In a system of purified components , the affinity of binding of a DNA fragment ( TCGACTCTGACCTCTCGTTGACCTGCT ) containing a __NODE__ __NODE__ response element and __NODE__ protein and __NODE__ protein is greater than the affinity of binding of a DNA fragment ( TCGACTCTGACCTCTCGTTGACCTGCT ) containing a __NODE__ __NODE__ response element and dimeric __NODE__ protein .