title: Characterization of the minimal DNA-binding domain of the HIV integrase protein.
abstract: The human immunodeficiency virus (HIV) integrase (IN) protein mediates an essential step in the retroviral lifecycle, the integration of viral DNA into human DNA. A DNA-binding domain of HIV IN has previously been identified in the C-terminal part of the protein. We tested truncated proteins of the C-terminal region of HIV-1 IN for DNA binding activity in two different assays: UV-crosslinking and southwestern blot analysis. We found that a polypeptide fragment of 50 amino acids (IN220-270) is sufficient for DNA binding. In contrast to full-length IN protein, this domain is soluble under low salt conditions. DNA binding of IN220-270 to both viral DNA and non-specific DNA occurs in an ion-independent fashion. Point mutations were introduced in 10 different amino acid residues of the DNA-binding domain of HIV-2 IN. Mutation of basic amino acid K264 results in strong reduction of DNA binding and of integrase activity.
authors.affiliation: Division of Molecular Biology, Netherlands Cancer Institute, Amsterdam.
authors.forename: R A
authors.initials: RA
authors.lastname: Lutzke
authors.forename: C
authors.initials: C
authors.lastname: Vink
authors.forename: R H
authors.initials: RH
authors.lastname: Plasterk
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D001665:Binding Sites; D015139:Blotting, Southern; D015153:Blotting, Western; D003432:Cross-Linking Reagents; D004254:DNA Nucleotidyltransferases / Q000737:chemistry* / Q000378:metabolism*; D004279:DNA, Viral / Q000737:chemistry* / Q000378:metabolism*; D015497:HIV-1 / Q000201:enzymology*; D019426:Integrases; D008274:Magnesium / Q000494:pharmacology; D008345:Manganese / Q000494:pharmacology; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D017354:Point Mutation; D016415:Sequence Alignment; D014466:Ultraviolet Rays
chemical_list: D003432:Cross-Linking Reagents; D004279:DNA, Viral; D008345:Manganese; D004254:DNA Nucleotidyltransferases; D019426:Integrases; D008274:Magnesium