Journal
JOURNAL OF NEUROSCIENCE RESEARCH
Volume 86, Issue 5, Pages 992-1006Publisher
WILEY
DOI: 10.1002/jnr.21561
Keywords
Schwann cells; oligodendrocytes; gap junctions; myelin; mutations
Categories
Funding
- NINDS NIH HHS [R01 NS055284-02, R01 NS055284, K02 NS050345-03, K02 NS050345, R01 NS043560, NS43560, R01 NS042878, NS42878, K02 NS050345-02, P30 NS047321] Funding Source: Medline
Ask authors/readers for more resources
In rodents, oligodendrocytes and myelinating Schwann cells express connexin32 (Cx32) and Cx29, which have different localizations in the two cell types. We show here that, in contrast to Cx32, Cx29 does not form gap junction plaques or functional gap junctions in transfected cells. Furthermore, when expressed together, Cx29 and Cx32 are not colocalized and do not coimmunoprecipitate. To determine the structural basis of their divergent behavior, we generated a series of chimeric Cx32-Cx29 proteins by exchanging their intracellular loops and/or their C-terminal cytoplasmic tails. Although some chimerae reach the cell membrane, others appear to be largely localized intracellularly; none form gap junction plaques or functional gap junctions. Substituting the C-terminus or the intracellular loop and the C-terminus of Cx32 with those of Cx29 does not disrupt their colocalization or coimmunoprecipitation with Cx32. Substituting the C-terminus of Cx29 with that of Cx32 does not disrupt the coimmunoprecipitation or the colocalization with Cx29, whereas substituting both the intracellular loop and the C-terminus of Cx32 with those of Cx29 diminishes the coimmunoprecipitation with Cx29. Conversely, the Cx32 chimera that contains the intracellular loop of Cx29 coimmunoprecipitates with Cx29, indicating that the intracellular loop participates in Cx29-Cx29 interactions. These data indicate that homomeric interactions of Cx29 and especially Cx32 largely require other domains: the N-terminus, transmembrane domains, and extracellular loops. Substituting the intracellular loop and/or tail of Cx32 with those of Cx29 appears to prevent Cx32 from forming functional gap junctions. (C) 2007 Wiley-Liss, Inc.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available