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Pierre Bourguet

@p-bourguet.bsky.social

687 followers 409 following 36 posts

Biologist studying transposons, gene regulation and chromatin in the Jullien group. Postdoc @ibmp-cnrs.bsky.social (Strasbourg, France).

Posts Replies Media

Pierre Bourguet @p-bourguet.bsky.social · 02/12/2025

Congratulations the first story from your lab Marco! To all co-authors and to Gesa for the stunning pictures 😍

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Pierre Bourguet @p-bourguet.bsky.social · 07/11/2025

To conclude, we propose a model of epigenetic inheritance where DDM1 functions are temporally separated during DNA replication, and CDCA7 predominantly promotes mCG maintenance, with minimal contribution to other DDM1 functions.

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Pierre Bourguet @p-bourguet.bsky.social · 07/11/2025

The worldwide distribution of CDCA7α alleles suggests it may contribute to local adaptation. We found these alleles correlate with an altitudinal cline in the mountains of Spain and are associated with changes in seed size, an adaptive trait for plants.

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Pierre Bourguet @p-bourguet.bsky.social · 07/11/2025

In natural populations, a 26-bp indel in the CDCA7α promoter acts as a rheostat, tuning its expression. This polymorphism affects the level of CG methylation and transposon silencing across the entire genome.

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Pierre Bourguet @p-bourguet.bsky.social · 07/11/2025

Quantitatively, CDCA7 disproportionately impacts mCG, indicating the predominant function of CDCA7 is to promote DDM1-dependent mCG. An important detail here is that we used ratios of mutant / WT to objectively compare methylation contexts.

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Pierre Bourguet @p-bourguet.bsky.social · 07/11/2025

We also mapped the physical interaction, showing the N-terminal domain of CDCA7α binds directly to the H2A.W-binding domain of DDM1.

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Pierre Bourguet @p-bourguet.bsky.social · 07/11/2025

The absence of CDCA7 has a weaker impact than DDM1 mutations, showing DDM1 can partially act without CDCA7. Conversely, we provide lots of genetic evidence that CDCA7 function exclusively through the DDM1 pathway.

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Pierre Bourguet @p-bourguet.bsky.social · 07/11/2025

We show that two A. thaliana genes, CDCA7α and CDCA7ß, redundantly contribute to all known DDM1 functions in heterochromatin maintenance. cdca7α/ß mutants phenocopy ddm1 mutants, affecting DNA methylation, histone variants and PTMs.

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Pierre Bourguet @p-bourguet.bsky.social · 07/11/2025

Using CG methylation (mCG) of heterochromatic transposons as a trait for GWAS, we identified a major genetic association to an uncharacterized gene: a plant ortholog of vertebrate CDCA7.

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