{
  "id": 3051854,
  "title": "Repeated UV-C exposure alters gibberellin homeostasis and inhibits growth in Arabidopsis thaliana",
  "url": "https://urgent.news/2026/08/24/repeated-uv-c-exposure-alters-gibberellin-homeostasis-and-inhibits",
  "topic": "science",
  "section": "Science",
  "published": "2026-08-24T00:00:00.000Z",
  "source": {
    "name": "bioRxiv",
    "slug": "biorxiv",
    "url": "https://www.biorxiv.org/content/10.64898/2026.08.22.746412v1?rss=1"
  },
  "original_language": "en",
  "account": "Repeated exposure to ultraviolet-C (UV-C) radiation can negatively impact plant growth, particularly in Arabidopsis thaliana, a widely studied model organism. A recent study reveals that short daily UV-C pulse treatments, lasting only 12 seconds and delivering 1,200 J m-2, lead to reduced plant height and delayed flowering in Arabidopsis thaliana. This study also uncovers significant alterations in gibberellin (GA) homeostasis following UV-C exposure.\n\nThe research demonstrates that UV-C treatment results in decreased levels of GA biosynthesis precursors, including GA12, GA53, GA15, and GA24, as well as the bioactive GA4. Additionally, catabolites such as GA34 and GA110 are also lower in plants exposed to UV-C compared to untreated controls. These changes are accompanied by reduced transcript levels of key GA biosynthesis genes (KS, GA13ox1, GA20ox1, and GA3ox1), alongside opposing changes in the expression of GA2ox genes.\n\nInterestingly, the study findings indicate that providing exogenous GA4 restores growth in UV-C-treated plants, suggesting that reduced GA availability contributes to the inhibitory effects of UV-C radiation. Furthermore, the study reveals that certain GA-signalling mutants, such as gdella, and GA-biosynthesis mutants (kao1 and kao2), exhibit significantly reduced UV-C responses. This observation underscores the crucial role of GA metabolism and signaling in the developmental response to repeated UV-C exposure.\n\nMoreover, the dynamics of UV-C-induced hormonal responses seem to be influenced by the exposure regimen. In conclusion, these findings emphasize the importance of understanding how GA metabolism and signaling pathways are involved in the plant's response to repeated UV-C exposure and suggest that the timing and frequency of UV-C exposure play a significant role in shaping the hormonal changes observed in Arabidopsis thaliana.",
  "summary": "Ultraviolet-C (UV-C) radiation can be highly damaging to plants, yet its effects on gibberellin (GA) homeostasis are not well understood. In this study, we show that short daily UV-C pulse treatments (12 s, 1,200 J m-2) applied for seven days reduce plant height and delay flowering in Arabidopsis thaliana. Endogenous levels of the GA biosynthesis precursors GA12, GA53, GA15, and GA24, 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."
}