HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

J. Biol. Chem., Vol. 275, Issue 41, 31946-31953, October 13, 2000

This Article Full Text Full Text (PDF) All Versions of this Article: 275/41/31946    most recent M003559200v1 Submit a Letter to Editor Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map 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 Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Zhang, X. Articles by Arvan, P. Search for Related Content PubMed PubMed Citation Articles by Zhang, X. Articles by Arvan, P. Social Bookmarking                      What's this?

Cell Type-dependent Differences in Thyroid Peroxidase Cell Surface Expression^*

Xiaoqing Zhang^§ and Peter Arvan^§¶

From the  Division of Endocrinology and ^§ Department of Developmental and Molecular Biology, Albert Einstein College of Medicine, Bronx, New York 10461

Recently, it has been suggested that only ~2% of human thyroid peroxidase (hTPO₉₃₃) reaches the surface of stably transfected (Chinese hamster ovary) cells, most being degraded intracellularly, and this might be representative of thyroid peroxidase (TPO) behavior in thyrocytes (Fayadat, L., Siffroi-Fernandez, S., Lanet, J., and Franc, J.-L. (2000) J. Biol. Chem. 275, 15948-15954). In agreement, in stably transfected Madin-Darby canine kidney clones, nonpermeabilized cells exhibit wild-type hTPO₉₃₃ immunofluorescence (apically) on <10% of that found in permeabilized cells, where an endoplasmic reticulum pattern is observed. Further, a C-terminally truncated, membrane-anchorless hTPO₈₄₈ is also retained in the endoplasmic reticulum of stably transfected Madin-Darby canine kidney cells. However, by contrast, in Chinese hamster ovary cells after transient transfection, hTPO₉₃₃ immunofluorescence is detected equally well in nonpermeabilized and permeabilized cells, indicating that a large portion of hTPO₉₃₃ is present at the cell surface; furthermore, hTPO₈₄₈ is efficiently secreted. Further, using an antiserum not cross-reacting with rat TPO, we find by immunofluorescence that in stable clones of PC Cl3 (rat) thyrocytes, considerably more (~50%) of the cells exhibit hTPO₉₃₃ at the cell surface. However, cell surface biotinylation and endoglycosidase H digestion assays appear to under-represent the extent of hTPO₉₃₃ transport, presumably because protein folding limits both Golgi carbohydrate modification and accessibility of lysines in the extracellular domain. We conclude that cell type-specific factors may facilitate stable expression of TPO at the cell surface of thyrocytes.

CiteULike

Complore

Connotea

Del.icio.us

Digg

Reddit

Technorati

This article has been cited by other articles:

				H. Grasberger, X. De Deken, F. Miot, J. Pohlenz, and S. Refetoff Missense Mutations of Dual Oxidase 2 (DUOX2) Implicated in Congenital Hypothyroidism Have Impaired Trafficking in Cells Reconstituted with DUOX2 Maturation Factor Mol. Endocrinol., June 1, 2007; 21(6): 1408 - 1421. [Abstract] [Full Text] [PDF]

				R. Kuliawat, J. Ramos-Castaneda, Y. Liu, and P. Arvan Intracellular Trafficking of Thyroid Peroxidase to the Cell Surface J. Biol. Chem., July 29, 2005; 280(30): 27713 - 27718. [Abstract] [Full Text] [PDF]

				F. Martin-Belmonte, M. A. Alonso, X. Zhang, and P. Arvan Thyroglobulin Is Selected as Luminal Protein Cargo for Apical Transport via Detergent-resistant Membranes in Epithelial Cells J. Biol. Chem., December 22, 2000; 275(52): 41074 - 41081. [Abstract] [Full Text] [PDF]