| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1 Renal Section, Boston University Medical Center, and Departments of 2 Medicine, 3 Physiology, and 4 Pathology, Boston University School of Medicine, Boston, Massachusetts 02118
The trafficking of H+-ATPase vesicles to the apical membrane of inner medullary collecting duct (IMCD) cells utilizes a mechanism similar to that described in neurosecretory cells involving soluble N-ethylmaleimide-sensitive factor attachment protein target receptor (SNARE) proteins. Regulated exocytosis of these vesicles is associated with the formation of SNARE complexes. Clostridial neurotoxins that specifically cleave the target (t-) SNARE, syntaxin-1, or the vesicle SNARE, vesicle-associated membrane protein-2, reduce SNARE complex formation, H+-ATPase translocation to the apical membrane, and inhibit H+ secretion. The purpose of these experiments was to characterize the physiological role of a second t-SNARE, soluble N-ethylmaleimide-sensitive factor attachment protein (SNAP)-23, a homologue of the neuronal SNAP-25, in regulated exocytosis of H+-ATPase vesicles. Our experiments document that 25-50 nM botulinum toxin (Bot) A or E cleaves rat SNAP-23 and thereby reduces immunodetectable and 35S-labeled SNAP-23 by >60% within 60 min. Addition of 25 nM BotE to IMCD homogenates reduces the amount of the 20 S-like SNARE complex that can be immunoprecipitated from the homogenate. Treatment of intact IMCD monolayers with BotE reduces the amount of H+-ATPase translocated to the apical membrane by 52 ± 2% of control and reduces the rate of H+ secretion by 77 ± 3% after acute cell acidification. We conclude that SNAP-23 is a substrate for botulinum toxin proteolysis and has a critical role in the regulation of H+-ATPase exocytosis and H+ secretion in these renal epithelial cells.
soluble N-ethylmaleimide-sensitive factor attachment protein target receptor; soluble N-ethylmaleimide-sensitive factor attachment protein; botulinum toxins; proton pumps; hydrogen ion secretion
This article has been cited by other articles:
|
|
 |
|
  A. Yasuhara, J. Wada, S. M. Malakauskas, Y. Zhang, J. Eguchi, A. Nakatsuka, K. Murakami, M. Kanzaki, S. Teshigawara, K. Yamagata, et al. Collectrin Is Involved in the Development of Salt-Sensitive Hypertension by Facilitating the Membrane Trafficking of Apical Membrane Proteins via Interaction With Soluble N-Ethylmaleiamide-Sensitive Factor Attachment Protein Receptor Complex Circulation, November 18, 2008; 118(21): 2146 - 2155. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. Cocucci, G. Racchetti, M. Rupnik, and J. Meldolesi The regulated exocytosis of enlargeosomes is mediated by a SNARE machinery that includes VAMP4 J. Cell Sci., September 15, 2008; 121(18): 2983 - 2991. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Breton and D. Brown New insights into the regulation of V-ATPase-dependent proton secretion Am J Physiol Renal Physiol, January 1, 2007; 292(1): F1 - F10. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 B. Etschmann, K. S. Heipertz, A. von der Schulenburg, and M. Schweigel A vH+-ATPase is present in cultured sheep ruminal epithelial cells Am J Physiol Gastrointest Liver Physiol, December 1, 2006; 291(6): G1171 - G1179. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. A. Ortiz cAMP increases surface expression of NKCC2 in rat thick ascending limbs: role of VAMP Am J Physiol Renal Physiol, March 1, 2006; 290(3): F608 - F616. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 N. Pastor-Soler, C. Pietrement, and S. Breton Role of Acid/Base Transporters in the Male Reproductive Tract and Potential Consequences of Their Malfunction Physiology, December 1, 2005; 20(6): 417 - 428. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. Li, Q. Yang, E. A. Alexander, and J. H. Schwartz Syntaxin 1A has a specific binding site in the H3 domain that is critical for targeting of H+-ATPase to apical membrane of renal epithelial cells Am J Physiol Cell Physiol, September 1, 2005; 289(3): C665 - C672. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. A. Nicoletta, J. J. Ross, G. Li, Q. Cheng, J. Schwartz, E. A. Alexander, and J. H. Schwartz Munc-18-2 regulates exocytosis of H+-ATPase in rat inner medullary collecting duct cells Am J Physiol Cell Physiol, November 1, 2004; 287(5): C1366 - C1374. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. A. Wagner, K. E. Finberg, S. Breton, V. Marshansky, D. Brown, and J. P. Geibel Renal Vacuolar H+-ATPase Physiol Rev, October 1, 2004; 84(4): 1263 - 1314. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. L. TUMA and A. L. HUBBARD Transcytosis: Crossing Cellular Barriers Physiol Rev, July 1, 2003; 83(3): 871 - 932. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Gouraud, A. Laera, G. Calamita, M. Carmosino, G. Procino, O. Rossetto, R. Mannucci, W. Rosenthal, M. Svelto, and G. Valenti Functional involvement of VAMP/synaptobrevin-2 in cAMP-stimulated aquaporin 2 translocation in renal collecting duct cells J. Cell Sci., September 15, 2002; 115(18): 3667 - 3674. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
