title: HIV-1 Nef Impairs the Formation of Calcium Membrane Territories Controlling the Signaling Nanoarchitecture at the Immunological Synapse.
abstract: The ability of HIV-1 to replicate and to establish long-term reservoirs is strongly influenced by T cell activation. Through the use of membrane-tethered, genetically encoded calcium (Ca2+) indicators, we were able to detect for the first time, to our knowledge, the formation of Ca2+territories and determine their role in coordinating the functional signaling nanostructure of the synaptic membrane. Consequently, we report a previously unknown immune subversion mechanism involving HIV-1 exploitation, through its Nef accessory protein, of the interconnectivity among three evolutionarily conserved cellular processes: vesicle traffic, signaling compartmentalization, and the second messenger Ca2+We found that HIV-1 Nef specifically associates with the traffic regulators MAL and Rab11b compelling the vesicular accumulation of Lck. Through its association with MAL and Rab11b, Nef co-opts Lck switchlike function driving the formation Ca2+membrane territories, which, in turn, control the fusion of LAT-transporting Rab27 and Rab37 vesicles and the formation of LAT nanoclusters at the immunological synapse. Consequently, HIV-1 Nef disengages TCR triggering from the generation of p-LAT and p-SLP nanoclusters driving TCR signal amplification and diversification. Altogether our results indicate that HIV-1 exploits the interconnectivity among vesicle traffic, Ca2+membrane territories, and signaling nanoclusters to modulate T cell signaling and function.
authors: Immunobiology and Pathogenesis Group, Chronic Diseases Research Center, NOVA Medical School, NOVA University of Lisbon, 1150-082 Lisbon, Portugal.
authors: Joana G
authors: 0000-0003-2318-3893
authors: JG
authors: Silva
authors: Unit of Imaging and Cytometry, Gulbenkian Institute for Science, 2780-156 Oeiras, Portugal.
authors: Nuno P
authors: 0000-0002-8104-0957
authors: NP
authors: Martins
authors: Quantitative Imaging and Nanobiophysics Group, Medical Research Council Laboratory for Molecular Cell Biology, University College London, London, United Kingdom; and.|Department of Cell and Developmental Biology, University College London, London WC1E 6BT, United Kingdom.
authors: Ricardo
authors: 0000-0002-2043-5234
authors: R
authors: Henriques
authors: Immunobiology and Pathogenesis Group, Chronic Diseases Research Center, NOVA Medical School, NOVA University of Lisbon, 1150-082 Lisbon, Portugal; helena.soares@nms.unl.pt.
authors: Helena
authors: 0000-0002-5881-3843
authors: H
authors: Soares
mesh_terms: D002118:Calcium / Q000378:metabolism*; D057809:HEK293 Cells; D015497:HIV-1 / Q000276:immunology / Q000502:physiology*; D006801:Humans; D054992:Immunological Synapses / Q000378:metabolism* / Q000648:ultrastructure; D019169:Jurkat Cells; D008213:Lymphocyte Activation; D019860:Lymphocyte Specific Protein Tyrosine Kinase p56(lck) / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000378:metabolism; D010766:Phosphorylation; D011948:Receptors, Antigen, T-Cell / Q000276:immunology; D017472:Receptors, Interleukin-1 / Q000378:metabolism; D015398:Signal Transduction; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D054311:nef Gene Products, Human Immunodeficiency Virus / Q000737:chemistry / Q000276:immunology / Q000378:metabolism*; D020691:rab GTP-Binding Proteins / Q000378:metabolism; D000075745:rab27 GTP-Binding Proteins; D000099193:rab11 GTP-Binding Proteins
chemical_list: D002118:Calcium; D019860:Lymphocyte Specific Protein Tyrosine Kinase p56(lck); D008562:Membrane Glycoproteins; D011948:Receptors, Antigen, T-Cell; D017472:Receptors, Interleukin-1; D054311:nef Gene Products, Human Immunodeficiency Virus; D020691:rab GTP-Binding Proteins; D000075745:rab27 GTP-Binding Proteins; D000099193:rab11 GTP-Binding Proteins; C434984:TIRAP protein, human; C571080:Rab37 protein, human; C066694:RAB27A protein, human