Selective Transcription of DNA Mediated by Nonhistone Proteins

Abstract

Publisher Summary This chapter discusses the regulatory role of the nonhistone proteins in both positive and negative control of gene activity. It determines the restrictive and stimulatory properties of those nonhistone proteins involved in specific transcription. It describes the purification of a near-homologous nonhistone protein that specifically inhibits transcription from DNA in a homologous RNA polymerase II system. The isolation of a nonhistone-protein fraction that selectively stimulates in vitro transcription from homologous DNA is also described in the chapter. The dependence of specific transcription from chromatin on the nonhistone chromosomal proteins, the high turnover rate of and the synthesis of unique nonhistone proteins in relation to cellular activity, and the tissue variations of these proteins, have led to the belief that the nonhistone proteins play a key role in the control of gene expression. The finding of a nonhistone protein that inhibits only reiterated sequences in DNA is not inconsistent with the multilevel control mechanism. Thus, the data presented in this chapter underlines the potential significance of the chromosomal proteins in both positive and negative control of gene expression.