Nedd4-Mediated Increase in HIV-1 Gag and Env Proteins and Immunity following DNA-Vaccination of BALB/c Mice

Abstract

The late assembly domain of many viruses is critical for budding. Within these domains, encoded in viral structural proteins, are the conserved motifs PTAP, PPxY and YPxL. These sequences are the key determinants for association of viral proteins with intracellular molecules such as Tsg101, Nedd4 and AIP1/ALIX. While roles for Tsg101 and AIP1/ALIX in HIV-1 budding have been well established, less is known about the role of Nedd4. Recent studies, however, have identified a function for Nedd4-like protein in HIV-1 release. In this study, we investigated post-transcriptional changes of Nedd4 following SHIVSF162P3 infection of rhesus macaques, its role on HIV-1 p24 and gp120 levels in vitro and its potential as an immune modulator in HIV vaccination of BALB/c mice. Increased Nedd4 protein levels were noted in both CD4+ and CD8+ T cells following SHIVSF162P3-infection of naïve macaques. Transient co-transfection studies in 293 cells with HXB2 and Nedd4 demonstrated a Nedd4-mediated increase in p24 and gp120 levels. This increase was found to be dependent on the Ca2+/calmodulin-regulated phospholipid binding C2 domain and not ubiquitin ligase activity or HIV LTR activity. Co-transfection of Nedd4 with plasmid DNA expressing Gag or Env was further shown to augment both intracellular and extracellular Gag or Env proteins. To assess the potential of Nedd4 as an immune modulator, BALB/c mice were immunized intramuscularly with plasmid DNA encoding HIV gag, env and Nedd4. Nedd4 co-administration was found to increase serum anti-p24 but not anti-gp120 antibodies. Nedd4 co-injection was found to have no affect on Gag- or Env-specific IFNγ but had a trend of increased Gag-specific IL-6, IL-17A and TNFα that was not seen following Env stimulation. Based on our initial findings, Nedd4-mediated changes in HIV protein levels and its potential use in HIV-1 vaccine development warrants further investigation.

Modular mimicry and engagement of the Hippo pathway by Marburg virus VP40: Implications for filovirus biology and budding

“…For example, the well-described PPxY L-domain motif mediates the recruitment of a series of host HECT-family E3 ubiquitin ligases via one or more of their cognate WW-domains to facilitate egress [9,10,[14][15][16][17][18][19][20]. In general, viral PPxY/WWdomain interactions involving host E3 ligases are believed to promote mono-ubiquitinylation of the viral matrix proteins [11][12][13][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38][39], which allows the viral matrix protein to engage the ESCRT machinery to facilitate virus-cell separation at the plasma membrane [5,7,[11][12][13]21,[23][24][25][26][27]31,[35][36][37][38]…”

Ubiquitin Ligase WWP1 Interacts with Ebola Virus VP40 To Regulate Egress

“…For example, the eVP40 PPXY L-domain motif interacts with HECT family E3 ubiquitin (Ub) ligases Nedd4 (1,6,13,(16)(17)(18)(19)(20) and Itch (21), as well as the cytoskeletal remodeling protein IQGAP1 (12). In general, these virus-host interactions are advantageous for efficient virus production (1,14,15,18,19,(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34)(35)(36)(37)(38). The eVP40 PPXY core motif recruits host proteins by interacting specifically with one or more of their modular WW domains (39)(40)(41)(42)(43)(44)(45)(46)(47).…”

Construção e caracterização imunológica de formulação vacinal com propriedade profiláticas voltada para o controle do vírus da imunodeficiência humana (HIV) e do vírus herpes (HSV).

“…A -O envelope viral apresenta complexos triméricos gp120-gp41 embebidos na membrana; A proteína transmembrana gp41 interage com a matriz (formada pela proteína p17 -em azul claro); O capsídeo (formada pela proteína p24 -em azul escuro) compõe um núcleo no formato de cone que abriga o genoma do HIV-1, que é composto por duas moléculas de RNA fita positiva; O genoma está envolvido pelas proteínas p7/p6 do nucleocapsídeo (em amarelo). B -O genoma do HIV-1 é composto pelos nove genes : gag, env, pol, tat, rev, vpu, vif, vpr (KULKARNI et al, 2013;LEWIS et al, 2014) e em estratégias com células dendríticas (DC) (IDOYAGA et al, 2011;TRUMPFHELLER et al, 2006).…”