{
  "id": 9487121,
  "title": "A naturally occurring Tat R52W variant in brain-derived HIV attenuates transcription and may contribute to reservoir persistence",
  "url": "https://urgent.news/2026/09/23/a-naturally-occurring-tat-r52w-variant-in-brain-derived-hiv",
  "topic": "health",
  "section": "Health & Medicine",
  "published": "2026-09-23T00:00:00.000Z",
  "source": {
    "name": "bioRxiv",
    "slug": "biorxiv",
    "url": "https://www.biorxiv.org/content/10.64898/2026.09.22.753475v1?rss=1"
  },
  "original_language": "en",
  "account": "HIV-1 maintains a presence even with suppressive antiretroviral therapy (ART), but the role of natural genetic variation in viral transcription regulation has not been fully explored. Researchers have now discovered a naturally occurring HIV-1 variant, known as Tat R52W, that dampens viral transcription by interfering with the interaction between the Tat protein and TAR RNA. Full-length HIV-1 genomes from brain microglia of a Last Gift donor, as well as peripheral viral sequences during ART, showed the presence of the R52W variant. This same variant was also found in another ART-suppressed donor within the same study group. A broader analysis of 3,440 clinical blood isolates from HIV-positive individuals revealed the R52W variant in 73 sequences (2.12%), including three individuals on ART and a therapy controller, across various viral subtypes. Structural analysis demonstrated that the R52W variant weakens the binding between Tat and TAR, while functional tests revealed significantly reduced Tat-mediated transcriptional activity. This activity could be restored by reverting the R52W variant back to its original state (W52R). These findings establish a direct molecular mechanism by which a naturally occurring HIV-1 variant influences viral transcriptional output. The study identifies transcriptionally attenuated HIV-1 variants in treated individuals and suggests that modulating Tat-dependent transcription could be an underrecognized factor contributing to viral persistence despite ART.",
  "summary": "HIV-1 persistence under suppressive antiretroviral therapy (ART) remains a major barrier to eradication, yet the contribution of naturally occurring viral variation to transcriptional regulation is incompletely understood. Here, we identify an HIV-1 Tat variant (R52W) that attenuates viral transcription through the disruption of the Tat-TAR RNA interaction. Full-length HIV-1 genomes derived from…",
  "key_points": [],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}