Autor: |
Shah, W A, Ambinder, R F, Hayward, G S, Hayward, S D |
Zdroj: |
The Journal of Virology; June 1992, Vol. 66 Issue: 6 p3355-3362, 8p |
Abstrakt: |
The Epstein-Barr virus nuclear antigen EBNA-1 is essential for replication of the viral DNA during latency. EBNA-1 binds as a dimer to palindromic recognition sequences within the plasmid origin of replication, ori-P. In this study, proteinase K susceptibility has been used to further characterize the DNA-binding domain of EBNA-1. Limited protease digestion of EBNA-1 (amino acids 408 to 641) generated a smaller DNA-binding species that had a degree of inherent protease resistance. When EBNA-1 was preincubated with a specific DNA probe, the protease resistance of the smaller binding species increased 100-fold, suggesting that the conformation of EBNA-1 changes on binding. The protease-resistant species comprised an 18-kDa polypeptide that was further cleaved at high levels of protease to 11- and 5.4-kDa products. A model of the proposed protease-resistant domain structure is presented. Constructions carrying serial, internal deletions across the 18-kDa domain were created. Each of the deletions perturbed dimerization ability and abolished DNA binding. These studies suggest that the DNA-binding and dimerization motifs of EBNA-1 lie within a conformationally discrete domain whose overall integrity is necessary for EBNA-1-DNA interaction. |
Databáze: |
Supplemental Index |
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