通过在聚丙烯酰胺溶液中进行电泳来分离长度为4.4 kb的环状、带切口环状和线性DNA。

Resolution of circular, nicked circular and linear DNA, 4.4 kb in length, by electrophoresis in polyacrylamide solutions.

作者信息

Garner M M, Chrambach A

机构信息

Section on Macromolecular Analysis, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892.

出版信息

Electrophoresis. 1992 Mar;13(3):176-8. doi: 10.1002/elps.1150130136.

DOI:10.1002/elps.1150130136

PMID:1592050

Abstract

Circular DNA of more than 1,400 bp in size is known not to migrate into polyacrylamide gels. The migration of supercoiled plasmid pBR322 DNA (4,363 by) into uncrosslinked polyacrylamide (Mw 5 x 10(6)) solutions and its separation, on the basis of conformation, from its nicked form is demonstrated in this study. Migration of the supercoiled, nicked circular and linear forms of the plasmid DNA is retarded in proportion to the concentration of uncrosslinked polyacrylamide, the degree of retardation being highest for the nicked circular form. Decreasing the level of supercoiling of the covalently closed circular form by decreasing the concentration of the intercalating dye (ethidium homodimer) shows that the degree of retardation decreases in proportion to the superhelix density.

摘要

已知大小超过1400 bp的环状DNA不会迁移到聚丙烯酰胺凝胶中。本研究证明了超螺旋质粒pBR322 DNA（4363 bp）迁移到未交联的聚丙烯酰胺（Mw 5×10⁶）溶液中，并根据构象与切口形式分离。质粒DNA的超螺旋、切口环状和线性形式的迁移与未交联聚丙烯酰胺的浓度成比例地受到阻碍，其中切口环状形式的阻碍程度最高。通过降低嵌入染料（乙锭同二聚体）的浓度来降低共价闭合环状形式的超螺旋水平，结果表明阻碍程度与超螺旋密度成比例降低。