In early differentiation stage 3T3 L1 cells , __SP__ __NODE__ protein decreases transcription of reporter gene with a DNA endogenous promoter ( 2232 17 ) containing a multiple copies ( 2 times ) CCAAT/Enhancer Binding Protein binding site from the __SP__ __NODE__ gene that involves __NODE__ and __NODE__ protein and 3 isobutyl 1 methylxanthine .