RT Journal Article
SR Electronic
T1 Growth Factors do not regulate Golgi Complex-to-ER relocation of GalNAc-Ts in HeLa cells
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 071225
DO 10.1101/071225
A1 Gaetan G. Herbomel
A1 Raul E. Rojas
A1 Duy T. Tran
A1 Monica Ajinkya
A1 Lauren Beck
A1 Lawrence A. Tabak
YR 2016
UL http://biorxiv.org/content/early/2016/08/23/071225.abstract
AB Mucin-type O-glycosylation is initiated by the UDP-GalNAc polypeptide:N-acetylgalactosaminyltransferase (GalNAc-T) family of enzymes. Their activity results in the GalNAc α1-O-Thr/Ser structure, termed the Tn antigen, which is further decorated with additional sugars. In neoplastic cells, the Tn antigen is often overexpressed. Because O-glycosylation is controlled by the activity of GalNAc-Ts, their regulation is of great interest. Previous reports suggest that growth factors, EGF or PDGF, induce Golgi complex-to-endoplasmic reticulum (ER) relocation of both GalNAc-Ts and Tn antigen in HeLa cells, offering a mechanism for Tn antigen overexpression termed “GALA”. However, we were unable to reproduce these findings. Upon treatment of HeLa cells with either EGF or PDGF we observed no change in the co-localization of endogenous GalNAc-T1, GalNAc-T2 or Tn antigen with the Golgi complex marker TGN46. There was also no enhancement of localization with the ER marker calnexin. We conclude that growth factors do not cause redistribution of GalNAc-Ts from the Golgi complex to the ER in HeLa cells.GalNAc-TUDP-GalNAc polypeptide:N acetylgalactosaminyltransferaseGalNAcN-acetylgalactosamineEREndoplasmic reticulumEGFEpidermal growth factorPDGFPlatelet-derived growth factorMAPKMitogen-activated protein kinaseNANumerical aperatureAUAiry unitMCCManders’ correlation coefficient