Adiponectin Receptor 1 (ADIPOR1)

Human ADIPOR1 also has 375 amino acids and shares 96.8% identity with the mouse protein. ADIPOR1 and ADIPOR2 are highly related structurally, and mouse Adipor1 and Adipor2 share 66.7% identity. ADIPOR1 and ADIPOR2 are 7-transmembrane domain proteins, but they are structurally, topologically, and functionally distinct from G protein-coupled receptors (GPCRs). Epitope tag labeling showed that the N terminus is internal and the C terminus is external in the ADIPORs, a topology opposite that of GPCRs. ADIPOR1 and ADIPOR2 are conserved from yeast to human, especially in the membrane-spanning regions. The authors noted that the yeast homolog has a principal role in metabolic pathways that regulate lipid metabolism, such as fatty acid oxidation.