In a cell free system , binding of promoter fragment ( 97 78 ) from __SP__ __NODE__ gene consisting of PPRE and __SP__ __NODE__ protein is greater than binding of mutant promoter fragment ( 97 78 ) ( G 83C A 82C T 81C T 80A with its PPRE mutated ) from __SP__ __NODE__ gene consisting of PPRE and __SP__ __NODE__ protein .