ABSTRACT
This chapter considers the involvement of nonhistone proteins in the regulation of gene expression with emphasis on a possible role for a subset of these complex and heterogeneous macromolecules at the nuclear and/or transcriptional level. Quantitative variations in the nonhistone chromosomal protein content of active and inactive tissues suggest that chromatin template activity is influenced by the nonhistone chromosomal proteins. A regulatory role for components of the nonhistone chromosomal proteins is suggested by changes in these macromolecules that are associated with modifications of gene expression in a number of biological situations. Nonhistone chromosomal proteins also seem to be involved in mediating viral-induced modifications in gene expression. One aspect of nonhistone chromosomal protein metabolism that may play an important role in the control of gene expression is their rapid phosphorylation and de-phosphorylation. The specific nonhistone chromosomal proteins responsible for rendering particular genetic sequences transcribable must be identified.
