The effects of supercoiling on the topoisomerization reaction by eukaryotic DNA topoisomerases I have been analyzed. The systems used were: DNA topoisomerase I from wheat germ, chicken erythrocyte and calf thymus on a 2.3 kb DNA fragment which encompasses the immunoglobulin kappa-light chain (L kappa) promoter of the mouse plasmacytoma MPC11; S. cerevisiae DNA topoisomerase I on a 2.2 kb DNA fragment from the same organism which encompasses the regulatory and the coding region of the ADH II gene; wheat germ DNA topoisomerase I on the plasmid pUC18. It was found in every system that lack of torsional stress prevents topoisomerization of the substrate. A simple regulatory model of DNA topoisomerase I function, based on topological considerations, is presented.
Eukaryotic DNA topoisomerase I reaction is topology dependent / Camilloni, Giorgio; DI MARTINO, E; Caserta, M; DI MAURO, Ernesto. - In: NUCLEIC ACIDS RESEARCH. - ISSN 0305-1048. - STAMPA. - 16:14 B(1988), pp. 7071-7085. [10.1093/nar/16.14.7071]
Eukaryotic DNA topoisomerase I reaction is topology dependent.
CAMILLONI, Giorgio;DI MAURO, Ernesto
1988
Abstract
The effects of supercoiling on the topoisomerization reaction by eukaryotic DNA topoisomerases I have been analyzed. The systems used were: DNA topoisomerase I from wheat germ, chicken erythrocyte and calf thymus on a 2.3 kb DNA fragment which encompasses the immunoglobulin kappa-light chain (L kappa) promoter of the mouse plasmacytoma MPC11; S. cerevisiae DNA topoisomerase I on a 2.2 kb DNA fragment from the same organism which encompasses the regulatory and the coding region of the ADH II gene; wheat germ DNA topoisomerase I on the plasmid pUC18. It was found in every system that lack of torsional stress prevents topoisomerization of the substrate. A simple regulatory model of DNA topoisomerase I function, based on topological considerations, is presented.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
