Three main epigenetic mechanisms are crucial in the regulation of gene expression:
1. DNA Methylation: The addition of methyl groups to DNA, typically at CpG islands, which can silence gene expression. 2. Histone Modification: Post-translational modifications of histone proteins, such as acetylation and methylation, that can either activate or repress transcription. 3. Non-coding RNAs: RNA molecules that do not code for proteins but can regulate gene expression at multiple levels, including microRNAs and long non-coding RNAs.
