{
  "id": 18107855,
  "title": "The intrinsically disordered N-terminal region of eIF5B nucleates RNA-driven phase separation",
  "url": "https://urgent.news/2026/11/04/the-intrinsically-disordered-n-terminal-region-of-eif5b-nucleates-rna",
  "topic": "science",
  "section": "Science",
  "published": "2026-11-04T00:00:00.000Z",
  "source": {
    "name": "bioRxiv",
    "slug": "biorxiv",
    "url": "https://www.biorxiv.org/content/10.64898/2026.11.02.763741v1?rss=1"
  },
  "original_language": "en",
  "account": "A recent study revealed that a specific region of the eukaryotic Initiation Factor 5B (eIF5B) protein, known as the N-terminal, is responsible for initiating an intracellular phenomenon called phase separation. This process is triggered by cellular stress and leads to an increase in alternative translation initiation. The eIF5B-NTR region plays a crucial role in the formation of cytoplasmic puncta, which are small, distinct structures within the cell.\n\nTo further investigate the driving force behind this phenomenon, researchers created a purified, binary, in vitro system to study the phase separation potential of the eIF5B-NTR. This system allowed them to demonstrate that the eIF5B-NTR forms RNA-driven condensates at normal physiological concentrations. Through their research, they were able to define the properties of these eIF5B condensates and the necessary amino acid sequence requirements for these polypeptides to form complex liquid-liquid condensates.\n\nA truncation mapping technique was employed by the researchers to identify a central arginine-rich core within the eIF5B-NTR region, which spans residues 200-400. This core is responsible for driving condensation, but it forms nearly static droplets when the rest of the polypeptide is absent. Finally, the researchers tested their model within cells to determine if the in vitro observations apply to the complex cellular environment.",
  "summary": "Recently, we found that eukaryotic Initiation Factor 5B (eIF5B) forms cytoplasmic puncta under conditions of cellular stress and that the puncta formation drives an increase in alternative translation initiation. The formation of these puncta depends on the intrinsically disordered N-terminal region of eIF5B (eIF5B-NTR). To address the driving force behind this observation, we reconstituted a…",
  "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."
}