''BZLF1'' (BamHI Z fragment leftward

open reading frame In molecular biology, open reading frames (ORFs) are defined as spans of DNA sequence between the start and stop codons. Usually, this is considered within a studied region of a prokaryotic DNA sequence, where only one of the six possible readin ...

1), also known as ''Zta'', ''EB1,'' is an immediate-early viral gene of the

Epstein–Barr virus The Epstein–Barr virus (EBV), formally called ''Human gammaherpesvirus 4'', is one of the nine known human herpesvirus types in the herpes family, and is one of the most common viruses in humans. EBV is a double-stranded DNA virus. It is b ...

(EBV) of the Herpes Virus Family, which induces cancers and infects primarily the

B-cells B cells, also known as B lymphocytes, are a type of white blood cell of the lymphocyte subtype. They function in the humoral immunity component of the adaptive immune system. B cells produce antibody molecules which may be either secreted or ...

of 95% of the human population. This gene (along with others) produces the expression of other EBV genes in other stages of disease progression, and is involved in converting the virus from the latent to the

lytic The lytic cycle ( ) is one of the two cycles of viral reproduction (referring to bacterial viruses or bacteriophages), the other being the lysogenic cycle. The lytic cycle results in the destruction of the infected cell and its membrane. Bacteri ...

form.

ZEBRA protein

ZEBRA (BamHI Z Epstein-Barr virus replication activator, also known as Zta and BZLF1) is an early lytic protein of EBV encoded by BZLF1.

Structure

ZEBRA is a homodimer. Each subunit has 245 amino acid residues. It has a basic leucine zipper domain, a characteristic of many transcription factors.

Function

Regulation of lytic replication

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.

Induction of DNA damage response

It has been shown to induce DNA damage response associated with the activation of EBV lytic cycle; the DNA damage response in turn allow maximal expression of lytic gene products, including ZEBRA itself and EA-D, the EBV DNA polymerase processivity factor.

Research

BZLF1 expression level is used as an indicator for lytic EBV infection BZLF1 transfection is also used to induce EBV viral production.Kenney et al. (2017). Latent Membrane Protein 1 (LMP1) and LMP2A Collaborate To Promote Epstein-Barr Virus-Induced B Cell Lymphomas in a Cord Blood-Humanized Mouse Model but Are Not Essential. Journal of Virology. Volume 91. Issue 7. (see Materials and Methods: Production of infectious virus)

References

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External links

Wikigenes

National Center for Biotech Info
Viral genes Epstein–Barr virus