Table 1.

Tg endocytic receptors and their role in Tg endocytosis and intracellular trafficking

Characterized ReceptorsTg Motifs RecognizedRoleReferences
Asialoglycoprotein receptorExposed galactose or
N-acetylgalactosamine residues
Recycling of immature Tg molecules? 18, 19, 69, 75, 76, 80, 82
Megalin (gp330)Multiple amino acid determinantsEndocytosis and transcytosis 6062,108
Postulated or PoorlyCharacterized ReceptorsTg Motifs RecognizedPostulated RoleReferences
N-acetylglucosamine receptorExposed N-acetylglucosamine residuesRecycling of immature Tg 5, 6, 19, 65, 67, 68, 72, 96
Protein disulfide isomeraseExposedN-acetylglucosamine residuesRecycling of immature Tg 65
Mannose-6-phosphate receptorMannose-6-phosphate groupsTg targeting to lysosomes 37, 53, 86
Low-affinity receptors?? 31, 32, 53
Heparan sulfate proteogycansPositively charged protein determinantsFacilitate binding to megalin in rodents 58, 60
  • Tg, thyroglobulin.