FABP are thought to play a role in the intracellular transport of long-chain fatty acids and their acyl-CoA esters. MDGI reversibly inhibits proliferation of mammary carcinoma cells. Mammary epithelial cells of developing lobuloalveolar structures and heart. Forms a beta-barrel structure that accommodates the hydrophobic ligand in its interior. Belongs to the calycin superfamily. Fatty-acid binding protein (FABP) family.