Restriction digests of the clone give the following sizes (kb): SalI--3.1; XbaI--3.1; EcoRI/HindIII--2.9, 0.28. Target DNA binding sites can be cloned into the vector and an array of fragments can be generated (by restriction digestion with different enzymes) that are equal in length, but differ in the position of the DNA binding site along the fragment. The reduced mobility of different protein-fragment complexes can then by analyzed by gel electrophoresis to determine the degree of bending induced by protein binding. Cloning vector with lacZ color detection designed for studying the amount of bending induced at a DNA binding site due to DNA-protein interactions. |