GSBS Student Publications

Title

Identification of residues important for DNA binding in the full-length human Rad52 protein

UMMS Affiliation

Graduate School of Biomedical Sciences; Department of Biochemistry and Molecular Pharmacology

Date

12-2-2004

Document Type

Article

Medical Subject Headings

Alanine; Amino Acid Sequence; Arginine; Catalysis; Cell Line, Transformed; Chromatography, Gel; Crystallography, X-Ray; *DNA; DNA Damage; DNA Repair; DNA, Single-Stranded; DNA-Binding Proteins; Humans; Models, Molecular; Molecular Sequence Data; Mutagenesis; Mutation; Plasmids; Protein Binding; Protein Structure, Secondary; Protein Structure, Tertiary; Protein-Serine-Threonine Kinases; Rad51 Recombinase; Rad52 DNA Repair and Recombination Protein; Recombination, Genetic; Sequence Homology, Amino Acid

Disciplines

Life Sciences | Medicine and Health Sciences

Abstract

Human Rad52 (HsRad52) is a DNA-binding protein (418 residues) that promotes the catalysis of DNA double strand break repair by the Rad51 recombinase. HsRad52 self-associates to form ring-shaped oligomers as well as higher order complexes of these rings. Analysis of the structural and functional organization of protein domains suggests that many of the determinants of DNA binding lie within the N-terminal 85 residues. Crystal structures of two truncation mutants, HsRad52(1-212) and HsRad52(1-209) support the idea that this region makes up an important part of the DNA binding domain. Here, we report the results of saturating alanine scanning mutagenesis of the N-terminal domain of full-length HsRad52 in which we identify residues that are likely involved in direct contact with single-stranded DNA (ssDNA). Our results largely agree with the position of side-chains seen in the crystal structures but also suggest that certain DNA binding and cross-subunit interactions differ between the 11 subunit ring in the crystal structures of the truncation mutant proteins versus the seven subunit ring formed by full-length HsRad52.

Rights and Permissions

Citation: J Mol Biol. 2005 Jan 14;345(2):239-49. Link to article on publisher's site

Related Resources

Link to article in PubMed

Journal Title

Journal of molecular biology

PubMed ID

15571718