Human protein: T-cell surface glycoprotein CD4 isoform 1 precursor
Human protein sequence: MNRGVPFRHLLLVLQLALLPAATQGKKVVLGKKGDTVELTCTASQKKSIQFHWKNSNQIKILGNQGSFLTKGPSKLNDRADSRRSLWDQGNFPLIIKNLKIEDSDTYICEVEDQKEEVQLLVFGLTANSDTHLLQGQSLTLTLESPPGSSPSVQCRSPRGKNIQGGKTLSVSQLELQDSGTWTCTVLQNQKKVEFKIDIVVLAFQKASSIVYKKEGEQVEFSFPLAFTVEKLTGSGELWWQAERASSSKSWITFDLKNKEVSVKRVTQDPKLQMGKKLPLHLTLPQALPQYAGSGNLTLALEAKTGKLHQEVNLVVMRATQLQKNLTCEVWGPTSPKLMLSLKLENKEAKVSKREKAVWVLNPEAGMWQCLLSDSGQVLLESNIKVLPTWSTPVQPMALIVLGGVAGLLLFIGLGIFFCVRCRHRRRQAERMSQIKRLLSEKKTCQCPHRFQKTCSPI

HIV protein: Envelope transmembrane glycoprotein gp41
Interaction type: interacts with
Description: The HIV-1 transmembrane glycoprotein gp41 is an amino acceptor and donor substrate for transglutaminase in vitro; soluble CD4 can block the transglutaminase-catalyzed incorporation of the polyamine spermidine into HIV-1 gp41
HIV protein sequence: AVGIGALFLGFLGAAGSTMGAASMTLTVQARQLLSGIVQQQNNLLRAIEAQQHLLQLTVWGIKQLQARILAVERYLKDQQLLGIWGCSGKLICTTAVPWNASWSNKSLEQIWNHTTWMEWDREINNYTSLIHSLIEESQNQQEKNEQELLELDKWASLWNWFNITNWLWYIKLFIMIVGGLVGLRIVFAVLSIVNRVRQGYSPLSFQTHLPTPRGPDRPEGIEEEGGERDRDRSIRLVNGSLALIWDDLRSLCLFSYHRLRDLLLIVTRIVELLGRRGWEALKYWWNLLQYWSQELKNSAVSLLNATAIAVAEGTDRVIEVVQGACRAIRHIPRRIRQGLERILL

HIV protein: Envelope transmembrane glycoprotein gp41
Interaction type: complexes with
Description: HIV-1 gp120 and gp41 form a transitional complex with the CD4 receptor and CCR5/CXCR4 coreceptors during virus-cell and cell-cell membrane fusion
HIV protein sequence: AVGIGALFLGFLGAAGSTMGAASMTLTVQARQLLSGIVQQQNNLLRAIEAQQHLLQLTVWGIKQLQARILAVERYLKDQQLLGIWGCSGKLICTTAVPWNASWSNKSLEQIWNHTTWMEWDREINNYTSLIHSLIEESQNQQEKNEQELLELDKWASLWNWFNITNWLWYIKLFIMIVGGLVGLRIVFAVLSIVNRVRQGYSPLSFQTHLPTPRGPDRPEGIEEEGGERDRDRSIRLVNGSLALIWDDLRSLCLFSYHRLRDLLLIVTRIVELLGRRGWEALKYWWNLLQYWSQELKNSAVSLLNATAIAVAEGTDRVIEVVQGACRAIRHIPRRIRQGLERILL

HIV protein: Nef
Interaction type: downregulates
Description: High levels of CD4 on the surface of an HIV-1 producing cell block viral infectivity by interfering with incorporation of HIV-1 envelope into the virion; HIV-1 Nef and Vpu inhibit this block by downregulating CD4 from the cell surface
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: CD4 downregulation by HIV-1 Nef enhances the efficiency of HIV-1 replication in both activated human primary T lymphocytes and lymphoid tissues; Nef-induced CD4 downregulation correlates with severe depletion of CD4+ T cells in lymphoid tissues
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: The functional ability of HIV-1 Nef to downregulate CD4, but not MHC class I, is associated with Nef-mediated enhancement of HIV-1 pathogenicity in severe combined immunodeficiency (SCID) mice implanted with human fetal thymus and liver
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: modulates
Description: Different levels of CD4 modulation are induced by different HIV-1 Nef proteins derived from HIV-1 infected adults and children
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 Nef downregulates CD4 in Jurkat cells in a concentration-dependent manner
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: The HIV-1 Nef mutant F12-HIVNef, containing three rare amino acid substitutions, G(140)E, V(153)L and E(177)G, represses Nef-induced accelerated rates of CD4 internalization and p62NAK activation
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: binds
Description: The presence of an alpha-helix in CD4, which extends from residues Gln403 to Arg406, promotes the binding of CD4 to HIV-1 Nef
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: A dileucine motif in the cytoplasmic tail of CD4 is not required for HIV-1 Nef binding in insect cells, but is essential for Nef-induced CD4 downregulation
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: Expression of HIV-1 Nef in human monocyte-derived dendritic cells using an adenovirus based delivery system decreases CD4 levels, but has no effect on class I MHC
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: The Nef protein from the primary virus isolate HIV-1 KS2 lacks two glutamic acid residues (EE154-5) and has a decreased ability to downregulate CD4
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 expressing Nef proteins defective in CD4 downregulation activity retain wild-type levels of infectivity in single-round assays, but exhibit delayed replication kinetics and lower titers compared to the wild-type virus in monocyte-derived macrophages
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 group N and group O Nef alleles only weakly downregulate CD4, CD28, and class I and II MHC molecules
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 Nef forms a ternary complex with ARF1 and beta-COP in endosomes, which facilitates Nef-induced downregulation and transport of CD4 to acidic late-endosomal compartments
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: PMA treatment of T cells expressing HIV-1 Nef, which downregulates CD4, restores cell surface CD4 up to 35%; mutations in the phosphorylation sites of the CD4 cytoplasmic tail (Ser408 and Ser415) abolish this effect of PMA
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 Nef downregulates CD4 molecules from the cell surface of T, B, peripheral blood mononuclear and monocyte/macrophage cell lines as well as non-lymphoid cell lines
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: Experiments using both a recombinant HIV-1 Integrase-defective virus and a diketo acid Integrase inhibitor demonstrate that HIV-1 Nef expressed from extra chromosomal DNA (E-DNA) downregulates CD4 surface expression on primary CD4(+) T lymphocytes
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: interacts with
Description: Bioluminescence resonance energy transfer (BRET) and co-immunoprecipitation assays have been used to demonstrate the interaction of HIV-1 Nef and CD4 in intact human cells
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 Nef-mediated CD4 downregulation is profoundly inhibited by the synergistic effect of Eps15DIII, a dominant negative mutant of Eps involved in endocytosis and RNA interference of AP-2 expression
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 Nef induces drastic and moderate downregulation of CD4 and MHC-I in resting CD4(+) T lymphocytes, respectively, but markedly upregulates cell surface levels of the MHC-II invariant chain CD74
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: CD4 and MHC-1 downregulation are highly conserved in primary HIV-1 Nef alleles from brain and lymphoid tissues, but Pak2 activation is highly variable
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 Vpr increases expression of Nef protein from integrase-defective HIV-1. The Vpr-mediated expression of Nef from IN-minus HIV-1 results in CD4 downregulation
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: L37, P78 and E177 residues of HIV-1 Nef are required for its effect on CD4 internalization and recycling but dispensable for Nef-induced retention and degradation of intracellular CD4
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: Single mutation at the ubiquitination residue K144 or at the tyrosine motif Y202F203 in HIV-1 Nef greatly impairs Nef-mediated CD4 downregulation
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: enhances
Description: HIV-1 Nef enhances the infectivity of CD4-chemokine receptor-pseudotyped HIV-1 for target cells expressing HIV-1 Env. Virus-producing cells expressing dominant-negative dynamin 2 (K44A) selectively inhibits these receptor-pseudotyped virions
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 Nef-Vpr fusion proteins are efficiently incorporated into HIV-1 particles and possess CD4 downregulation activity in target cells
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: complexes with
Description: K295, K297, K298, and R340 basic residues on the AP-2 alpha subunit are required for its binding to HIV-1 Nef. The K297 and R340 residues are required for Nef-induced CD4 downregulation and the cooperative assembly of a Nef-CD4-AP-2 complex
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 Nef mutants LLAA and delta12-39 significantly impair downregulation of CD4. Nef LLAA mutant fails to interact with the endocytic machinery and Nef delta12-39 mutant lacks the interaction with the Nef-associated kinase complex
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: degrades
Description: HIV-1 Nef targets CD4 to CD63-containing lysosomes for Nef-induced degradation of CD4, which requires the VPS4-mediated ESCRT machinery
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: Expression of p56(lck) in nonlymphoid CD4-expressing cells restores the ability of Nef in order to increase the internalization rate of CD4
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: An intact Nef dimerization interface, including the multiple hydrophobic (I109, L112, Y115, and F121) and electrostatic (R105 and D123) residues, is required for Nef-induced CD4 downregulation in cells
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: An intact hydrophobic interface (residues I109, L112, Y115, and F121) is essential for HIV-1 Nef dimerization in cells and is required for Nef-mediated CD4 receptor downregulation
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: CD4 downregulation by HIV-1 Nef is independent of the level of CD4 mRNA expressed in cells and of the level of CD4 serine phosphorylation
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: interacts with
Description: HIV-1 Nef interacts with CD4 in living cells
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 Nef expression from unintegrated HIV-1 DNA downregulates the surface levels of CD4, CCR5, and CXCR4 on T-lymphocytes and monocytes
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: interacts with
Description: TPCK and TLCK alkylation reagents chemically modify HIV-1 Nef at residues Cys55 and Cys206. Cys55 modification reduces the strength of the interaction between Nef and CD4 tail peptide
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 Nef drastically reduces the ratio of CD4 dimers/monomers
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: beta-COP as a cellular cofactor is required for HIV-1 Nef-mediated HLA-A2, CD4, and CD8 downregulation
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: Functional ARF1 is required for HIV-1 Nef-dependent endogenous HLA-A2 and CD4 downregulation in HIV-infected primary T cells
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: The hydrophobic region (residues 168-173) downstream of the HIV-1 Nef dileucine motif (L164L165) is involved in HIV-1 Nef-mediated CD4 downregulation
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: Interaction of HIV-1 Nef with AP-2 alpha-sigma dimer is required for Nef-mediated CD4 downregulation. The dileucine L164L165 and M168L170 motifs bind to the sigma unit, while the acidic motif E174 and D175 binds to the alpha unit
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 Nef clones, isolated from plasma of elite controllers (EC) and chronic progressors (CP), show significantly lower CD4 downregulation activity in EC than that in CP
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 Nef clones obtained from chronic patients infected with HIV-1 subtypes A, B, C or D show a functional hierarchy of subtype B > A/D > C for Nef-mediated CD4 downregulation
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: interacts with
Description: Deletion of both HIV-1 nef and vpu genes enhance a significant engagement between HIV-1 gp120 and CD4 at the cell surface, suggesting Nef and Vpu prevent the exposure of epitopes recognized by anti-gp120 antibody-dependent cell-mediated cytotoxicity
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 Nef mutants D108K, R134E, E177K, DD174/175AA do not downregulate CD4 on cell surface of HeLa cells
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: Neffin, a camelid single-domain antibody fragment (termed sdAb19) fused to the SH3 domain of Nef, strongly binds to HIV-1 Nef with a stoichiometric 2:2 ratio and inhibits Nef-mediated downregulation of CD4 in HeLa-CD4 cells
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 Nef clones from acute controllers display a lesser ability to downregulate CD4 and HLA class I from the cell surface, and a reduced ability to enhance virion infectivity compared to those from acute progressors
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: degrades
Description: HIV-1 Nef-mediated CD4 degradation requires ALIX and interaction of Nef with ALIX in endosomes containing CD4 in cells
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 isolate R3A Nef mutants G2, WL58, RR106, LL165, E160NNSLL165, and DD175 fail to induce release of IFN-alpha in pDCs, suggesting that the Nef function responsible for CD4 downregulation is crucial for pDCs stimulation by R3A
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 (NL4-3) Nef downregulates CD4 via a cullin-RING E3 ubiquitin ligase complex- independent mechanism
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: interacts with
Description: HIV-1 Nef core domain directly interacts with CD4 and is highly conserved amongst Nef from [the] HIV-1/-2/SIV strains [tested] in 293T cells as shown by FACS-Forster resonance energy transfer (FRET)- and site-directed mutagenesis-based experiments
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 Nef downregulates CD4 in primary HIV-1 infected CD4+ T cells
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 Nef and Vpu downregulate CD4 expression; Nef and Vpu deletions reverse CD4 downmodulation in an additive fashion
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 NL4-3, Sk68, SF2, and clinical isolates downregulate CD4 surface expression
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 NL4-3 and SK68 Nef downregulate CD4, which is dependent upon a serine at position 88 in Nef
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 Nef and Vpu downregulate CD4 in an additive manner, which when inhibited allows for antibodies to bind CD4-Env and drive ADCC
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 (SF2) Nef downregulates CD4; downregulation is dependent on the dileucine motif in Nef
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 NL4-3 Nef downregulates CD4, which requires the CPG-motif in Nef
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 Nef clinical isolates from chronic progressors downregulate CD4 to greater amounts than from elite controllers
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 NA7 Nef downregulates CD4 surface expression; downregulation is dependent upon amino acid D186 in Nef
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: Mutational analysis of HIV-1 Nef shows that a membrane targeting domain (residues 2-7) and a conserved glutamic acid-rich segment (residues 60-71) are required for CD4 downregulation but not for viral infectivity enhancement
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 Nef-mediated downregulation of CD4 is induced by an accelerated dissociation of the T-cell tyrosine kinase Lck and CD4, and a decrease in the half-life of CD4
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: A dileucine motif in the CD4 cytoplasmic domain is required for its downregulation by HIV-1 Nef; cysteine residues in the cytoplasmic domain of CD4 are essential for the binding of Lck but are not required for Nef-induced downregulation
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: CEM cells stably transfected with a replication-defective provirus of HIV-1 that has a rev-splicing mutation and expresses an intact nef gene have markedly reduced cell surface expression of CD4
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: degrades
Description: HIV-1 Nef-induced CD4 degradation is regulated by a highly conserved diacidic-based motif in Nef that acts as a lysosomal targeting signal through the binding of beta-COP in endosomes
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 Nef downregulates cell surface expression of CD4 in CEM Nef+ cells by promoting the accumulation of CD4 in an acidic early endosome
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: Deletion of the 19 N-terminal amino acids, including the myristoylation signal from HIV-1 Nef inhibits both MHC-I and CD4 downregulation while preserving most CTL, T-helper and B-cell epitopes
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: In adult HIV-1 Nef transgenic mice, CD4 downregulation is found in CD4- and CD8-double positive thymocytes; co-localization of CD4 with a Golgi-specific marker indicates Nef interferes with CD4 intracellular trafficking
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: Nef from primary isolates of HIV-1 suppresses surface CD4 expression in human and mouse T cells
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: Transduction of the HIV-1 nef gene into murine cells expressing human, chimpanzee, or murine CD4 induces cell surface downregulation of all three molecules; the cytoplasmic domain of CD4 is required for its downregulation by Nef
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: CD4 is downregulated by nef alleles isolated from peripheral blood leukocytes of HIV-1-infected individuals; Nef proteins with point mutations at positions Gly2, Asp36, Cys122, and Val148 exhibit different levels of CD4 downregulation
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 Nef mutants C142A and K158A/E160G exhibit a temperature-dependent ability to downregulate CD4
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: binds
Description: Yeast two-hybrid assays show that a nearly complete HIV-1 Nef protein is required for binding to the CD4 cytoplasmic domain (residues 394-416), and the dileucine motif in CD4 (residues 413-414) is essential for this direct interaction
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: binds
Description: Solution NMR spectroscopy studies show a 13 amino acid peptide (residues 407-419) derived from the CD4 cytoplasmic domain binds directly to HIV-1 Nef in a manner that involves amino acid residues 57-59, 95-97, 106, and 110 in Nef
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 Nef downregulates CD4 rapidly during the early phase of virus infection, whereas HIV-1 Vpu and Env function late in the infection; in primary cells, down-modulation of CD4 has a stronger dependence on Nef function for reducing cell surface CD4
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: A dileucine motif in the cytoplasmic domain of CD4 is involved in the association of CD4 with the tyrosine kinase Lck and the downregulation of CD4 by HIV-1 Nef, however Nef does not induce dissociation of Lck from CD4 in acutely HIV-infected cells
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: HIV-1 Nef downregulates CD4 expression on the surface of Jurkat cells and blocks the CD3 signaling pathway; mutations at amino acids 174 and 175 reduce the ability of Nef to downregulate CD4 expression
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: A dileucine motif in Nef is required for CD4 downregulation and for interaction with clathrin adaptor complexes AP-1 and AP-2, which are responsible for recruiting sorted proteins into clathrin-coated pits
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: An isoleucine residue at position 410 and two leucine residues at positions 413 and 414 in CD4 are required for HIV-1 Nef-mediated CD4 downregulation in cells
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: Two distinct regions within HIV-1 Nef, amino acid residues 96-144 and 175-186, are required for CD4 downregulation in cells
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC

HIV protein: Nef
Interaction type: downregulates
Description: Overexpression of Nef-associated factor 1, Naf1, increases cell surface CD4 expression; HIV-1 Nef suppresses this activity of Naf1 to downregulate CD4 expression
HIV protein sequence: MGGKWSKSSVIGWPTVRERMRRAEPAADRVGAASRDLEKHGAITSSNTAATNAACAWLEAQEEEEVGFPVTPQVPLRPMTYKAAVDLSHFLKEKGGLEGLIHSQRRQDILDLWIYHTQGYFPDWQNYTPGPGVRYPLTFGWCYKLVPVEPDKIEEANKGENTSLLHPVSLHGMDDPEREVLEWRFDSRLAFHHVARELHPEYFKNC