Genetic and functional analysis of HIV type 1 nef gene derived from long-term nonprogressor children: association of attenuated variants with slow progression to pediatric AIDS. | LitMetric
Among persons infected by HIV-1, the rate of progression to AIDS is multifactorial being affected by host and viral factors, including the HIV-encoded negative factor (Nef). Our aim was to define whether variations in the nef gene as well as its functions may be associated with slower HIV disease course in infected children. The proviral HIV-1 nef gene was cloned, sequenced, and compared in children with contrasting disease course: 10 long-term nonprogressors (LTNP) and six rapid progressor (RP). The CD4 and MHC-I down-modulation ability of nef alleles derived from LTNP and RP children was analyzed. We observed that only one of our 10 LTNP had a protective genetic background, and out of them, 40% had defective nef genes, carrying substitutions at the (AWLEAQ(56-61)) and the (Rxx(22-24)) domains, and that those alleles were unable of down-regulate CD4 and MHC-I. The emergence or presence of Nef L58V substitution was associated with viral attenuation, indicated by a reduction in HIV viral loads, a persistent preservation of CD4(+) T cell counts, and lack of AIDS-related symptoms. Our results demonstrate that HIV-1 perinatally infected children carrying functionally defective nef HIV-1 strains have prolonged asymptomatic phases without therapy, suggesting a relevant role of CD4 and MHC-I down-modulation Nef domains on in vivo HIV-1 pathogenesis and pediatric immunodeficiency outcome.
The anti-WNT factor ZNRF3 is crucial for determining gonadal sex, as XY mice lacking it show variable ovarian tissue development during fetal stages.
Researchers used single-cell RNA sequencing to investigate how ZNRF3 deficiency affects cell development in the gonads, revealing failures in the proper differentiation of Sertoli and granulosa cells.
The study finds that without ZNRF3, there is significant disruption in the expected testicular cell fate, leading to a mix of cellular identities that complicate the traditional understanding of sexual differentiation.
In this study, we investigated the role of lncRNA-NEF in modulating hepatic stellate cell (HSC) activation, a key process in liver fibrosis. Using the GSE78160 dataset, we identified lncRNA-NEF as downregulated in liver cirrhosis patients. Gene Ontology and KEGG analyses implicated it in transcriptional regulation and cell cycle control.
HIV-1 Nef mediates immune evasion and viral pathogenesis in part through downregulation of cell surface cluster of differentiation 4 (CD4) and major histocompatibility complex class I (MHC-I) on infected cells. While Nef function of circulating viral populations found early in infection has been associated with reservoir size in early-treated cohorts, there is limited research on how its activity impacts reservoir size in people initiating treatment during chronic infection. In addition, there is little research on its role in persistence of viral variants during long-term antiretroviral therapy (ART).
* A study using murine models showed that the presence of the Nef protein in HIV increases neuroinflammation and damages brain structures compared to Nef-deficient strains.
* Findings suggest that Nef plays a key role in worsening neuronal injury and may guide future research on HAND mechanisms and treatments.
Introduction: HIV-1 non-structural proteins are promising targets for vaccine development and for creating approaches to personalized medicine. HIV-1 sub-subtype A6 has become the dominating strain in Russia. However, the geographic, economic and demographic characteristics of the country can contribute to the formation of differences between A6 variants circulating in different regions.
