8I6G

Crystal structure of the African swine fever virus DNA sliding clamp (native form)

Summary for 8I6G

• Entry DOI: 10.2210/pdb8i6g/pdb
• Descriptor: ASFV DNA sliding clamp (2 entities in total)
• Functional Keywords: dna polymerase processivity factor, sliding clamp, dna binding protein
• Biological source: African swine fever virus BA71V
• Total number of polymer chains: 2
• Total formula weight: 72893.47

Authors

Wu, J.,Gong, P. (deposition date: 2023-01-28, release date: 2023-06-07, Last modification date: 2024-05-29)

Primary citation

Wu, J.,Zheng, H.,Gong, P.
Crystal structure of African swine fever virus pE301R reveals a ring-shaped trimeric DNA sliding clamp.
J.Biol.Chem., 299:104872-104872, 2023

PubMed Abstract: African swine fever virus (ASFV) is an important animal pathogen that is causing a current African swine fever pandemic and affecting pork industry globally. ASFV encodes at least 150 proteins, and the functions of many of them remain to be clarified. The ASFV protein E301R (pE301R) was predicted to be a DNA sliding clamp protein homolog working as a DNA replication processivity factor. However, structural evidence was lacking to support the existence of a ring-shaped sliding clamp in large eukaryotic DNA viruses. Here, we have solved a high-resolution crystal structure of pE301R and identified a canonical ring-shaped clamp comprising a pE301R trimer. Interestingly, this complete-toroidal structure is different from those of the monomeric clamp protein homolog, herpes simplex virus UL42, and the C-shaped dimeric human cytomegalovirus UL44, but highly homologous to that of the eukaryotic clamp homolog proliferating cell nuclear antigen. Moreover, pE301R has a unique N-terminal extension that is important in maintaining the trimeric form of the protein in solution, while specific features in length and surface electrostatic potential of its interdomain connector implies specificity in interactions with binding partners such as the viral DNA polymerase. Thus, our data pave the way for further dissection of the processivity clamp protein structural and functional diversity and ASFV DNA replication mechanisms.

PubMed: 37257822
DOI: 10.1016/j.jbc.2023.104872

Experimental method

X-RAY DIFFRACTION (1.79 Å)