1QUQ

COMPLEX OF REPLICATION PROTEIN A SUBUNITS RPA14 AND RPA32

Summary for 1QUQ

• Entry DOI: 10.2210/pdb1quq/pdb
• Descriptor: PROTEIN (REPLICATION PROTEIN A 32 KD SUBUNIT), PROTEIN (REPLICATION PROTEIN A 14 KD SUBUNIT) (3 entities in total)
• Functional Keywords: rpa, ob-fold, ssdna-binding, dna-binding protein, dna binding protein
• Biological source: Homo sapiens (human); More
• Cellular location: Nucleus : P15927 P35244
• Total number of polymer chains: 4
• Total formula weight: 56032.61

Authors

Bochkarev, A.,Bochkareva, E.,Frappier, L.,Edwards, A.M. (deposition date: 1999-07-02, release date: 1999-08-13, Last modification date: 2024-02-14)

Primary citation

Bochkarev, A.,Bochkareva, E.,Frappier, L.,Edwards, A.M.
The crystal structure of the complex of replication protein A subunits RPA32 and RPA14 reveals a mechanism for single-stranded DNA binding.
EMBO J., 18:4498-4504, 1999

PubMed Abstract: Replication protein A (RPA), the eukaryote single-stranded DNA-binding protein (SSB), is a heterotrimer. The largest subunit, RPA70, which harbours the major DNA-binding activity, has two DNA-binding domains that each adopt an OB-fold. The complex of the two smaller subunits, RPA32 and RPA14, has weak DNA-binding activity but the mechanism of DNA binding is unknown. We have determined the crystal structure of the proteolytic core of RPA32 and RPA14, which consists of the central two-thirds of RPA32 and the entire RPA14 subunit. The structure revealed that RPA14 and the central part of RPA32 are structural homologues. Each subunit contains a central OB-fold domain, which also resembles the DNA-binding domains in RPA70; an N-terminal extension that interacts with the central OB-fold domain; and a C-terminal helix that mediate heterodimerization via a helix-helix interaction. The OB-fold of RPA32, but not RPA14, possesses additional similarity to the RPA70 DNA-binding domains, supporting a DNA-binding role for RPA32. The discovery of a third and fourth OB-fold in RPA suggests that the quaternary structure of SSBs, which in Bacteria and Archaea are also tetramers of OB-folds, is conserved in evolution. The structure also suggests a mechanism for RPA trimer formation.

PubMed: 10449415
DOI: 10.1093/emboj/18.16.4498

Experimental method

X-RAY DIFFRACTION (2.5 Å)