Variants of the primate vesicular monoamine transporter-2

The vesicular monoamine transporter-2 (VMAT2) sequesters monoamine neurotransmitters into vesicles and prevents neurotoxicity. Human or monkey striatum generated three VMAT2 immunoreactive proteins of ∼75 kDa, ∼52-55 kDa, and ∼45 kDa. The ∼55-kDa band is considered the unglycosylated native protein. Deglycosylation of the VMAT2 from striatum or human VMAT2 expressed in HEK293 cells yielded a ∼45-kDa, but not a 55-kDa immunoreactive band. We investigated this apparent mismatch between observed molecular size and predicted size.