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Ploidy-dependent changes in the epigenome of symbiotic cells correlate with specific patterns of gene expression.

ABSTRACT: The formation of symbiotic nodule cells in Medicago truncatula is driven by successive endoreduplication cycles and transcriptional reprogramming in different temporal waves including the activation of more than 600 cysteine-rich NCR genes expressed only in nodules. We show here that the transcriptional waves correlate with growing ploidy levels and have investigated how the epigenome changes during endoreduplication cycles. Differential DNA methylation was found in only a small subset of symbiotic nodule-specific genes, including more than half of the NCR genes, whereas in most genes DNA methylation was unaffected by the ploidy levels and was independent of the genes' active or repressed state. On the other hand, expression of nodule-specific genes correlated with ploidy-dependent opening of the chromatin as well as, in a subset of tested genes, with reduced H3K27me3 levels combined with enhanced H3K9ac levels. Our results suggest that endoreduplication-dependent epigenetic changes contribute to transcriptional reprogramming in the differentiation of symbiotic cells.

SUBMITTER: Nagymihaly M

PROVIDER: S-EPMC5410778 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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Ploidy-dependent changes in the epigenome of symbiotic cells correlate with specific patterns of gene expression.

Nagymihály Marianna M Veluchamy Alaguraj A Györgypál Zoltán Z Ariel Federico F Jégu Teddy T Benhamed Moussa M Szűcs Attila A Kereszt Attila A Mergaert Peter P Kondorosi Éva É

Proceedings of the National Academy of Sciences of the United States of America 20170412 17

The formation of symbiotic nodule cells in <i>Medicago truncatula</i> is driven by successive endoreduplication cycles and transcriptional reprogramming in different temporal waves including the activation of more than 600 cysteine-rich <i>NCR</i> genes expressed only in nodules. We show here that the transcriptional waves correlate with growing ploidy levels and have investigated how the epigenome changes during endoreduplication cycles. Differential DNA methylation was found in only a small su ...[more]

PMID: 28404731

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Ploidy-dependent changes in the epigenome of symbiotic cells correlate with specific patterns of gene expression.

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Ploidy-dependent changes in the epigenome of symbiotic cells correlate with specific patterns of gene expression.

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