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Published on: September 17, 2016
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Epimutations Define a Fast-Ticking Molecular Clock in Plants
Nan Yao1, Robert J Schmitz2, Frank Johannes3
1Department of Genetics, University of Georgia, Athens, GA, USA.
Trends in Genetics : TIG
|May 21, 2021
Summary
Spontaneous DNA methylation changes, or epimutations, in plants are highly frequent and predictable. Their unique characteristics suggest epimutations can serve as a novel molecular clock for evolutionary and age-dating studies.
Area of Science:
- Epigenetics
- Plant Genomics
- Evolutionary Biology
Background:
- DNA methylation at CG dinucleotides occurs frequently in plants via spontaneous epimutations.
- These epimutations are 100,000 times more frequent than genetic mutations.
- Epimutations are effectively neutral and stably inherited through cell divisions.
Purpose of the Study:
- To propose epimutations as a novel molecular clock.
- To leverage the high rate and neutrality of epimutations for evolutionary timing.
- To enable age dating of long-lived perennial plants.
Main Methods:
- Mathematical modeling of epimutation accumulation.
- Analysis of epimutation rates and inheritance patterns.
- Application of epimutation dynamics to evolutionary and aging studies.
Main Results:
- Epimutations are a highly predictable epigenetic phenomenon in plants.
- The high rate and neutrality of epimutations are key characteristics.
- Mathematical models accurately describe epimutation accumulation over time.
Conclusions:
- Epimutations represent a powerful new molecular clock.
- This clock can be used for timing recent evolutionary events.
- Epimutations facilitate age dating of long-lived perennials like trees.
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