Responsiveness of glycosyltransferases to thyrotropin in a serum-free culture of porcine thyroid cells.
Administration of thyrotropin to porcine thyroid follicles, obtained in a serum-free chemically defined medium, provoked marked increases in the activities of several glycosyltransferases involved in protein N-glycosylation. The coincidence of these effects with a previously demonstrated enhancement of thyroglobulin production renders a relationship between these events likely. The most important stimulation was for peptide oligosaccharyltransferase (3-fold). Among the enzymes involved in the synthesis of the lipid oligosaccharide donor, Dol-P glycosyl- and mannosyltransferases were increased 1.5-fold, and Dol-P N-acetylglucosaminylphosphotransferase only 1.15-fold. As regards terminal glycosyltransferases, asialofetuin sialyltransferase was increased 2-fold and ovomucoid galactosyltransferase only 1.2-fold. There was a continuous release of the latter two enzymes into the culture medium.
D000818:Animals; D001769:Blood; D002478:Cells, Cultured; D005700:Galactosyltransferases / Q000032:analysis; D005964:Glucosyltransferases / Q000032:analysis; D006602:Hexosyltransferases / Q000032:analysis*; D008364:Mannosyltransferases / Q000032:analysis; D010770:Phosphotransferases / Q000032:analysis*; D012799:Sialyltransferases / Q000032:analysis; D013552:Swine; D013961:Thyroid Gland / Q000201:enzymology*; D013972:Thyrotropin / Q000494:pharmacology*; D017855:Transferases (Other Substituted Phosphate Groups); D000094802:beta-D-Galactoside alpha 2-6-Sialyltransferase
D013972:Thyrotropin; D005700:Galactosyltransferases; D005964:Glucosyltransferases; D006602:Hexosyltransferases; D008364:Mannosyltransferases; D012799:Sialyltransferases; D010770:Phosphotransferases; D017855:Transferases (Other Substituted Phosphate Groups); C030012:UDP-N-acetylglucosamine-lysosomal-enzyme-N-acetylglucosaminephosphotransferase; D000094802:beta-D-Galactoside alpha 2-6-Sialyltransferase