Dark-Induced Senescence Causes Localized Changes in DNA Methylation.
Plant Physiol
; 182(2): 949-961, 2020 02.
Article
in En
| MEDLINE
| ID: mdl-31792150
ABSTRACT
Senescence occurs in a programmed manner to dismantle the vegetative tissues and redirect nutrients towards metabolic pathways supporting reproductive success. External factors can trigger the senescence program as an adaptive strategy, indicating that this terminal program is controlled at different levels. It has been proposed that epigenetic factors accompany the reprogramming of the senescent genome; however, the mechanism and extent of this reprogramming remain unknown. Using bisulphite conversion followed by sequencing, we assessed changes in the methylome of senescent Arabidopsis (Arabidopsis thaliana) leaves induced by darkness and monitored their effect on gene and transposable element (TE) expression with transcriptome sequencing. Upon dark-induced senescence, genes controlling chromatin silencing were collectively down-regulated. As a consequence, the silencing of TEs was impaired, causing in particular young TEs to become preferentially reactivated. In parallel, heterochromatin at chromocenters was decondensed. Despite the disruption of the chromatin maintenance network, the global DNA methylation landscape remained highly stable, with localized changes mainly restricted to CHH methylation. Together, our data show that the terminal stage of plant life is accompanied by global changes in chromatin structure but only localized changes in DNA methylation, adding another example of the dynamics of DNA methylation during plant development.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
DNA Transposable Elements
/
Heterochromatin
/
Cellular Senescence
/
Arabidopsis
/
Plant Leaves
/
DNA Methylation
Type of study:
Etiology_studies
Language:
En
Journal:
Plant Physiol
Year:
2020
Document type:
Article
Affiliation country:
Sweden