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Purification of macroH2A.1 and macroH2A.2 Nucleosomes from Fetal Mouse Liver

ABSTRACT: MacroH2As core histone variants have a unique structure that includes C-terminal nonhistone domain. MacroH2As are highly conserved in vertebrates, and are thought to regulate gene expression. However the nature of genes regulated by macroH2As and the biological significance of macroH2As for the organism remain unclear. Our gene expression studies indicate that macroH2A.1 and macroH2A.2 work together to regulate specific genes. In these studies we examine the distributions of macroH2A.1 and macroH2A.2 nucleosomes to determine if they are localized to the genes that show altered expression in macroH2A knockout mouse liver.

ORGANISM(S): Mus musculus

PROVIDER: GSE57796 | GEO | 2014/10/15

SECONDARY ACCESSION(S): PRJNA248116

REPOSITORIES: GEO

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Purification of macroH2A.1 and macroH2A.2 Nucleosomes from Fetal Mouse Liver

Project description:MacroH2As core histone variants have a unique structure that includes C-terminal nonhistone domain. MacroH2As are highly conserved in vertebrates, and are thought to regulate gene expression. However the nature of genes regulated by macroH2As and the biological significance of macroH2As for the organism remain unclear. Our gene expression studies indicate that macroH2A.1 and macroH2A.2 work together to regulate specific genes. In these studies we examine the distributions of macroH2A.1 and macroH2A.2 nucleosomes to determine if they are localized to the genes that show altered expression in macroH2A knockout mouse liver. MacroH2A.1 and macroH2A.2 nucleosomes prepared from ~ 50 fetal mouse livers were purified by thio-affinity chromatography. Five samples were sequenced: Thiopropyl Sepharose, Normal Liver - contains mononucleosomal DNA from macroH2A.1-containing nucleosomes; Activate Thiol Sepharose, Normal Liver - contains mononucleosomal DNA primarily from macroH2A.2-containing nucleosomes. Starting Material, Normal Liver - this is a reference samplefor the first two samples. It contains mononucleosomal DNA from bulk fetal liver chromatin. Activated Thiol Sepharose, Knockout Livers - this is a control sample that contains mononucleosomal DNA from non-macroH2A nucleosomes that contaminate the macroH2A.2 nucleosomes. This fraction was prepared from macroH2A1/2 double knockout fetal livers; Starting Material, Knockout Liver - this is a reference sample for the fourth sample. It contains mononucleosomal DNA from bulk chromatin prepared from macroH2A1/2 double knockout fetal livers.

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