ZEBRA (BamHI Z Epstein-Barr virus replication activator, also known as Zta and BZLF1)) is an early lytic protein of EBV encoded by BZLF1. ZEBRA is a homodimer. Each subunit has 245 amino acid residues. It has a basic leucine zipper domain, a characteristic of many transcription factors. ZEBRA binds to the oriLyt (lytic origin of replication) of the EBV genome. It acts as an essential transcriptional regulator that is required for wild-type levels of lytic DNA replication. Binding sites of ZEBRA are at the essential upstream component of oriLyt. It interacts with the viral helicase-primase complex and BMRF1, the viral polymerase accessory factor.