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

First published online 17 January 2006
doi: 10.1242/jcs.02770

This Article Figures Only Full Text Full Text (PDF) All Versions of this Article: jcs.02770v1 119/3/532    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 Lai, A. Articles by Charles, A. C. Search for Related Content PubMed PubMed Citation Articles by Lai, A. Articles by Charles, A. C.

Oculodentodigital dysplasia connexin43 mutations result in non-functional connexin hemichannels and gap junctions in C6 glioma cells

¹ Department of Neurology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
² The Henry E Singleton Brain Cancer Research Program, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
³ Institute of Genetic Medicine, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
⁴ Departments of Medicine and Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA

^* Author for correspondence (email: albertlai{at}mednet.ucla.edu)

Accepted 31 October 2005

Oculodentodigital dysplasia (ODDD) is a rare developmental disorder characterized by craniofacial and limb abnormalities. Over 35 separate mutations in human connexin43 (Cx43) causing ODDD have been identified. Several mutations are also associated with central nervous system involvement, including white-matter changes detected by magnetic resonance imaging. As Cx43 is abundantly expressed in astrocytes, we hypothesized that the mutant Cx43 proteins that produce neurological dysfunction have abnormal functional characteristics in astrocytes. To understand how ODDD-associated mutations affect Cx43 signaling in cells of glial origin, we conducted studies in rat C6 glioma cells, a communication-deficient glial cell line that expresses low levels of Cx43. We generated stable cell lines expressing enhanced yellow fluorescent protein (eYFP)-tagged human Cx43 constructs encoding wild-type and six eYFP-tagged mutant Cx43 mutants: Y17S, G21R, A40V, F52dup, L90V and I130T. Of these, Y17S, L90V and I130T are associated with neurological abnormalities. We found that all mutants could be detected on the cell surface. Y17S, G21R, A40V, L90V and I130T formed triton-resistant plaques representing gap junctions, although the relative ability to form plaques was decreased in these mutants compared with the wild type. F52dup formed dramatically reduced numbers of plaques. Propidium iodide uptake experiments demonstrated that all mutants were associated with reduced connexin hemichannel function compared with wild type. Scrape-loading experiments performed on the same stable cell lines showed reduced gap junctional dye transfer in all mutants compared with the wild type. These studies demonstrated that ODDD-associated Cx43 mutations result in non-functional connexin hemichannels and gap junction functions in a glial cell line regardless of whether the particular mutant is associated with neurological dysfunction.

Key words: Connexin43, Oculodentodigital dysplasia (ODDD), Hemichannel, Gap junction, Glia

This article has been cited by other articles:

				R. Dobrowolski, P. Sasse, J. W. Schrickel, M. Watkins, J.-S. Kim, M. Rackauskas, C. Troatz, A. Ghanem, K. Tiemann, J. Degen, et al. The conditional connexin43G138R mouse mutant represents a new model of hereditary oculodentodigital dysplasia in humans Hum. Mol. Genet., February 14, 2008; 17(4): 539 - 554. [Abstract] [Full Text] [PDF]

				D. W. Laird Closing the Gap on Autosomal Dominant Connexin-26 and Connexin-43 Mutants Linked to Human Disease J. Biol. Chem., February 8, 2008; 283(6): 2997 - 3001. [Abstract] [Full Text] [PDF]

				N. Kalcheva, J. Qu, N. Sandeep, L. Garcia, J. Zhang, Z. Wang, P. D. Lampe, S. O. Suadicani, D. C. Spray, and G. I. Fishman Gap junction remodeling and cardiac arrhythmogenesis in a murine model of oculodentodigital dysplasia PNAS, December 18, 2007; 104(51): 20512 - 20516. [Abstract] [Full Text] [PDF]

				Y. Zhou, W. Yang, M. M. Lurtz, Y. Ye, Y. Huang, H.-W. Lee, Y. Chen, C. F. Louis, and J. J. Yang Identification of the Calmodulin Binding Domain of Connexin 43 J. Biol. Chem., November 30, 2007; 282(48): 35005 - 35017. [Abstract] [Full Text] [PDF]

				D. Tong, T. Y. Li, K. E. Naus, D. Bai, and G. M. Kidder In vivo analysis of undocked connexin43 gap junction hemichannels in ovarian granulosa cells J. Cell Sci., November 15, 2007; 120(22): 4016 - 4024. [Abstract] [Full Text] [PDF]

				X.-Q. Gong, Q. Shao, S. Langlois, D. Bai, and D. W. Laird Differential Potency of Dominant Negative Connexin43 Mutants in Oculodentodigital Dysplasia J. Biol. Chem., June 29, 2007; 282(26): 19190 - 19202. [Abstract] [Full Text] [PDF]

				D. J. Belliveau, M. Bani-Yaghoub, B. McGirr, C. C. G. Naus, and W. J. Rushlow Enhanced Neurite Outgrowth in PC12 Cells Mediated by Connexin Hemichannels and ATP J. Biol. Chem., July 28, 2006; 281(30): 20920 - 20931. [Abstract] [Full Text] [PDF]