{"title":"The transcriptional repressors IAA5 and IAA29 participate in DNA damage-induced stem cell death in Arabidopsis roots.","authors":"Naoki Takahashi, Nobuo Ogita, Toshiya Koike, Kohei Nishimura, Soichi Inagaki, Ye Zhang, Takumi Higaki, Masaaki Umeda","doi":"10.1093/plphys/kiaf303","DOIUrl":null,"url":null,"abstract":"<p><p>Plants generate organs continuously during post-embryonic development. Thus, their ability to preserve stem cells in changing environments is crucial for their survival. Genotoxic stress threatens genome stability in all somatic cells. However, in the meristem, only the stem cells actively die in response to DNA damage, followed by stem cell replenishment that guarantees genome stability in these cells. Cytokinin biosynthesis-induced inhibition of downward auxin flow participates in DNA damage-induced stem cell death in roots. Without this system, stem cell death occurs at a reduced but significant level, suggesting another mechanism governing the DNA damage response in stem cells. Here, we demonstrate that in response to DNA double-strand breaks, the AUXIN/INDOLE-3-ACETIC ACID (Aux/IAA) family members IAA5 and IAA29, encoding negative regulators of auxin signaling, are induced in Arabidopsis (Arabidopsis thaliana) roots. The transcription factor SUPPRESSOR OF GAMMA RESPONSE 1 directly induces their expression as an active response to DNA damage. In the iaa5 iaa29 double mutant, DNA damage-induced stem cell death is greatly suppressed, while it is fully restored by the expression of a stable form of IAA5 in vascular stem cells. Our genetic data reveal that reduced auxin signaling around the stem cell niche, caused by IAA5 and IAA29 induction and enhanced cytokinin biosynthesis, is a prerequisite for cell death induction, thus playing a central role in maintaining genome integrity in root stem cells.</p>","PeriodicalId":20101,"journal":{"name":"Plant Physiology","volume":" ","pages":""},"PeriodicalIF":6.5000,"publicationDate":"2025-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Plant Physiology","FirstCategoryId":"99","ListUrlMain":"https://doi.org/10.1093/plphys/kiaf303","RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"PLANT SCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
Plants generate organs continuously during post-embryonic development. Thus, their ability to preserve stem cells in changing environments is crucial for their survival. Genotoxic stress threatens genome stability in all somatic cells. However, in the meristem, only the stem cells actively die in response to DNA damage, followed by stem cell replenishment that guarantees genome stability in these cells. Cytokinin biosynthesis-induced inhibition of downward auxin flow participates in DNA damage-induced stem cell death in roots. Without this system, stem cell death occurs at a reduced but significant level, suggesting another mechanism governing the DNA damage response in stem cells. Here, we demonstrate that in response to DNA double-strand breaks, the AUXIN/INDOLE-3-ACETIC ACID (Aux/IAA) family members IAA5 and IAA29, encoding negative regulators of auxin signaling, are induced in Arabidopsis (Arabidopsis thaliana) roots. The transcription factor SUPPRESSOR OF GAMMA RESPONSE 1 directly induces their expression as an active response to DNA damage. In the iaa5 iaa29 double mutant, DNA damage-induced stem cell death is greatly suppressed, while it is fully restored by the expression of a stable form of IAA5 in vascular stem cells. Our genetic data reveal that reduced auxin signaling around the stem cell niche, caused by IAA5 and IAA29 induction and enhanced cytokinin biosynthesis, is a prerequisite for cell death induction, thus playing a central role in maintaining genome integrity in root stem cells.
期刊介绍:
Plant Physiology® is a distinguished and highly respected journal with a rich history dating back to its establishment in 1926. It stands as a leading international publication in the field of plant biology, covering a comprehensive range of topics from the molecular and structural aspects of plant life to systems biology and ecophysiology. Recognized as the most highly cited journal in plant sciences, Plant Physiology® is a testament to its commitment to excellence and the dissemination of groundbreaking research.
As the official publication of the American Society of Plant Biologists, Plant Physiology® upholds rigorous peer-review standards, ensuring that the scientific community receives the highest quality research. The journal releases 12 issues annually, providing a steady stream of new findings and insights to its readership.