Sequence-specific DNA binding of the Epstein-Barr virus nuclear antigen (EBNA-1) to clustered sites in the plasmid maintenance region

摘要: Latently infected B lymphocytes continuously express an Epstein-Barr Virus nuclear antigen (EBNA-1) required in trans for maintenance of the plasmid state EBV genome. Filter binding assays and DNAase I footprinting analyses revealed that carboxy-terminal domain EBNA-1 protects sites at three different loci 172,000 bp Two these correspond to essential elements within 1800 segment defined as minimal region (ori-P). Binding each 20 X 30 tandem repeats "sink" locus 25 centered over a 12 palindromic consensus sequence TAGCATATGCTA. The nearby dyad symmetry "origin" contains two 46 protected regions encompassing paired core sites. demonstration sequence-specific multiple suggests has pleiotropic functions, which may include control copy number segregation plasmids well initiation replication.