Synthesis of prepro-Glucose-dependent Insulinotropic Polypeptide (preproGIP) in Intestinal K Cells Authored: May, B, 2009-05-18 21:31:59 Edited: May, B, 2009-09-09 Pubmed16219666 Pubmed18593849 Pubmed8428636 Reactome Database ID Release 43400500 Reactome, http://www.reactome.org ReactomeREACT_23838 Reviewed: Bloom, SR, 2010-06-24 The transcription factors PDX-1 and PAX6 binds the promoter of the human GIP gene between 145 and 184 nucleotides upstream of the start of transcription and enhance transcription of GIP. In mouse Pdx-1 also increases the number of GIP-producing K cells. Consensus binding sites for other transcription factors such as AP-1, AP-2, and Sp1 have been identified in the promoter of the GIP gene but their role is unknown. The human GIP promoter is responsive to cAMP by an unknown mechanism.