QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

First published online 8 March 2005
doi: 10.1242/jcs.01710

This Article Figures Only Full Text Full Text (PDF) All Versions of this Article: jcs.01710v1 118/7/1363    most recent Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Related articles in JCS Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Atiya-Nasagi, Y. Articles by Sagi-Eisenberg, R. Search for Related Content PubMed PubMed Citation Articles by Atiya-Nasagi, Y. Articles by Sagi-Eisenberg, R.

O-glycosylation is essential for intracellular targeting of synaptotagmins I and II in non-neuronal specialized secretory cells

¹ Department of Cell and Developmental Biology, Sackler School of Medicine, Tel Aviv University, Tel Aviv 69978, Israel
² Fukuda Initiative Research Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan

^* Author for correspondence (e-mail: histol3{at}post.tau.ac.il)

Accepted 6 January 2005

We have examined the trafficking of synaptotagmin (Syt) I and II in the mast cell line rat basophilic leukemia (RBL-2H3). We demonstrate that both Syt I and Syt II travel through the plasma membrane and require endocytosis to reach their final intracellular localization. However, N- or C-terminal tagging of Syt II, but not of Syt I, prevents its internalization, trapping the tagged protein at the plasma membrane. Furthermore, a chimeric protein comprising a tagged luminal domain of Syt II fused with the remaining domains of Syt I also localizes to the plasma membrane, whereas a chimera consisting of tagged luminal domain of Syt I fused with Syt II colocalizes with Syt I on secretory granules. We also show that endocytosis of both Syt I and Syt II is strictly dependent on O-glycosylation processing, whereby O-glycosylation mutants of either protein fail to internalize and remain at the plasma membrane. Our results indicate that the luminal domains of Syt I and Syt II govern their internalization capacity from the plasma membrane and identify O-glycosylation as playing a crucial role in Syt trafficking in non-neuronal secretory cells.

Key words: Sorting, Glycosylation, Synaptotagmin, RBL-2H3

Related articles in JCS:

Sorting out the synaptotagmins

JCS 2005 118: 705. [Full Text]  

This article has been cited by other articles:

				K. Amano, Y. Chiba, Y. Kasahara, Y. Kato, M. K. Kaneko, A. Kuno, H. Ito, K. Kobayashi, J. Hirabayashi, Y. Jigami, et al. Engineering of mucin-type human glycoproteins in yeast cells PNAS, March 4, 2008; 105(9): 3232 - 3237. [Abstract] [Full Text] [PDF]

				K. Kato, C. Jeanneau, M. A. Tarp, A. Benet-Pages, B. Lorenz-Depiereux, E. P. Bennett, U. Mandel, T. M. Strom, and H. Clausen Polypeptide GalNAc-transferase T3 and Familial Tumoral Calcinosis: SECRETION OF FIBROBLAST GROWTH FACTOR 23 REQUIRES O-GLYCOSYLATION J. Biol. Chem., July 7, 2006; 281(27): 18370 - 18377. [Abstract] [Full Text] [PDF]

				A. G. Remacle, A. V. Chekanov, V. S. Golubkov, A. Y. Savinov, D. V. Rozanov, and A. Y. Strongin O-Glycosylation Regulates Autolysis of Cellular Membrane Type-1 Matrix Metalloproteinase (MT1-MMP) J. Biol. Chem., June 23, 2006; 281(25): 16897 - 16905. [Abstract] [Full Text] [PDF]