Temperature-dependent fasciation mutants provide a link between mitochondrial RNA processing and lateral root morphogenesis
- The University of Tokyo, Japan
- Tokyo Metropolitan University, Japan
- Shimane University, Japan
- Tokyo University of Pharmacy and Life Sciences, Japan
- National Institute for Basic Biology, Japan
- Kyushu University, Japan
- Ehime University, Japan
- Okayama University, Japan
Abstract
Although mechanisms that activate organogenesis in plants are well established, much less is known about the subsequent fine-tuning of cell proliferation, which is crucial for creating properly structured and sized organs. Here we show, through analysis of temperature-dependent fasciation (TDF) mutants of Arabidopsis, root redifferentiation defective 1 (rrd1), rrd2, and root initiation defective 4 (rid4), that mitochondrial RNA processing is required for limiting cell division during early lateral root (LR) organogenesis. These mutants formed abnormally broadened (i.e., fasciated) LRs under high-temperature conditions due to extra cell division. All TDF proteins localized to mitochondria, where they were found to participate in RNA processing: RRD1 in mRNA deadenylation, and RRD2 and RID4 in mRNA editing. Further analysis suggested that LR fasciation in the TDF mutants is triggered by reactive oxygen species generation caused by defective mitochondrial respiration. Our findings provide novel clues for the physiological significance of mitochondrial activities in plant organogenesis.
Data availability
The microarray data has been deposited in the Gene Expression Omnibus (http://www.ncbi.nlm.nih.gov/geo/) under accession number GSE34595. All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials.
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Transcript profile changes associated with lateral root fasciation in temperature-sensitive mutantsNCBI Gene Expression Omnibus, GSE34595.
Article and author information
Author details
Funding
Japan Society for the Promotion of Science (Grants-in-Aid for JSPS Fellows (No. 09J08676))
- Kurataka Otsuka
Japan Society for the Promotion of Science London (Grants-in-Aid for JSPS Fellows (No. 17J05722))
- Akihito Mamiya
Ministry of Education, Culture, Sports, Science and Technology (Graduate Program for Leaders in Life Innovation (GPLLI))
- Akihito Mamiya
Ministry of Education, Culture, Sports, Science and Technology (Grant-in-Aid for Scientific Research on Priority Areas (No. 19060001))
- Munetaka Sugiyama
Japan Society for the Promotion of Science (Grant-in-Aid for Scientific Research (B) (No. 25291057))
- Munetaka Sugiyama
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Copyright
© 2021, Otsuka et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Temperature-dependent fasciation mutants provide a link between mitochondrial RNA processing and lateral root morphogenesis
eLife 10:e61611.
https://doi.org/10.7554/eLife.61611
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