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

First published online 2 September 2008
doi: 10.1242/jcs.034496

This Article Figures Only Full Text Full Text (PDF) Supplementary Material All Versions of this Article: jcs.034496v1 121/19/3133    most recent Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend 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 Malli, R. Articles by Graier, W. F. Search for Related Content PubMed PubMed Citation Articles by Malli, R. Articles by Graier, W. F. Social Bookmarking                         What's this?

Cytosolic Ca²⁺ prevents the subplasmalemmal clustering of STIM1: an intrinsic mechanism to avoid Ca²⁺ overload

¹ Institute of Molecular Biology and Biochemistry, Center of Molecular Medicine, Medical University of Graz, Graz, Austria
² Institute of Biophysics, University of Linz, Linz, Austria

^* Author for correspondence (e-mail: wolfgang.graier{at}meduni-graz.at)

Accepted 3 July 2008

Summary

The stromal interacting molecule (STIM1) is pivotal for store-operated Ca²⁺ entry (SOC). STIM1 proteins sense the Ca²⁺ concentration within the lumen of the endoplasmic reticulum (ER) via an EF-hand domain. Dissociation of Ca²⁺ from this domain allows fast oligomerization of STIM1 and the formation of spatially discrete clusters close to the plasma membrane. By lifetime-imaging of STIM1 interaction, the rearrangement of STIM1, ER Ca²⁺ concentration ([Ca²⁺]_ER) and cytosolic Ca²⁺ signals ([Ca²⁺]_cyto) we show that [Ca²⁺]_cyto affects the subcellular distribution of STIM1 oligomers and prevents subplasmalemmal STIM clustering, even if the ER is depleted. These data indicate that [Ca²⁺]_cyto, independently of the ER Ca²⁺ filling state, crucially tunes the formation and disassembly of subplasmalemmal STIM1 clusters, and, thus, protects cells against Ca²⁺ overload resulting from excessive SOC activity.

Key words: ER Ca²⁺ dynamics, FRET, STIM1 oligomerization, Store-operated Ca²⁺ entry

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

				S. Fernandez-Rodriguez, D. H. Edwards, B. Newton, and T. M. Griffith Attenuated store-operated Ca2+ entry underpins the dual inhibition of nitric oxide and EDHF-type relaxations by iodinated contrast media Cardiovasc Res, August 7, 2009; (2009) cvp239v2. [Abstract] [Full Text] [PDF]

				M. Muik, M. Fahrner, I. Derler, R. Schindl, J. Bergsmann, I. Frischauf, K. Groschner, and C. Romanin A Cytosolic Homomerization and a Modulatory Domain within STIM1 C Terminus Determine Coupling to ORAI1 Channels J. Biol. Chem., March 27, 2009; 284(13): 8421 - 8426. [Abstract] [Full Text] [PDF]