{
  "id": 6578614,
  "title": "Study answers long-debated structural question of primate cone photoreceptors",
  "url": "https://urgent.news/2026/09/10/study-answers-long-debated-structural-question-of-primate-cone",
  "topic": "science",
  "section": "Science",
  "published": "2026-09-10T11:20:01.000Z",
  "source": {
    "name": "Medical Xpress",
    "slug": "medical-xpress",
    "url": "https://medicalxpress.com/news/2026-09-debated-primate-cone-photoreceptors.html"
  },
  "original_language": "en",
  "account": "For over six decades, researchers have been uncertain about the structure of cone photoreceptors, the cells responsible for color vision in vertebrates. While nonmammalian species have clear evidence that cone disk membranes remain open to the extracellular space, the question remained unresolved for mammals, particularly primates. A new study led by Dr. David S. Williams from UCLA and his collaborators from UCSB and Harvard sheds light on this long-debated issue.\n\nThe team investigated the structure of cone photoreceptor disk membranes in rhesus macaques, a type of primate, by employing two techniques: electron tomography and electrophysiology. These methods allowed the researchers to measure and analyze the membranes in unprecedented detail. Their findings, published in the Journal of Neuroscience, reveal that the majority of cone disk membranes in primate species are closed structures, similar to those found in rod photoreceptors.\n\nThis discovery provides a more comprehensive understanding of the relationship between the structure and function of cone photoreceptors. The results suggest that the closed membrane configuration in primate cones has implications for processes such as membrane renewal and the overall mechanism of phototransduction, which is crucial for vision. The study not only resolves a long-standing structural question in primate vision but also opens new avenues for research into the cellular biology and physiology of phototransduction in primates, including humans.",
  "summary": "For more than 60 years, scientists have debated a basic structural question about cone photoreceptors, the cells that let vertebrates see color: Are their light-sensing disk membranes closed off inside the cell, or are they open to the extracellular space?",
  "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."
}