Oct 6, 1998

Transporters of nucleotide sugars, ATP, and nucleotide sulfate in the endoplasmic reticulum and Golgi apparatus

Annual Review of Biochemistry
C B HirschbergC Abeijon


The lumens of the endoplasmic reticulum and Golgi apparatus are the subcellular sites where glycosylation, sulfation, and phosphorylation of secretory and membrane-bound proteins, proteoglycans, and lipids occur. Nucleotide sugars, nucleotide sulfate, and ATP are substrates for these reactions. ATP is also used as an energy source in the lumen of the endoplasmic reticulum during protein folding and degradation. The above nucleotide derivatives and ATP must first be translocated across the membrane of the endoplasmic reticulum and/or Golgi apparatus before they can serve as substrates in the above lumenal reactions. Translocation of the above solutes is mediated for highly specific transporters, which are antiporters with the corresponding nucleoside monophosphates as shown by biochemical and genetic approaches. Mutants in mammals, yeast, and protozoa showed that a defect in a specific translocator activity results in selective impairments of the above posttranslational modifications, including loss of virulence of pathogenic protozoa. Several of these transporters have been purified and cloned. Experiments with yeast and mammalian cells demonstrate that these transporters play a regulatory role in the above reactions. Future st...Continue Reading

Mentioned in this Paper

Golgi Membrane
UDP-galactose transporter
Biochemical Pathway
Nucleoside diphosphatase
ATP Transport

Related Feeds

CFTR Mutant Structural Therapy

Over 1700 different mutations in the CFTR genes have been shown to cause cystic fibrosis. Here is the latest research on structural therapy for CFTR mutants.