Nucleosome and chromatin structures and functions.

Abstract

From the above discussion it can be appreciated that the major unknowns to advancing our understanding of nucleosome and chromatin structure and functions are: 1) the binding sites of the histone N- and C-terminal domains in native nucleosomes and in chromatin; 2) the effects of histone reversible chemical modifications of phosphorylations, acetylations and ubiquitinations on the binding of the histone N- and C-terminal domains in nucleosome and chromatin structures; 3) the path(s) of the linker DNA between nucleosome in the different orders of chromatin structure; 4) the position of the globular, N- and C-terminal domains of linker histones in the nucleosome and chromatin structures; and 5) the lack of a detailed structure for the 30 nm chromatin fiber. The above unknowns provide formidable challenges for future researchers.