Kinesin belongs to the group of microtubule-associated motor proteins known to convert chemical energy released from nucleoside triphosphates (preferentially from ATP) into mechanical energy. Conventional kinesin, member of the kinesin superfamily comprising more than 100 proteins, is involved in the anterograde vesicle transport in neuronal cells. Kinesin purified from mammalian brain homogenates is a heterotetramer consisting of two heavy (120 to 130 kDa) and two light chains (60 to 70 kDa), resulting in a molecular mass about 400 kDa. Each heavy chain contains an N-terminal globular motordomain with both a microtubule-binding site and an ATPase active center, stalk region responsible for heavy chain dimerization and finally C-terminal globular tail domain, which is implicated in cargo binding. Light chains may have a regulatory function.