ID 56412
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Takami, Tsuneaki Institute of Plant Science and Resources, Okayama University
Ohnishi, Norikazu Institute of Plant Science and Resources, Okayama University
Kurita, Yuko Faculty of Agriculture, Ryukoku University
Iwamura, Shoko Department of Biology, Graduate School of Science, Kobe University
Ohnishi, Miwa Department of Biology, Graduate School of Science, Kobe University
Kusaba, Makoto Graduate School of Science, Hiroshima University
Mimura, Tetsuro Department of Biology, Graduate School of Science, Kobe University
Sakamoto, Wataru Institute of Plant Science and Resources, Okayama University
Abstract
Mitochondria and chloroplasts (plastids) both harbour extranuclear DNA that originates from the ancestral endosymbiotic bacteria. These organelle DNAs (orgDNAs) encode limited genetic information but are highly abundant, with multiple copies in vegetative tissues, such as mature leaves. Abundant orgDNA constitutes a substantial pool of organic phosphate along with RNA in chloroplasts, which could potentially contribute to phosphate recycling when it is degraded and relocated. However, whether orgDNA is degraded nucleolytically in leaves remains unclear. In this study, we revealed the prevailing mechanism in which organelle exonuclease DPD1 degrades abundant orgDNA during leaf senescence. The DPD1 degradation system is conserved in seed plants and, more remarkably, we found that it was correlated with the efficient use of phosphate when plants were exposed to nutrient-deficient conditions. The loss of DPD1 compromised both the relocation of phosphorus to upper tissues and the response to phosphate starvation, resulting in reduced plant fitness. Our findings highlighted that DNA is also an internal phosphate-rich reservoir retained in organelles since their endosymbiotic origin.
Note
This is an Accepted Manuscript of an article published by Springer Nature Publishing AG
Published Date
2018-05-12
Publication Title
Nature Plants
Volume
volume4
Publisher
Springer Nature Publishing AG
Start Page
1044
End Page
1055
ISSN
20550278
NCID
AA1273934X
Content Type
Journal Article
language
英語
OAI-PMH Set
岡山大学
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author
PubMed ID
DOI
Related Url
isVersionOf https://doi.org/10.1038/s41477-018-0291-x