Abstract:
The eukaryotic genome is packaged into the specialized organelle, the nucleus. The
enormous size of DNA poses a major challenge to be accommodated inside the nuclear
space. Within the nucleus, the DNA is packaged with basic proteins called histones to form
chromatin. The wrapping of DNA around the histones contributes to the efficient
condensation of the genetic material. However, compaction of DNA makes it inaccessible to
DNA regulatory elements. Thus, chromatin has been evolved as a dynamic structure with
different degrees of condensation. The structural plasticity of chromatin plays a key role in
regulating global gene expression. Specific chromatin structure regulates the accessibility
of binding of transcription factors and regulatory elements thereby controlling the DNA
dependent basic processes such as transcription, DNA replication, DNA recombination and
repair. Besides, the genetic information within the DNA is laden with various chemical
modifications of DNA bases and histone tails at specific genomic locations conferring to the
dynamic nature of chromatin.
