Project description: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.
Project description:Metriaclima estherae, Protomelas similis, Rhamphochromis "chilingali", and Astatotilapia tweddlei genomic DNA hybridized with Astatotilapia burtoni genomic DNA
Project description:One tooth of a lamprey and one piece of trunc skin was lysed and analysed for its protein content. The samples were generously provided by the Museum of Natural History Vienna. The samples were stored in ethanol and the origin of the specimen is not known.
Project description:Metriaclima estherae, Protomelas similis, Rhamphochromis "chilingali", and Astatotilapia tweddlei genomic DNA hybridized with Astatotilapia burtoni genomic DNA 2 Metriaclima estherae vs Astatotilapia burtoni, 2 Protomelas similis vs Astatotilapia burtoni, 2 Rhamphochromis "chilingali" vs Astatotilapia burtoni, and 2 Astatotilapia tweddlei vs Astatotilapia burtoni hybs, all in balanced dye swaps
Project description: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.