Latent Membrane Protein 2A of Epstein-Barr Virus Binds WW Domain E3 Protein-Ubiquitin Ligases That Ubiquitinate B-Cell Tyrosine Kinases
Latent Membrane Protein 2A of Epstein-Barr Virus Binds WW Domain E3 Protein-Ubiquitin Ligases That Ubiquitinate B-Cell Tyrosine Kinases
The latent membrane protein (LMP) 2A of Epstein-Barr virus (EBV) is implicated in the maintenance of viral latency and appears to function in part by inhibiting B-cell receptor (BCR) signaling. The N-terminal cytoplasmic region of LMP2A has multiple tyrosine residues that upon phosphorylation bind the SH2 domains of the Syk tyrosine kinase and the Src family kinase Lyn. The LMP2A N-terminal region also has two conserved PPPPY motifs. Here we show that the PPPPY motifs of LMP2A bind multiple WW domains of E3 protein-ubiquitin ligases of the Nedd4 family, including AIP4 and KIAA0439, and demonstrate that AIP4 and KIAA0439 form physiological complexes with LMP2A in EBV-positive B cells. In addition to a C2 domain and four WW domains, these proteins have a C-terminal Hect catalytic domain implicated in the ubiquitination of target proteins. LMP2A enhances Lyn and Syk ubiquitination in vivo in a fashion that depends on the activity of Nedd4 family members and correlates with destabilization of the Lyn tyrosine kinase. These results suggest that LMP2A serves as a molecular scaffold to recruit both B-cell tyrosine kinases and C2/WW/Hect domain E3 protein-ubiquitin ligases. This may promote Lyn and Syk ubiquitination in a fashion that contributes to a block in B-cell signaling. LMP2A may potentiate a normal mechanism by which Nedd4 family E3 enzymes regulate B-cell signaling.
- University of Toronto Canada
- Hospital for Sick Children Canada
- Mount Sinai Hospital Canada
- Karolinska Institute Sweden
- Lunenfeld-Tanenbaum Research Institute Canada
B-Lymphocytes, Enzyme Precursors, Binding Sites, Base Sequence, Endosomal Sorting Complexes Required for Transport, Arabidopsis Proteins, Nedd4 Ubiquitin Protein Ligases, Amino Acid Motifs, Calcium-Binding Proteins, Molecular Sequence Data, Intracellular Signaling Peptides and Proteins, Protein-Tyrosine Kinases, Ligases, Repressor Proteins, Mice, Mutation, Animals, Humans, Amino Acid Sequence, Carrier Proteins
B-Lymphocytes, Enzyme Precursors, Binding Sites, Base Sequence, Endosomal Sorting Complexes Required for Transport, Arabidopsis Proteins, Nedd4 Ubiquitin Protein Ligases, Amino Acid Motifs, Calcium-Binding Proteins, Molecular Sequence Data, Intracellular Signaling Peptides and Proteins, Protein-Tyrosine Kinases, Ligases, Repressor Proteins, Mice, Mutation, Animals, Humans, Amino Acid Sequence, Carrier Proteins
9 Research products, page 1 of 1
- 2017IsRelatedTo
- 2018IsRelatedTo
- 2017IsRelatedTo
- 2018IsRelatedTo
- 2017IsRelatedTo
- 2017IsRelatedTo
citations This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).147 popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.Top 10% influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).Top 10% impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.Top 1%
