HDACs are enzymes found in eukaryotes. It removes the acetyl group from the lysine residue on the N-terminal regions of histone proteins and the process is called histone deacetylation. It results in the increased positive charge on histones. The DNA possesses negatively charged sugar-phosphate backbone; therefore the positively charged histones bind more firmly to the DNA. This makes the DNA unavailable for the transcription
factors and eventually leads to the gene silencing. Rather than histone proteins, HDACs ...
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