{
  "id": 4706180,
  "title": "MORC and MOM1 spatially constrain RNA Polymerase V chromatin positioning to shape DNA methylation landscapes",
  "url": "https://urgent.news/2026/08/31/morc-and-mom1-spatially-constrain-rna-polymerase-v-chromatin",
  "topic": "science",
  "section": "Science",
  "published": "2026-08-31T00:00:00.000Z",
  "source": {
    "name": "bioRxiv",
    "slug": "biorxiv",
    "url": "https://www.biorxiv.org/content/10.64898/2026.08.30.748062v1?rss=1"
  },
  "original_language": "en",
  "account": "RNA Polymerase V (Pol V), a plant-specific enzyme, plays a crucial role in transcribing noncoding RNAs within the RNA-directed DNA methylation pathway. This process influences gene expression and genome stability by regulating de novo DNA methylation. Nonetheless, the precise mechanisms controlling Pol V chromatin localization and its transcriptional activities have remained unclear.\n\nIn a recent study, researchers discovered that Pol V localization is spatially constrained by two chromatin regulators: microrchidia (MORC) and MORPHEUS MOLECULE 1 (MOM1). Both MORC and MOM1 facilitate Pol V occupancy at sites near active chromatin. Conversely, the absence of these regulators causes Pol V to redistribute into CMT3-enriched heterochromatin, resulting in noncoding RNA transcription, small RNA production, and DNA methylation.\n\nThe researchers propose a combinatorial model in which recruitment, spatial constraint, and DNA methylation feedback work together to define Pol V chromatin distribution and its epigenetic functions. These findings shed light on the intricate mechanisms governing Pol V's role in regulating DNA methylation landscapes in plants.",
  "summary": "Plant-specific RNA Polymerase V (Pol V) transcribes noncoding RNAs in the RNA-directed DNA methylation pathway, thereby influencing gene expression and genome stability by controlling de novo DNA methylation. However, the mechanisms governing precise chromatin localization and transcriptional activities of Pol V remain elusive. Here we show that Pol V localization is spatially constrained by the…",
  "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."
}