Faculty Collaboration Database

In vitro studies on the maintenance of transcription-induced stress by histones and polyamines. J Biol Chem 2000 Jan 07;275(1):657-68

Date

01/05/2000

Pubmed ID

10617664

DOI

10.1074/jbc.275.1.657

Scopus ID

2-s2.0-0039765281 (requires institutional sign-in at Scopus site)   32 Citations

Abstract

Several factors were evaluated to determine their role in facilitating the presence of transcription-induced stresses in a circular DNA. Transcription was done with T7 RNA polymerase in the presence of E. coli topoisomerase I and closed circular DNA. Positive stress was observed in hypotonic conditions or when one of the polyamines, spermidine or spermine, were present. Polycations such as polylysine, polyarginine, histone H1, histones H2A-H2B, and protamine were observed to induce minimal positive stress. It is known that polyamines influence DNA structure by causing both self-association and sequence-specific structural alterations (polyamine-induced localized bending). Experimental evidence indicates that the likely cause of the positive stress is the induced bending. In order to evaluate protein-mediated bending, transcription was done on nucleosomes. A minimum of three nucleosomes on a DNA of 6055 bp was sufficient to generate very high levels of positive stress. Histones H3-H4 in the absence of H2A-H2B were responsible for this effect. Since these histones by themselves are able to maintain negative coils on DNA, it is concluded that protein-mediated bending is yet another mechanism for placing rotational restriction on DNA. The bending of DNA by either polyamines or histones is an effective mechanism for promoting transcription-induced stresses at physiological ionic strength.

Author List

Peng HF, Jackson V

Author

Vaughn Jackson PhD Emeritus Professor in the Biochemistry department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Chickens
DNA Topoisomerases, Type I
DNA, Circular
DNA-Directed RNA Polymerases
Histones
Motion
Nucleic Acid Conformation
Pliability
Polyamines
RNA
Stress, Mechanical
Transcription, Genetic
Viral Proteins