Cell-contact mediated modulation of the sialylation of contactinhibin.
Contactinhibin was found to be involved in contact-dependent inhibition of growth. The growth inhibitory activity of contactinhibin is mediated by N-linked oligosaccharides with desialylated beta-glycosidically linked, terminal galactose residues. Here we show that in sparse human fibroblasts contactinhibin was expressed in a biologically inactive, highly sialylated form both on the plasma membrane and intracellularly, while in confluent cells plasma membrane localized contactinhibin was present in a biologically active, low sialylated form. Plasma membranes were shown to contain a glycoprotein sialidase which is suggested to be engaged in the activation of contactinhibin in a cell contact-dependent manner.
Wieser
R J
RJ
Institute of Toxicology, Mainz, Germany.
Baumann
C E
CE
Oesch
F
F
D000906:Antibodies / Q000494:pharmacology; D002450:Cell Communication / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D002462:Cell Membrane / Q000502:physiology; D015180:Electrophoresis, Gel, Two-Dimensional; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D015603:Keratinocytes; D037102:Lectins; D008168:Lung; D008562:Membrane Glycoproteins / Q000276:immunology / Q000302:isolation & purification / Q000502:physiology*; D009439:Neuraminidase / Q000494:pharmacology*; D009844:Oligosaccharides / Q000737:chemistry
D000906:Antibodies; D037102:Lectins; D008562:Membrane Glycoproteins; D009844:Oligosaccharides; D009439:Neuraminidase