VMaT 2 (vesicular monoamine transporter 2)

Monoamine transporter in the membrane of small synaptic vesicles

General Information

Vesicular monoamine transporters VMaTs mediate the translocation of monoamines (serotonin, histamine, dopamine) from the cytoplasm into secretory vesicles by using a proton electrochemical gradient.
VMaTs are integral membrane proteins with 12 putative trans-membrane domains predicted by sequence analysis. Both, the N- and C-terminus of the proteins are located on the cytoplasmic side.
Two VMaT isoforms, VMaT 1 and VMaT 2, have been described. It has been proposed that VMaT 1 transports monoamines into large dense core vesicles (LDCVs), whereas VMaT 2 is needed for the loading of small synaptic vesicles (SSVs).
In rat VMaT 1 is expressed in the adrenal gland, while VMaT 2 is expressed in brain.