| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Department of Physiology, University of Extremadura, Cáceres, Spain2 Department of Physiology, University of Cambridge, Cambridge CB2 3EG, UK
Store-mediated Ca2+ entry (SMCE) is a major mechanism for Ca2+ influx in non-excitable cells. Recently, a conformational coupling mechanism allowing coupling between transient receptor potential channels (TRPCs) and IP3 receptors has been proposed to activate SMCE. Here we have investigated the role of two soluble N-ethylmaleimide-sensitive-factor attachment protein receptors (SNAREs), which are involved in membrane trafficking and docking, in SMCE in human platelets. We found that the synaptosome-associated protein (SNAP-25) and the vesicle-associated membrane proteins (VAMP) coimmunoprecipitate with hTRPC1 in platelets. Treatment with botulinum toxin (BoNT) E or with tetanus toxin (TeTx), induced cleavage and inactivation of SNAP-25 and VAMPs, respectively. BoNTs significantly reduced thapsigargin- (TG) and agonist-evoked SMCE. Treatment with BoNTs once SMCE had been activated decreased Ca2+ entry, indicating that SNAP-25 is required for the activation and maintenance of SMCE. In contrast, treatment with TeTx had no effect on either the activation or the maintenance of SMCE in platelets. Finally, treatment with BoNT E impaired the coupling between naturally expressed hTRPC1 and IP3 receptor type II in platelets. From these findings we suggest SNAP-25 has a role in SMCE in human platelets.
(Received 19 March 2004;
accepted after revision 28 April 2004;
first published online 30 April 2004)
Corresponding author J. A. Rosado: Department of Physiology, Faculty of Veterinary Sciences, University of Extremadura, Av. Universidad s/n, Cáceres 10071, Spain. Email: jarosado{at}unex.es
This article has been cited by other articles:
|
|
 |
|
  G. E. Woodard, G. M. Salido, and J. A. Rosado Enhanced exocytotic-like insertion of Orai1 into the plasma membrane upon intracellular Ca2+ store depletion Am J Physiol Cell Physiol, June 1, 2008; 294(6): C1323 - C1331. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 F. Suzuki, S. Morishima, T. Tanaka, and I. Muramatsu Snapin, a New Regulator of Receptor Signaling, Augments {alpha}1A-Adrenoceptor-operated Calcium Influx through TRPC6 J. Biol. Chem., October 5, 2007; 282(40): 29563 - 29573. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Goto, N. Tamura, H. Ishida, and Z. M. Ruggeri Dependence of Platelet Thrombus Stability on Sustained Glycoprotein IIb/IIIa Activation Through Adenosine 5'-Diphosphate Receptor Stimulation and Cyclic Calcium Signaling J. Am. Coll. Cardiol., January 3, 2006; 47(1): 155 - 162. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Y. Dobrydneva, C. J. Abelt, B. Dovel, C. M. Thadigiri, R. L. Williams, and P. F. Blackmore 2-Aminoethoxydiphenyl Borate as a Prototype Drug for a Group of Structurally Related Calcium Channel Blockers in Human Platelets Mol. Pharmacol., January 1, 2006; 69(1): 247 - 256. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. A. Rosado, P. C. Redondo, G. M. Salido, S. O. Sage, and J. A. Pariente Cleavage of SNAP-25 and VAMP-2 impairs store-operated Ca2+ entry in mouse pancreatic acinar cells Am J Physiol Cell Physiol, January 1, 2005; 288(1): C214 - C221. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
