{
  "id": 7433563,
  "title": "Enhancer Tuning by Sequence-Specific Repressors",
  "url": "https://urgent.news/2026/09/14/enhancer-tuning-by-sequence-specific-repressors",
  "topic": "science",
  "section": "Science",
  "published": "2026-09-14T00:00:00.000Z",
  "source": {
    "name": "bioRxiv",
    "slug": "biorxiv",
    "url": "https://www.biorxiv.org/content/10.64898/2026.09.11.751074v1?rss=1"
  },
  "original_language": "en",
  "account": "Enhancers regulate the expression of genes by controlling the activity of transcription factors (TFs). To fine-tune their activity, enhancers require calibration, which is achieved by sequence-specific repressors. In a study focusing on human neural crest cells, researchers demonstrated that repressors SNAI1 and SNAI2 modulate enhancer activity quantitatively.\n\nThe presence of SNAI1/2 in a subset of active enhancers leads to an increase in H3K27ac, chromatin accessibility, and enhancer regulatory potential upon their depletion. The study also reveals that changes in SNAI1/2 binding motifs contribute to enhancer divergence between human and chimpanzee species, suggesting that these repressors play an evolutionary role in the tuning of enhancer activity.\n\nUsing single-molecule chromatin profiling through Deaminase-Assisted Fiber-seq (DAF-seq), the researchers observed that individual enhancers switch between open and nucleosome-dense chromatin states. While transcriptional activators favor the open chromatin states, SNAI1/2 shift the equilibrium towards nucleosome-occupied states. This mechanism impedes the binding of activator TFs without fully repressing the enhancer.\n\nThe researchers propose that SNAI1/2 function as a molecular dimmer switch, modulating nucleosome dynamics to accurately calibrate enhancer output.",
  "summary": "Enhancers integrate combinatorial inputs from sequence-specific transcription factors (TFs) and their activity must be calibrated to achieve precise spatiotemporal control of transcript dosage. Here we demonstrate that the sequence-specific repressors SNAI1 and SNAI2 (i.e. SNAIL and SLUG) quantitatively tune enhancer activity. In human neural crest cells, SNAI1/2 occupy a subset of active…",
  "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."
}