In a cell free system , binding of a DNA fragment containing a __NODE__ response element from __NODE__ gene(s) and heterodimer consisting of __SP__ __NODE__ and of mutant __SP__ __NODE__ ( deletion 276 ) is the same as binding of a DNA fragment containing a __NODE__ response element from __NODE__ gene(s) and heterodimer consisting of __SP__ __NODE__ and of __SP__ __NODE__ .