Developmentally regulated glycosylation of dopamine transporter.
The dopamine transporter (DAT) in rat striatum was examined during postnatal development and aging after photolabeling with [125I]DEEP. The DAT-[125I]DEEP protein complex from adult rats (2 months) appeared as a broad diffuse band in SDS-PAGE gels with average apparent molecular mass of about 80,000 Da as previously found. However, the molecular mass was lower at birth (day 0) and at postnatal ages 4 and 14 days. In aged rats (104 weeks), the molecular mass was slightly higher than that found in young adults (60 days). In binding experiments with [3H]BTCP, there were age-related differences in Kd and Bmax with decreases in both Kd and Bmax found in aged rats. Treatment of photolabeled membranes with neuraminidase caused a reduction in DAT molecular mass, but age-related differences were maintained. Treatment with N-glycanase greatly reduced or eliminated the age-related differences. Several DAT peptide-specific polyclonal antibodies immunoprecipitated DAT-[125I]DEEP protein complex at different developmental ages. Taken together, these results suggest differential glycosylation of rat DAT occurs during postnatal development and aging; the increase is due to increases in the N-linked sugars rather than changes in either sialic acid content or the polypeptide.
Patel
A P
AP
National Institutes of Health, National Institute on Drug Abuse, Addiction Research Center, Baltimore, MD 21224.
Cerruti
C
C
Vaughan
R A
RA
Kuhar
M J
MJ
D000375:Aging / Q000378:metabolism*; D000595:Amino Acid Sequence; D000818:Animals; D001386:Azides / Q000378:metabolism; D002352:Carrier Proteins / Q000737:chemistry / Q000378:metabolism*; D002462:Cell Membrane / Q000378:metabolism / Q000648:ultrastructure; D004298:Dopamine / Q000378:metabolism; D018491:Dopamine Agonists / Q000378:metabolism; D050483:Dopamine Plasma Membrane Transport Proteins; D005260:Female; D006031:Glycosylation; D007700:Kinetics; D008297:Male; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins; D010622:Phencyclidine / Q000031:analogs & derivatives / Q000378:metabolism; D010879:Piperazines / Q000378:metabolism; D011247:Pregnancy; D011499:Protein Processing, Post-Translational; D017433:Protein Structure, Secondary; D051381:Rats; D017207:Rats, Sprague-Dawley; D012794:Sialic Acids / Q000032:analysis
D001386:Azides; D002352:Carrier Proteins; D018491:Dopamine Agonists; D050483:Dopamine Plasma Membrane Transport Proteins; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D010879:Piperazines; D012794:Sialic Acids; C493216:Slc6a3 protein, rat; C056415:1-(1-(2-benzo(b)thienyl)cyclohexyl)piperidine; C060753:1-(2-(diphenylmethoxy)ethyl)-4-(2-(4-azido-3-iodophenyl)ethyl)piperazine; D010622:Phencyclidine; D004298:Dopamine