Solute carrier organic anion transporter 5 family of the Major Facilitator Superfamily of transporters
The Solute carrier organic anion transporter 5 (SLCO5) or Organic anion transporting polypeptide 5 (OATP5) family contains only one subfamily, OATP5A, which contains only one mammalian member OATP5A1 (encoded by SLCO5A1). Deletion of the SLCO5A1 gene has been implicated in the pathogenesis of Mesomelia-synostoses syndrome (MSS), a rare autosomal-dominant disorder characterized by mesomelic limb shortening, acral synostoses, and multiple congenital malformations. OATP5A1 may be a non-classical OATP which is involved in biological processes that require the reorganization of the cell shape, such as differentiation and migration. It seems to affect intracellular transport of drugs and may participate in chemoresistance of small cell lung cancer (SCLC by sequestration), rather than mediating cellular uptake. The SLCO5/OATP5 family belongs to the Solute carrier organic anion transporter [SLCO, also called organic anion transporting polypeptides (OATPs) or Solute carrier family 21] family of the Major Facilitator Superfamily (MFS) of transporters. MFS proteins are thought to function through a single substrate binding site, alternating-access mechanism involving a rocker-switch type of movement.
Feature 1:putative chemical substrate binding pocket [chemical binding site]
Evidence:
Comment:based on the structures of MFS transporters with bound substrates, substrate analogs, and/or inhibitors
Comment:since MFS proteins facilitate the transport of many different substrates including ions, sugar phosphates, drugs, neurotransmitters, nucleosides, amino acids, and peptides, the residues involved in substrate binding may not be strictly conserved among superfamily members
Comment:the substrate binding site or translocation pore has access to both sides of the membrane in an alternating fashion through a conformational change of the MFS transporter