3JA9

Structure of native human PCNA

Summary for 3JA9

• Entry DOI: 10.2210/pdb3ja9/pdb
• EMDB information: 6339
• Descriptor: Proliferating cell nuclear antigen (2 entities in total)
• Functional Keywords: dna, replication, processivity, oncogene, dna-binding systemic lupus erythematosus, dna binding protein
• Biological source: Homo sapiens (human)
• Total number of polymer chains: 3
• Total formula weight: 86387.26

Authors

Lau, W.C.Y.,Li, Y.,Zhang, Q.,Huen, M.S.Y. (deposition date: 2015-05-19, release date: 2015-12-09, Last modification date: 2024-10-16)

Primary citation

Lau, W.C.,Li, Y.,Zhang, Q.,Huen, M.S.
Molecular architecture of the Ub-PCNA/Pol eta complex bound to DNA
Sci Rep, 5:15759-15759, 2015

PubMed Abstract: Translesion synthesis (TLS) is the mechanism by which DNA polymerases replicate through unrepaired DNA lesions. TLS is activated by monoubiquitination of the homotrimeric proliferating cell nuclear antigen (PCNA) at lysine-164, followed by the switch from replicative to specialized polymerases at DNA damage sites. Pol η belongs to the Y-Family of specialized polymerases that can efficiently bypass UV-induced lesions. Like other members of the Y-Family polymerases, its recruitment to the damaged sites is mediated by the interaction with monoubiquitinated PCNA (Ub-PCNA) via its ubiquitin-binding domain and non-canonical PCNA-interacting motif in the C-terminal region. The structural determinants underlying the direct recognition of Ub-PCNA by Pol η, or Y-Family polymerases in general, remain largely unknown. Here we report a structure of the Ub-PCNA/Pol η complex bound to DNA determined by single-particle electron microscopy (EM). The overall obtained structure resembles that of the editing PCNA/PolB complex. Analysis of the map revealed the conformation of ubiquitin that binds the C-terminal domain of Pol η. Our present study suggests that the Ub-PCNA/Pol η interaction requires the formation of a structured binding interface, which is dictated by the inherent flexibility of Ub-PCNA.

PubMed: 26503230
DOI: 10.1038/srep15759

Experimental method

ELECTRON MICROSCOPY (22 Å)