Fig 4. Electrophoretic mobility shift assay (EMSA) for testing the DNA binding ability of Stl constructs.

(A) Result of EMSA with the wild type Stl protein. Note that the DNA band is shifted upwards at 1 μM Stl concentration. (B) EMSA gel result of Stl-AA mutant protein. Note that even at relatively high (ie. 3 μM) concentration of the Stl-AA mutant construct, most DNA still appears at the lower position on the gel, indicating lack of binding to the mutant protein.