Journal of Histochemistry and Cytochemistry Priciples for Free Access to Science
  Search:   
    >> Advanced Search

Guidelines | Subscriptions | About | exPRESS - Current - Archive | Business Information | Contact
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Holappa, K.
Right arrow Articles by Kellokumpu, S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Holappa, K.
Right arrow Articles by Kellokumpu, S.
Social Bookmarking
 Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati  
What's this?
Journal of Histochemistry and Cytochemistry, Vol. 49, 259-270, February 2001, Copyright © 2001, The Histochemical Society, Inc.


ARTICLE

Identification of the Full-length AE2 (AE2a) Isoform as the Golgi-associated Anion Exchanger in Fibroblasts

Katja Holappaa,b, Marko Suokasa,b, Paula Soininena, and Sakari Kellokumpua,b
a University of Oulu, Department of Anatomy and Cell Biology, Oulu, Finland
b Department of Biochemistry, Oulu, Finland

Correspondence to: Katja Holappa, Dept. of Biochemistry, University of Oulu, PO Box 3000, FIN-90014 Oulu, Finland. E-mail: kholappa@cc.oulu.fi

Na+-independent Cl-/HCO3- exchangers (AE1, AE2, AE3) are generally known as ubiquitous, multispanning plasma membrane proteins that regulate intracellular pH and transepithelial acid–base balance in animal tissues. However, previous immunological evidence has suggested that anion exchanger (AE) proteins may also be present in intracellular membranes, including membranes of the Golgi complex and mitochondria. Here we provide several lines of evidence to show that an AE protein is indeed a resident of the Golgi membranes and that this protein corresponds to the full-length AE2a isoform in fibroblasts. First, both the N- and C-terminal antibodies to AE2 (but not to AE1) detected an AE protein in the Golgi membranes. Golgi localization of this AE2 antigen was evident also in cycloheximide-treated cells, indicating that it is a true Golgi-resident protein. Second, our Northern blotting and RT-PCR analyses demonstrated the presence of only the full-length AE2a mRNA in cells that show prominent Golgi staining with antibodies to AE2. Third, antisense oligonucleotides directed against the translational initiation site of the AE2a mRNA markedly inhibited the expression of the endogenous AE2 protein in the Golgi. Finally, transient expression of the GFP-tagged full-length AE2a protein resulted in predominant accumulation of the fusion protein in the Golgi membranes in COS-7 and CHO-K1 cells. Golgi localization of the AE2a probably involves its oligomerization and/or association with the recently identified Golgi membrane skeleton, because a substantial portion of both the endogenous AE2a and the GFP-tagged fusion protein resisted detergent extraction in cold. (J Histochem Cytochem 49:259–269, 2001)

Key Words: Golgi, anion exchanger, fibroblast, expression, protein sorting, cytoskeleton, immunocytochemistry


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


This article has been cited by other articles:


Home page
J. Exp. Biol.Home page
K. H. Ahmed and B. Pelster
Ionic determinants of pH of acidic compartments under hypertonic conditions in trout hepatocytes
J. Exp. Biol., October 15, 2008; 211(20): 3306 - 3314.
[Abstract] [Full Text] [PDF]


Home page
PhysiologyHome page
P. Paroutis, N. Touret, and S. Grinstein
The pH of the Secretory Pathway: Measurement, Determinants, and Regulation
Physiology, August 1, 2004; 19(4): 207 - 215.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Cell Physiol.Home page
M. N. Chernova, A. K. Stewart, L. Jiang, D. J. Friedman, Y. Z. Kunes, and S. L. Alper
Structure-function relationships of AE2 regulation by Ca2+i-sensitive stimulators NH+4 and hypertonicity
Am J Physiol Cell Physiol, May 1, 2003; 284(5): C1235 - C1246.
[Abstract] [Full Text] [PDF]


Home page
Am. J. Physiol. Lung Cell. Mol. Physiol.Home page
J. L. Turi, I. Jaspers, L. A. Dailey, M. C. Madden, L. E. Brighton, J. D. Carter, E. Nozik-Grayck, C. A. Piantadosi, and A. J. Ghio
Oxidative stress activates anion exchange protein 2 and AP-1 in airway epithelial cells
Am J Physiol Lung Cell Mol Physiol, October 1, 2002; 283(4): L791 - L798.
[Abstract] [Full Text] [PDF]




Guidelines | Subscriptions | About | exPRESS - Current - Archive | Business Information | Contact
The Journal of Histochemistry & Cytochemistry is owned, published, and licensed by The Histochemical Society © 2001