Related Experiment Video
Updated: May 2, 2026
06:38
Establishment of Epstein-Barr Virus Growth-transformed Lymphoblastoid Cell Lines
Published on: November 8, 2011
40.5K
Identification of Epstein-Barr virus BORF2 sequences required for APOBEC3B relocalization.
Farren Clark1, Michael A Carpenter2, Reuben S Harris2
1Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada.
Journal of Virology
|August 21, 2025
Summary
Herpesviruses like EBV use the BORF2 protein to move APOBEC3B out of the nucleus, protecting viral DNA from mutation. A conserved motif and SUMOylation are key to this process.
Area of Science:
- Virology
- Molecular Biology
- Immunology
Background:
- Epstein-Barr virus (EBV) establishes lifelong infections and must protect its replicating DNA from host APOBEC3B deaminase.
- Herpesviruses employ viral proteins to counteract APOBEC3B, a host factor that mutates viral DNA.
Purpose of the Study:
- To investigate the conserved mechanisms herpesviruses use to sequester APOBEC3B.
- To identify the viral protein motifs and modifications involved in APOBEC3B relocalization and cytoplasmic body formation.
Main Methods:
- Analysis of conserved motifs (IPAM) in EBV BORF2, KSHV ORF61, and HSV-1 UL39.
- Investigating the role of a SUMO-modified site (K741) in BORF2.
- Characterizing cytoplasmic body formation and properties in the presence of viral proteins and APOBEC3B.
Main Results:
- A conserved IPAM motif is critical for BORF2, ORF61, and UL39 interaction with and relocalization of APOBEC3B.
- BORF2-induced cytoplasmic bodies require APOBEC3B, while UL39 bodies exhibit aggresome-like properties.
- SUMOylation at BORF2 K741 is important for cytoplasmic body formation with APOBEC3B, including in EBV-infected cells.
Conclusions:
- Herpesviruses utilize conserved protein motifs to disable APOBEC3B, safeguarding their genomes.
- SUMOylation of BORF2 plays a significant role in sequestering APOBEC3B into cytoplasmic bodies.
- Understanding these mechanisms is crucial for maintaining herpesvirus integrity and infectivity.
Related Concept Videos
02:28Leaky Scanning
4.5K
During most eukaryotic translation processes, the small 40S ribosome subunit scans an mRNA from its 5' end until it encounters the first start AUG codon. The large 60S ribosomal subunit then joins the smaller one to initiate protein synthesis. The location of the translation initiation is largely determined by the nucleotides near the start codon as there may be multiple translation initiation sites present on the mRNA. Marilyn Kozak discovered that the sequence RCCAUGG (where R...
4.5K
01:26DNA Bacteriophages
1.6K
Bacteriophages, or phages, are viruses that specifically infect bacteria, utilizing their genetic material to hijack host cellular machinery for replication. DNA bacteriophages employ single-stranded DNA (ssDNA) or double-stranded DNA (dsDNA) genomes. These phages exhibit diverse replication strategies and host interactions, influencing their ecological roles and applications in biotechnology and medicine.ssDNA BacteriophagesssDNA phages, with their small genomes, utilize unique strategies to...
1.6K
01:29Viruses with RNA Genomes
1.5K
RNA viruses are categorized into positive-strand, negative-strand, or double-stranded groups based on their genomic structure and replication mechanisms. This classification dictates how they exploit host cellular machinery for protein synthesis and replication. Some RNA viruses also utilize reverse transcription as part of their life cycle, further diversifying their replication strategies.Positive-Strand RNA VirusesPositive-strand RNA viruses have genomes that function directly as messenger...
1.5K