Epigenetic reprogramming rewires transcription during the alternation of generations in Arabidopsis

• Published in: eLife Vol. 10
• Main Authors: Borg, Michael, Papareddy, Ranjith K, Dombey, Rodolphe, Axelsson, Elin, Nodine, Michael D, Twell, David, Berger, Frédéric
• Format: Journal Article
• Language: English
• Published: England eLife Sciences Publications Ltd 25-01-2021; eLife Sciences Publications, Ltd
• Subjects: Algae; alternation of generations; Arabidopsis; Arabidopsis - genetics; Chromatin; Chromatin - metabolism; Datasets; Demethylation; Developmental Biology; Diploids; DNA methylation; Epigenesis, Genetic; epigenetic reprogramming; Epigenetics; Fertilization; Flowering; Gene expression; Gene Expression Regulation, Plant; Genomes; life cycle; Life cycles; Molecular modelling; Plant Biology; pollen; Population; Regulatory sequences; Sperm; Transcription; Transcription, Genetic; alternation of generations; life cycle; transcription; pollen; A. thaliana; developmental biology; epigenetic reprogramming; plant biology; chromatin
• ISSN: 2050-084X; 2050-084X
• DOI: 10.7554/elife.61894

Alternation between morphologically distinct haploid and diploid life forms is a defining feature of most plant and algal life cycles, yet the underlying molecular mechanisms that govern these transitions remain unclear. Here, we explore the dynamic relationship between chromatin accessibility and epigenetic modifications during life form transitions in Arabidopsis. The diploid-to-haploid life form transition is governed by the loss of H3K9me2 and DNA demethylation of transposon-associated
-regulatory elements. This event is associated with dramatic changes in chromatin accessibility and transcriptional reprogramming. In contrast, the global loss of H3K27me3 in the haploid form shapes a chromatin accessibility landscape that is poised to re-initiate the transition back to diploid life after fertilisation. Hence, distinct epigenetic reprogramming events rewire transcription through major reorganisation of the regulatory epigenome to guide the alternation of generations in flowering plants.