關鍵字: RBF-2 Purification. HIV-1 LTR. Transcription factor