One of two Epstein-Barr virus nuclear antigens contains a glycine-alanine copolymer domain.

Abstract

A gene fusion between an Epstein-Barr virus (EBV) triplet nucleotide repeat array (IR3), which has homology to host DNA, and lacZ was used to demonstrate that this EBV sequence encodes part of the Epstein-Barr nuclear antigen (EBNA). The IR3 sequence is translated into a glycine-alanine copolymer that reacts with anti-EBNA human sera. Some EBV-immune human antisera recognize a 2nd intranuclear protein that is also specific for latently infected human lymphoblastoid cells, and is designated EBNA2. EBNA2 is not related to EBNA1 because the MW of EBNA2 is 82 kilodaltons; that of EBNA1 varies from 68 to 85 kilodaltons among cells transformed by different EBV isolates, and EBNA2 does not contain the copolymer domain of EBNA1.