Nucleosome

Histones are crucial proteins around which DNA wraps to form nucleosomes, the fundamental units of chromatin structure in eukaryotic cells. This packaging allows the long DNA molecules to be compacted and fit within the cell nucleus. Histones play a pivotal role in regulating gene expression, as their chemical modifications can either promote or inhibit the accessibility of DNA to transcription factors and other regulatory proteins. By modulating the chromatin structure, histones influence vario