Article

ZAP-70 kinase regulates HIV cell-to-cell spread and virological synapse formation.

Groupe Virus et Immunité, Institut Pasteur, CNRS URA1930, France.
The EMBO Journal (Impact Factor: 10.75). 02/2007; 26(2):516-26. DOI: 10.1038/sj.emboj.7601509
Source: PubMed

ABSTRACT HIV efficiently spreads in lymphocytes, likely through virological synapses (VSs). These cell-cell junctions share some characteristics with immunological synapses, but cellular proteins required for their constitution remain poorly characterized. We have examined here the role of ZAP-70, a key kinase regulating T-cell activation and immunological synapse formation, in HIV replication. In lymphocytes deficient for ZAP-70, or expressing a kinase-dead mutant of the protein, HIV replication was strikingly delayed. We have characterized further this replication defect. ZAP-70 was dispensable for the early steps of viral cycle, from entry to expression of viral proteins. However, in the absence of ZAP-70, intracellular Gag localization was impaired. ZAP-70 was required in infected donor cells for efficient cell-to-cell HIV transmission to recipients and for formation of VSs. These results bring novel insights into the links that exist between T-cell activation and HIV spread, and suggest that HIV usurps components of the immunological synapse machinery to ensure its own spread through cell-to-cell contacts.

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Available from: Andrés Alcover, Dec 23, 2013
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