Activation of Vav by Nef induces cytoskeletal rearrangements and downstream effector functions.

Nef of primate lentiviruses is critical for high levels of viremia and the progression to AIDS. Nef associates with and activates a serine/threonine kinase (Nef-associated kinase [NAK]) via the small GTPases Rac1 and Cdc42. We identified the protooncogene and guanine nucleotide exchange factor Vav as the specific binding partner of Nef proteins from HIV-1 and SIV. The interaction between Nef and Vav led to increased activity of Vav and its downstream effectors. Both cytoskeletal changes and the activation of c-Jun N-terminal kinase (JNK) were observed. Furthermore, a dominant-negative Vav protein inhibited NAK activation and viral replication. Thus, the interaction between Nef and Vav initiates a signaling cascade that changes structural and physiological parameters in the infected cell.

[1]  C. Cheng‐Mayer,et al.  Activation of PAK by HIV and SIV Nef: importance for AIDS in rhesus macaques , 1996, Current Biology.

[2]  R. Treisman,et al.  Activation of RhoA and SAPK/JNK signalling pathways by the RhoA‐specific exchange factor mNET1 , 1998, The EMBO journal.

[3]  J. Kuriyan,et al.  Activation of the Sire-family tyrosine kinase Hck by SH3 domain displacement , 1997, Nature.

[4]  J. Skowroński,et al.  Altered T cell activation and development in transgenic mice expressing the HIV‐1 nef gene. , 1993, The EMBO journal.

[5]  R. Treisman,et al.  The Rho family GTPases RhoA, Racl , and CDC42Hsregulate transcriptional activation by SRF , 1995, Cell.

[6]  M. Karin,et al.  Selective activation of the JNK signaling cascadeand c-Jun transcriptional activity by the small GTPases Rac and Cdc42Hs , 1995, Cell.

[7]  C. Cheng‐Mayer,et al.  HIV-1 Nef leads to inhibition or activation of T cells depending on its intracellular localization. , 1994, Immunity.

[8]  A. Abo,et al.  CDC42 and Rac1 are implicated in the activation of the Nef-associated kinase and replication of HIV-1 , 1996, Current Biology.

[9]  J. Garcia,et al.  Serine phosphorylation-independent downregulation of cell-surface CD4 by nef , 1991, Nature.

[10]  R. Flavell,et al.  The JNK Pathway Regulates the In Vivo Deletion of Immature CD4+CD8+ Thymocytes , 1998, The Journal of experimental medicine.

[11]  D. Trono,et al.  Nef stimulates human immunodeficiency virus type 1 proviral DNA synthesis , 1995, Journal of virology.

[12]  J. Frost,et al.  Differential Effects of PAK1-activating Mutations Reveal Activity-dependent and -independent Effects on Cytoskeletal Regulation* , 1998, The Journal of Biological Chemistry.

[13]  M. Foti,et al.  Mechanism of Nef‐induced CD4 endocytosis: Nef connects CD4 with the μ chain of adaptor complexes , 1998, The EMBO journal.

[14]  J. S. Sullivan,et al.  Genomic Structure of an Attenuated Quasi Species of HIV-1 from a Blood Transfusion Donor and Recipients , 1995, Science.

[15]  B. Chait,et al.  Crystal Structure of the Conserved Core of HIV-1 Nef Complexed with a Src Family SH3 Domain , 1996, Cell.

[16]  A. Guimond,et al.  Nef Harbors a Major Determinant of Pathogenicity for an AIDS-like Disease Induced by HIV-1 in Transgenic Mice , 1998, Cell.

[17]  John L. Sullivan,et al.  Absence of intact nef sequences in a long-term survivor with nonprogressive HIV-1 infection , 1995 .

[18]  R. Desrosiers,et al.  Importance of the nef gene for maintenance of high virus loads and for development of AIDS , 1991, Cell.

[19]  C. Cheng‐Mayer,et al.  A Conserved Domain and Membrane Targeting of Nef from HIV and SIV Are Required for Association with a Cellular Serine Kinase Activity (*) , 1995, The Journal of Biological Chemistry.

[20]  O. Danos,et al.  Human immunodeficiency virus type 1 Nef increases the efficiency of reverse transcription in the infected cell , 1995, Journal of virology.

[21]  W. Parks,et al.  Human Immunodeficiency Virus Type 1 Genome Activation Induced by Human T-Cell Leukemia Virus Type 1 Tax Protein Is through Cooperation of NF-κB and Tat , 1998, Journal of Virology.

[22]  L. Zon,et al.  Role of SAPK/ERK kinase-1 in the stress-activated pathway regulating transcription factor c-Jun , 1994, Nature.

[23]  K. Tedford,et al.  Vav links antigen-receptor signaling to the actin cytoskeleton. , 1998, Seminars in immunology.

[24]  P. Cossart,et al.  Interaction of invasive bacteria with host signaling pathways. , 1998, Current opinion in cell biology.

[25]  K. Schuebel,et al.  Isolation and characterization of murine vav2, a member of the vav family of proto-oncogenes. , 1996, Oncogene.

[26]  F. Nappi,et al.  gag, vif, and nef Genes Contribute to the Homologous Viral Interference Induced by a Nonproducer Human Immunodeficiency Virus Type 1 (HIV-1) Variant: Identification of Novel HIV-1-Inhibiting Viral Protein Mutants , 1998, Journal of Virology.

[27]  R. Perona,et al.  Multiple Signalling Pathways Lead to the Activation of the Nuclear Factor κB by the Rho Family of GTPases* , 1998, The Journal of Biological Chemistry.

[28]  M. Way,et al.  Viral manipulations of the actin cytoskeleton. , 1997, Trends in microbiology.

[29]  G. Aldrovandi,et al.  Requirement of human immunodeficiency virus type 1 nef for in vivo replication and pathogenicity , 1994, Journal of virology.

[30]  P. Crespo,et al.  The small GTP-binding proteins Rac1 and Cdc42regulate the activity of the JNK/SAPK signaling pathway , 1995, Cell.

[31]  C. Cheng‐Mayer,et al.  HIV-1 Nef association with cellular serine kinase correlates with enhanced virion infectivity and efficient proviral DNA synthesis. , 1996, Virology.

[32]  Mario Stevenson,et al.  SH3-mediated Hck Tyrosine Kinase Activation and Fibroblast Transformation by the Nef Protein of HIV-1* , 1997, The Journal of Biological Chemistry.

[33]  J. Wu,et al.  Vav and SLP-76 interact and functionally cooperate in IL-2 gene activation. , 1996, Immunity.

[34]  K. Schuebel,et al.  Phosphotyrosine-dependent activation of Rac-1 GDP/GTP exchange by the vav proto-oncogene product , 1997, Nature.

[35]  D. Cowburn,et al.  A single amino acid in the SH3 domain of Hck determines its high affinity and specificity in binding to HIV‐1 Nef protein. , 1995, The EMBO journal.

[36]  C. Cheng‐Mayer,et al.  Human immunodeficiency virus type 1 Nef associates with a cellular serine kinase in T lymphocytes. , 1994, Proceedings of the National Academy of Sciences of the United States of America.

[37]  A. Hall,et al.  Rho GTPases and the actin cytoskeleton. , 1998, Science.

[38]  G. Nolan,et al.  Host Control of HIV-1 Parasitism in T Cells by the Nuclear Factor of Activated T Cells , 1998, Cell.

[39]  D. Richman,et al.  The growth advantage conferred by HIV-1 nef is determined at the level of viral DNA formation and is independent of CD4 downregulation. , 1995, Virology.

[40]  J. Skowroński,et al.  Separable functions of Nef disrupt two aspects of T cell receptor machinery: CD4 expression and CD3 signaling , 1997, The EMBO journal.

[41]  D. Baltimore,et al.  Proline‐rich (PxxP) motifs in HIV‐1 Nef bind to SH3 domains of a subset of Src kinases and are required for the enhanced growth of Nef+ viruses but not for down‐regulation of CD4. , 1995, The EMBO journal.

[42]  A. Rice,et al.  Tat-Associated Kinase, TAK, Activity Is Regulated by Distinct Mechanisms in Peripheral Blood Lymphocytes and Promonocytic Cell Lines , 1998, Journal of Virology.

[43]  R. Treisman,et al.  The p38 and ERK MAP kinase pathways cooperate to activate Ternary Complex Factors and c‐fos transcription in response to UV light. , 1996, The EMBO journal.

[44]  J. Marsh,et al.  Human immunodeficiency virus type 1 Nef associates with a member of the p21-activated kinase family , 1996, Journal of virology.

[45]  G. Bokoch,et al.  Membrane targeting of p21‐activated kinase 1 (PAK1) induces neurite outgrowth from PC12 cells , 1998, The EMBO journal.

[46]  M. Greenberg,et al.  The SH3 domain‐binding surface and an acidic motif in HIV‐1 Nef regulate trafficking of class I MHC complexes , 1998, The EMBO journal.

[47]  S. Arold,et al.  The crystal structure of HIV-1 Nef protein bound to the Fyn kinase SH3 domain suggests a role for this complex in altered T cell receptor signaling. , 1997, Structure.

[48]  M. Greenberg,et al.  Co‐localization of HIV‐1 Nef with the AP‐2 adaptor protein complex correlates with Nef‐induced CD4 down‐regulation , 1997, The EMBO journal.

[49]  S. Arold,et al.  RT loop flexibility enhances the specificity of Src family SH3 domains for HIV-1 Nef. , 1998, Biochemistry.

[50]  P. Luciw,et al.  Role of the SH3-Ligand Domain of Simian Immunodeficiency Virus Nef in Interaction with Nef-Associated Kinase and Simian AIDS in Rhesus Macaques , 1998, Journal of Virology.

[51]  J. Penninger,et al.  Vav Regulates Peptide-specific Apoptosis in Thymocytes , 1998, The Journal of experimental medicine.

[52]  F. Lemonnier,et al.  Endocytosis of major histocompatibility complex class I molecules is induced by the HIV–1 Nef protein , 1996, Nature Medicine.

[53]  Steven G. Deeks,et al.  Directly measured kinetics of circulating T lymphocytes in normal and HIV-1-infected humans , 1999, Nature Medicine.

[54]  W C Greene,et al.  Dissociation of the CD4 downregulation and viral infectivity enhancement functions of human immunodeficiency virus type 1 Nef , 1995, Journal of virology.

[55]  F. Brodsky,et al.  Interactions between HIV1 Nef and vacuolar ATPase facilitate the internalization of CD4. , 1998, Immunity.

[56]  S. Le Gall,et al.  Nef interacts with the mu subunit of clathrin adaptor complexes and reveals a cryptic sorting signal in MHC I molecules. , 1998, Immunity.

[57]  M. Vihinen,et al.  SH3-Domain binding function of HIV-1 Nef is required for association with a PAK-related kinase. , 1998, Virology.

[58]  S. Bagrodia,et al.  Cytoskeletal Reorganization by G Protein-Coupled Receptors Is Dependent on Phosphoinositide 3-Kinase γ, a Rac Guanosine Exchange Factor, and Rac , 1998, Molecular and Cellular Biology.

[59]  L. Lim,et al.  A Conserved Negative Regulatory Region in αPAK: Inhibition of PAK Kinases Reveals Their Morphological Roles Downstream of Cdc42 and Rac1 , 1998, Molecular and Cellular Biology.

[60]  J. Garcia,et al.  The association of Nef with a cellular serine/threonine kinase and its enhancement of infectivity are viral isolate dependent , 1996, Journal of virology.

[61]  S. Grzesiek,et al.  The solution structure of HIV-1 Nef reveals an unexpected fold and permits delineation of the binding surface for the SH3 domain of Hck tyrosine protein kinase , 1996, Nature Structural Biology.

[62]  O. Hobert,et al.  Novel signaling pathway suggested by SH3 domain-mediated p95vav/heterogeneous ribonucleoprotein K interaction. , 1994, The Journal of biological chemistry.

[63]  M. Karin,et al.  Cooperation between Syk and Rac1 leads to synergistic JNK activation in T lymphocytes. , 1998, Immunity.

[64]  C. Der,et al.  Lck regulates Vav activation of members of the Rho family of GTPases , 1997, Molecular and cellular biology.

[65]  K. Schuebel,et al.  Phosphorylation‐dependent and constitutive activation of Rho proteins by wild‐type and oncogenic Vav‐2 , 1998, The EMBO journal.

[66]  R. Desrosiers,et al.  A role for natural simian immunodeficiency virus and human immunodeficiency virus type 1 nef alleles in lymphocyte activation , 1997, Journal of virology.