S1 nuclease recognizes DNA conformational junctions between left-handed helical (dT-dG n. dC-dA)n and contiguous right-handed sequences.
Year: 1984
Type: article
Abstract: The ability of negative supercoiling to induce a left-handed helix in the recombinant plasmid pRW777, which contains a tract of 64 base pairs of almost perfect (dT-dG) . (dC-dA) from the mouse kappa immunoglobin gene, was studied. S1 nuclease recognizes and cleaves within the junction region which must exist adjacent to the (dT-dG)n . (dC-dA)n tract when in a left-handed state. The cleavage pattern indicates conformational flexibility and structural differences between the two existing junctions. The 64-base pair alternating copolymer undergoes the supercoil-induced formation of a left-handed state over the superhelical density range of -0.04 to -0.06, indicating that (dT-dG)n . (dC-dA) sequences form a left-handed helix less readily than (dC-dG)n . (dC-dG)n sequences of equivalent length. However, these supercoil densities are within the range found in vivo. Supercoil relaxation and antibody binding studies confirmed that the (dT-dG)n . (dC-dA)n tract in supercoiled pRW777 was in a left-handed helix.
Source: Journal of Biological Chemistry
Authors: C K Singleton, M W Kilpatrick, R D Wells
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $3,430
OpenAlex ID: W1517351575