{
  "id": 3306271,
  "title": "Expression of AAACTAC satellite repeats as a long noncoding RNA in the early oocyte of Drosophila virilis",
  "url": "https://urgent.news/2026/08/25/expression-of-aaactac-satellite-repeats-as-a-long-noncoding-rna-in",
  "topic": "science",
  "section": "Science",
  "published": "2026-08-25T00:00:00.000Z",
  "source": {
    "name": "bioRxiv",
    "slug": "biorxiv",
    "url": "https://www.biorxiv.org/content/10.64898/2026.08.24.746749v1?rss=1"
  },
  "original_language": "en",
  "account": "Satellite DNA, composed of repetitive DNA sequences often found near chromosome centromeres, has long been a subject of scientific debate regarding its function. These DNA arrays, typically located in heterochromatin, may surprise researchers by actually expressing long non-coding RNAs (lncRNAs). While a limited number of satellite lncRNAs have been characterized with purported functions, the extent and significance of satellite lncRNA involvement in developmental processes remains unclear. To gain insight into how prevalent and crucial satellite lncRNAs could be in developmental processes, researchers employed an evolutionary approach to study this phenomenon in Drosophila spp. ovaries. This tissue, well-characterized in terms of development yet only sparingly explored for satellite expression, provided an ideal setting for their investigation.\n\nUtilizing a publicly available total RNA-seq dataset, the team identified 118 out of 156 surveyed satellite DNAs expressed across ten species of Drosophila. Notably, 33 satellites displayed high expression, surpassing 20 RPM. However, the majority of these expressed satellites, except for two, exhibited higher read counts in a separate small RNA dataset. This observation suggests that most satellite transcripts likely serve as precursors for piRNA biogenesis, a process potentially unrelated to their initial expression. Among the two satellites that were expressed independently as lncRNAs, one, AAACTAC in D. virilis, stood out due to its highly strand-biased expression, with 96-97% of total reads originating from a single strand.\n\nFurther investigation via RNA FISH revealed the dynamic and spatially specific presence of the AAACTAC transcript within the oocyte nucleus, with peak expression observed during stages 3-5 of oocyte development. This pattern of expression was found to be conserved across three other species within the virilis clade that also contain this satellite DNA. Moreover, the study discovered expression of unrelated satellites in more distantly related D. borealis and littoralis species, both in the oocyte and nurse cells.\n\nThe findings of this study unveil a novel lncRNA, AAACUAC, found in the early oocyte nucleus. This lncRNA is conserved across roughly 5 million years of evolutionary history, positioning it as a promising candidate for uncovering the potential novel functions of satellite lncRNAs in the broader context of development.",
  "summary": "Satellite DNA is long arrays of tandem repetitive DNA located often near the centromeres of chromosomes, whose function, or lack of, has been debated since its discovery. Although situated in heterochromatin, satellite DNA may be expressed as long noncoding RNAs (lncRNAs). Although there are a few examples of satellite lncRNAs being characterized, and functions suggested, how widespread and…",
  "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."
}