Chromatin Structure and Domains

Abstract

Abstract In the cell nucleus, deoxyribonucleic acid (DNA) is associated with nuclear proteins called histones to form chromatin. According to the type of factors that bind it, chromatin is organised into different subdomains. Chromatin structure is essential to compact DNA but it is also crucial for the proper development of multicellular organisms. Indeed, it is a highly organised structure through which, genetic material is modulated to regulate nuclear processes, including transcription, replication and DNA repair. It is notably regulated via reversible covalent histone modifications. These multiple modifications deposited on chromatin by different histone modifying enzymes, serve as specific recognition signal for DNA‐regulating proteins. More recently, spatial organisation of chromosomes in the nucleus has been identified as a critical feature for chromatin regulation, contributing in the fine tuning of transcription regulation, a major issue of cell differentiation and maintenance of cell identity during development. Key Concepts: Chromatin is a highly structured entity with an important flexibility. The large repertoire of epigenetic modifications offers a wide range of specific molecular and cellular responses. Together with genetic information, epigenetic marks play a critical role in the transmission of gene regulation. Nuclear organisation of chromosomes participates in the inheritance of chromatin states.