Final answer:
Chromatin remodelers reorganize nucleosomes by moving them using ATP, which affects gene expression. Chromatin modifiers add chemical groups to histones and DNA, leading to changes in chromatin structure. These alterations influence whether a gene is active or silenced, playing a critical role in epigenetic regulation.
Step-by-step explanation:
Chromatin remodelers reorganize nucleosomes by moving, sliding, and repositioning them. This process utilizes energy derived from the hydrolysis of ATP. Nucleosome reorganization is critical for various cellular processes and is associated with gene expression regulation.
Chromatin modifiers, on the other hand, add chemical groups to the histone proteins and DNA, such as methyl or acetyl groups. These modifications can lead to a more open chromatin structure, facilitating gene transcription, or a more closed structure, leading to gene silencing. Specific patterns of methylation, for example, have been identified as markers in multiple cancer types.
Changes in nucleosome positioning caused by chromatin remodeling complexes, and the chemical modifications introduced by chromatin modifiers, play a fundamental role in epigenetic regulation. They dynamically alter the accessibility of DNA to transcription machinery, thus playing a crucial role in the control of gene expression.