Identification of multiple protein binding domains in the promoter-regulatory region of the phosphoenolpyruvate carboxykinase (GTP) gene.

摘要: Transcription of the gene for cytosolic form phosphoenolpyruvate carboxykinase (GTP) (EC 4.1.1.32) (PEPCK) from rat is acutely regulated by a number hormones, including glucagon (acting via cAMP), glucocorticoids, and insulin. In this study we demonstrate DNase I footprinting that region PEPCK promoter, extending −460 to +73, contained eight protein binding domains. Two nuclear proteins protected adjacent sites −121 −99 −96 −77, which have been previously shown be involved in maintaining level basal transcription conferring cAMP responsiveness, respectively. Oligonucleotide competition studies suggested protein(s) cAMP-responsive element (CRE) occupies second site at −147 −130, has high degree sequence homology CRE, also binds two other elements show partial homologies. The bound these four copurified through oligonucleotide affinity chromatography, suggesting promoter CRE-binding protein(s). Potential tissue-specific were identified with extracts prepared liver, kidney, brain, spleen. multiple protein-binding promoter-regulatory reflect complex transcriptional regulation characteristic gene.