MCT1 is a proton-linked transport carrier that catalyzes the movement of short chain monocarboxylates (branched-chain oxo acids derived from leucine, valine, and isoleucine) across both plasma and inner mitochondrial membranes. In particular, substances such as lactate, pyruvate, butyrate, and ketone bodies are shuttled; these play big roles in cell metabolism particularly in tissues and organs like the kidney, intestine, liver, and brain.
