Gap junctions: structure and function (Review)

@article{Evans2002GapJS,
  title={Gap junctions: structure and function (Review)},
  author={William Howard Evans and Patricia E M Martin},
  journal={Molecular Membrane Biology},
  year={2002},
  volume={19},
  pages={121 - 136}
}
Gap junctions are plasma membrane spatial microdomains constructed of assemblies of channel proteins called connexins in vertebrates and innexins in invertebrates. The channels provide direct intercellular communication pathways allowing rapid exchange of ions and metabolites up to ~1 kD in size. Approximately 20 connexins are identified in the human or mouse genome, and orthologues are increasingly characterized in other vertebrates. Most cell types express multiple connexin isoforms, making… Expand
Incorporation of connexins into plasma membranes and gap junctions.
TLDR
A large number of mutations in Cx26 and Cx32 detected in genetic diseases have emphasised the requirement for precise oligomerisation of connexins into hexameric connexons that traffic to the plasma membrane. Expand
Evolutionary analyses of gap junction protein families.
TLDR
The degree of evolutionary conservation was mapped onto the 3D structure of a connexon (i.e. the assembly of six connexins) and independent phylogenies of pannexins and connexin families were reconstructed using probabilistic methods of inference. Expand
Plasma membrane channels formed by connexins: their regulation and functions.
TLDR
The physiological role of gap junctions in several tissues has been elucidated by the discovery of mutant connexins associated with genetic diseases and by the generation of mice with targeted ablation of specific connexin genes. Expand
Interactions of connexins with other membrane channels and transporters.
TLDR
Evidence supporting interactions between Cx and membrane channels/transporters including CFTR, aquaporins, ionotropic glutamate receptors, and between pannexin1, another class of putative gap-junction-forming proteins, and Kvbeta3, a regulatory beta-subunit of voltage gated potassium channels are discussed. Expand
The effector and scaffolding proteins AF6 and MUPP1 interact with connexin36 and localize at gap junctions that form electrical synapses in rodent brain
TLDR
The present results suggest that AF6 may be a target for cAMP/Epac/Rap1 signalling at electrical synapses, and that MUPP1 may contribute to anchoring CaMKII at these synapses. Expand
Connexins and cell signaling in development and disease.
  • C. Wei, X. Xu, C. Lo
  • Biology, Medicine
  • Annual review of cell and developmental biology
  • 2004
TLDR
Gap junctions contain hydrophilic membrane channels that allow direct communication between neighboring cells through the diffusion of ions, metabolites, and small cell signaling molecules, and are likely to be important in the role of gap junctions in development and disease. Expand
Innexins: members of an evolutionarily conserved family of gap-junction proteins.
  • P. Phelan
  • Biology, Medicine
  • Biochimica et biophysica acta
  • 2005
TLDR
Genetic manipulation of innexin function in relatively simple cellular systems should speed progress not only in defining the importance of gap junctions in a variety of biological processes but also in elucidating the mechanisms by which they act. Expand
Gap junction channel protein innexin 2 is essential for epithelial morphogenesis in the Drosophila embryo.
TLDR
The function and the distribution of Drosophila Innexin 2 protein in embryonic epithelia are examined and biochemical interaction studies together with genetic loss- and gain-of-function experiments provide evidence that InnexIn 2 interacts with core proteins of adherens and septate junctions. Expand
Expression and functions of neuronal gap junctions
TLDR
The roles of connexin and pannexin genes in the formation of neuronal gap junctions are discussed, and recent functional analyses of electrical synapses that became possible through the characterization of mouse mutants that show targeted defects in con Nexin genes are evaluated. Expand
Connexins in leukocytes: shuttling messages?
TLDR
The potential physiological roles of gap junctions in the development and recruitment of leukocytes as well as in the regulation of the immune response and the importance of GJIC in immuno-inflammatory pathologies is illustrated in atherosclerosis. Expand
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 209 REFERENCES
Chapter 2: Degradation of Gap Junctions and Connexins
TLDR
It is not clear a priori which proteolytic organelles would degrade the connexins, but it remains to be seen whether they are degraded by the same mechanism. Expand
Connexins, connexons, and intercellular communication.
TLDR
Structural-function studies provide a molecular understanding of the significance of connexin diversity and demonstrate the unique regulation of Connexins by tyrosine kinases and oncogenes. Expand
Three-dimensional structure of the gap junction connexon.
TLDR
The implication of the hemichannel structure is discussed in relation to the in vivo state of unpaired connexons, which have been shown to exist in the plasma membrane. Expand
Connexin mimetic peptides: specific inhibitors of gap-junctional intercellular communication.
TLDR
Connexin mimetic peptides that correspond to short specific sequences in the two extracellular loops of connexins are a class of benign, specific and reversible inhibitors of gap-junctional communication that have been studied recently in a broad range of cells, tissues and organs. Expand
Membrane integration of in vitro-translated gap junctional proteins: co- and post-translational mechanisms.
TLDR
It is observed that both Cx32 and Cx26 could insert into microsome membranes co-translationally, producing a topological structure indistinguishable from that in isolated gap junctions, raising the possibility that there may be another pathway for Cx 26 to insert into membranes in cells and this feature may be important for the regulation of its functions. Expand
Structural and Functional Diversity of Connexin Genes in the Mouse and Human Genome
TLDR
This review compares currently identified connexin genes in both the mouse and human genome and discusses the functions of gap junctions deduced from targeted mouse mutants and human genetic disorders. Expand
Structure of gap junction intercellular channels.
TLDR
A three-dimensional analysis based on images recorded from tilted crystals should reveal the location and secondary structure of additional transmembrane domains, as well as provide important structural details about the interactions between connexins within a hemi-channel and connexon-connexon interactions in the extracellular gap. Expand
Assembly of gap junction channels
TLDR
Results indicate that amino-acid sequences in the third transmembrane domain and a calmodulin-binding domain in the cytoplasmic tail of Cx32 are likely candidates for regulating connexin oligomerization. Expand
Regulation of gap junctions by phosphorylation of connexins.
  • P. Lampe, A. Lau
  • Biology, Medicine
  • Archives of biochemistry and biophysics
  • 2000
TLDR
This review examines the consequences of connexin phosphorylation for the regulation of gap junctional communication. Expand
Post-translational integration and oligomerization of connexin 26 in plasma membranes and evidence of formation of membrane pores: implications for the assembly of gap junctions.
TLDR
It is demonstrated that connexin (Cx) 26, one of the smallest connexins, is integrated directly in a post-translational manner into plasma membranes and oligomerizes and provides permeability to ascorbic acid, suggesting that gap-junction hemichannels are generated. Expand
...
1
2
3
4
5
...