Connexin 32 of gap junctions contains two cytoplasmic calmodulin-binding domains.

@article{Trk1997Connexin3O,
  title={Connexin 32 of gap junctions contains two cytoplasmic calmodulin-binding domains.},
  author={Katalin T{\"o}r{\"o}k and Kathrin A. Stauffer and William Howard Evans},
  journal={The Biochemical journal},
  year={1997},
  volume={326 ( Pt 2)},
  pages={
          479-83
        }
}
A fluorescent calmodulin derivative, 2-chloro-[4-(epsilon-amino-Lys75)]-[6-(4- diethylaminophenyl)-1,3,5-triazin-4-yl]-calmodulin (TA-calmodulin) [Török and Trentham (1994) Biochemistry 33, 12807-12820], and equilibrium fluorescence methods were used to identify calmodulin-binding domains of connexin subunits of gap junctions. Synthetic peptides corresponding to six extramembrane regions of connexin 32, a major component of rat liver gap junctions, and peptides derived from connexin 43 and 26… Expand
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Evidence from spectrofluorometry and circular dichroism experiments indicates that CaM interacts with and affects the conformation of peptide C, suggesting the involvement of MIP26 C-terminal chain and CaM in gating lens junction channels. Expand
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The mechanism of the interactions of 2-chloro-(epsilon-amino-Lys75)-[6-[4-(N,N-diethylamino)phenyl]- 1,3,5-triazin-4-yl]calmodulin with smooth muscle myosin light-chain kinase (MLCK) and two 17-residue peptides and Tyr peptide was studied. Expand
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Experimental evidence indicates that, in spite of the differences in amino acid sequence, the gap junction proteins in heart and liver share a general organizational plan and that there may be several domains of the molecule that are involved in the control of junctional permeability. Expand
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TLDR
Evidence is presented to show that the twoextracellular domains of connexin32, which are important for intercellular adhesion and the insulated bridging of the extracellular space by channels allowing cell-cell communication across the gap junction, are connected by disulphide bond(s). Expand
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TLDR
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TLDR
The intramolecular disulfides linking the extracellular loops in gap junctions were shown to be present in connexins located in plasma membranes, Golgi, and a microsomal fraction, and it was concluded that the disulfide linkages were formed in the endoplasmic reticulum. Expand
Topology of the 32‐kd liver gap junction protein determined by site‐directed antibody localizations.
TLDR
Results indicate a transmembrane orientation for the protein with the amino and carboxyl termini located on the cytoplasmic side of the membrane and a model is proposed for the trans Membrane folding of the gap junction protein. Expand
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TLDR
The calmodulin binding represents the first molecular homology that has been found for junctional channel proteins from mammalian and arthropod tissues and provides a molecular basis for understanding the potential regulatory role ofCalmodulin on cell-cell communication channels in vivo. Expand
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