Discuss how can the cloning of linker histones help to understand Essay

Discuss how can the cloning of linker histones help to understand their function in cells - Essay Example Histones have a characteristic ‘histone fold domain’ consisting of structural motif known as ‘helix-turn-helix and that are three alpha helices that all connected by loops. Each of the histones fits perfectly with their counterpart to form heterodimer structures that assume the appearance of a hand-shake. The histone cell structures are buried inside the core structure of the nucleosome. The histones have conspicuous N-terminal tails protruding out of the compact structure. Often the terminal tails are subjected to several post-translational modification that include methylation, ubiquitination, acetylation, phosphorylation, and many more (Xie 2009). It is the combination of the marks they get through the modification processes, and that determine the factors that bind to the region of DNA and in the long run regulation the expression status of the given locus. The multiple loci occurring as distinct clusters on different chromosomes are where the histone genes typ ically transcribed. Histone proteins have their individual repertoire of variants distinct in the sequence of their amino acid mostly in the protruding N-terminal region. The expression of the variants, which is dependent on the type, can either be replication-dependent or replication-independent. As will be discussed in a dedicated section below, their main function is to mark specific regions of the DNA by replacing canonical histone from the nucleosomes present and the particular site. This stress on distinct regions in the genome has a noteworthy part in recruitment of diverse factors to that site occasioning differential treatment. It is this mechanism that lays the foundation for creation and development of an epigenetic ‘memory’. The dyad axis of symmetry that is where the exiting and the entering DNA duplexes cross has been a long held outlook of the most likely location for the binding of the linker histone to the nucleosome core particles. The high