Epigenetics research addresses alterations to chromatin that propagate different patterns of transcription or gene expression and silencing.
The major components of chromatin are DNA and histone proteins. Two copies of each histone core protein (H2A, H2B, H3 & H4) are assembled into an octamer, wrapped around by DNA to form a nucleosome core. The nucleosome controls the accessibility of DNA to the transcription machinery and chromatin remodelling factors.
Chromatin immunoprecipitation (ChIP) is a method used to determine the location of genome binding sites for a specific protein of interest, giving invaluable insights into the regulation of gene expression. ChIP involved the selective enrichment of a chromatin fraction containing a specific antigen. Antibodies that recognize a specific protein or protein modification are used to determine the relative abundance of the antigen at specific loci.
ChIP-seq and ChIP-qPCR are techniques that allow the identification of protein-DNA binding sites.