1ci4
From Proteopedia
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THE CRYSTAL STRUCTURE OF HUMAN BARRIER-TO-AUTOINTEGRATION FACTOR (BAF)
Contents |
Overview
Barrier-to-autointegration factor (BAF) is a host cell protein that plays, a crucial role in retroviral integration. Preintegration complexes (PICs), stripped of BAF lose their normal integration activity, which can be, restored by incubation with purified BAF. BAF bridges double-stranded DNA, both intra- and intermolecularly in a non-sequence-specific manner, leading to the formation of a nucleoprotein network. BAF also binds to the, nuclear protein lamina-associated polypeptide 2 (LAP2), and is localized, with chromatin during interphase and mitosis. The crystal structure of, homodimeric human BAF has been determined to 1.9 A resolution. The fold of, the BAF monomer resembles that of the second domain of RuvA. This, comparison revealed the presence of the helix-hairpin-helix (HhH), nonspecific DNA binding motif within BAF. A novel feature of BAF's HhH, motif is the occupation of the metal binding site by the epsilon-amino, group of Lys 6, providing an alternative means of sequestering positive, charge. Mutational analysis corroborates the HhH motif's prominent role in, DNA binding and argues against a previously proposed helix-turn-helix, (HTH) binding site located in another region of the monomer. A model of, BAF bridging DNA via the HhH motif is proposed.
Disease
Known disease associated with this structure: Epilepsy, myoclonic, benign adult familial OMIM:[601068]
About this Structure
1CI4 is a Single protein structure of sequence from Homo sapiens. Full crystallographic information is available from OCA.
Reference
Structural basis of DNA bridging by barrier-to-autointegration factor., Umland TC, Wei SQ, Craigie R, Davies DR, Biochemistry. 2000 Aug 8;39(31):9130-8. PMID:10924106
Page seeded by OCA on Mon Nov 12 16:21:51 2007
