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Archival chromatin sequencing in formalin-fixed mouse specimens

ABSTRACT: Formalin induces inter- and intra-molecular crosslinks within exposed cells. This cross-linking can be exploited to characterise chromatin state as in the FAIRE (Formaldehyde-Assisted Isolation of Regulatory Elements) and MNase (micrococcal nuclease) assays. Here, we optimised the FAIRE and MNase assays for application upon heavily-fixed tissues as is typically found in historical formalin-preserved museum specimens. We demonstrate these assays in formalin-fixed mouse specimens and compare the chromatin signatures to specimen-matched fresh tissues. We found that heavy formalin fixation modulates rather than eliminates signatures of differential chromatin accessibility and that these chromatin profiles are reproducible, tissue-specific and sex-specific in vertebrate specimens.

ORGANISM(S): Mus musculus

PROVIDER: GSE256158 | GEO | 2024/03/01

REPOSITORIES: GEO

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Archival chromatin sequencing in formalin-fixed mouse specimens [FAIRE and Mnase]

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