DNA bending by adenine-thymine tracts

Publisher Website
Google Scholar
Abstract
Fifteen years have elapsed since the observations of Marini et al. (1) which associated DNA bending or curvature with the anomalously slow electrophoretic mobility and fast overall rotational relaxation observed for DNA restriction fragments from the kinetoplast body of Leishmania tarentolae. Confirmation of increased curvature soon followed, using techniques such as electric birefringence decay (2) and electron microscopy (3). The sequences responsible for bending were identified as tracts of oligo (dA):oligo (dT), each about half a helical turn long, repeated in phase with the DNA helical screw (4). The experiment on which this conclusion was based relied on the slow electrophoretic mobility of a molecule containing a bend at its centre, compared with a circularly permuted sequence variant in which the bend is at the end. A simple rule of thumb in interpreting such experiments is that the shorter the end-to-end distance in molecules of equal contour length, the slower the electrophoretic mobility (5). Gel electrophoretic methods for characterizing DNA bending have been reviewed by Crothers and Drak (6).

This publication has 0 references indexed in Scilit: