pparδ may function as an integrator of transcription repression and nuclear receptor signaling. it activates transcription of a variety of target genes by binding to specific dna elements. well described include pdk4, angptl4, plin2, and cd36. the expression of this gene is found to be elevated in colorectal cancer cells. the elevated expression can be repressed by adenomatosis polyposis coli (apc), a tumor suppressor protein involved in the apc/beta-catenin signaling pathway. knockout studies in mice suggested the role of this protein in myelination of the corpus callosum, epidermal cell proliferation, and glucose and lipid metabolism.