Oligomeric Structure and Functional Characterization of Caenorhabditis elegans Innexin-6 Gap Junction Protein

Oshima, Atsunori; Matsuzawa, Tomohiro; Nishikawa, Kyoji; Fujiyoshi, Yoshinori

doi:10.1074/jbc.m112.428383

Cited by 32 publications

(55 citation statements)

References 63 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…According to our previous work [20], wild-type (WT) INX-6 channels were first purified in 0.1% octyl glucose neopentyl glycol solution (Fig. 1a).…”

Section: Two-dimensional Crystallization Of Inx-6 Channelsmentioning

confidence: 99%

“…Findings from crosslinking and native gel studies suggested that rat pannexin2, a vertebrate innexin homolog protein, forms heptameric or octameric channels [19]. Our recent electron microscopy (EM) study with negative staining of Caenorhabditis elegans innexin-6 (INX-6) channels demonstrated that oligomeric junction channels have larger external dimensions than Cx26 channels [20].…”

Section: Introductionmentioning

confidence: 97%

See 1 more Smart Citation

Hexadecameric structure of an invertebrate gap junction channel

Oshima

Matsuzawa

Murata

et al. 2016

Journal of Molecular Biology

Self Cite

View full text Add to dashboard Cite

Innexins are invertebrate-specific gap junction proteins with four transmembrane helices. These proteins oligomerize to constitute intercellular channels that allow for the passage of small signaling molecules associated with neural and muscular electrical activity. In contrast to the large number of structural and functional studies of connexin gap junction channels, few structural studies of recombinant innexin channels are reported. Here we show the three-dimensional structure of two-dimensionally crystallized Caenorhabditis elegans innexin-6 (INX-6) gap junction channels. The N-terminal deleted INX-6 proteins are crystallized in lipid bilayers. The three-dimensional reconstruction determined by cryo-electron crystallography reveals that a single INX-6 gap junction channel comprises 16 subunits, a hexadecamer, in contrast to chordate connexin channels, which comprise 12 subunits. The channel pore diameters at the cytoplasmic entrance and extracellular gap region are larger than those of connexin26. Two bulb densities are observed in each hemichannel, one in the pore and the other at the cytoplasmic side of the hemichannel in the channel pore pathway. These findings imply a structural diversity of gap junction channels among multicellular organisms.

show abstract

“…According to our previous work [20], wild-type (WT) INX-6 channels were first purified in 0.1% octyl glucose neopentyl glycol solution (Fig. 1a).…”

Section: Two-dimensional Crystallization Of Inx-6 Channelsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 97%

Hexadecameric structure of an invertebrate gap junction channel

Oshima

Matsuzawa

Murata

et al. 2016

Journal of Molecular Biology

Self Cite

View full text Add to dashboard Cite

show abstract

“…Connexins and innexins reportedly evolved convergently (44) but are surprisingly similar in their topology and function (1,12). Innexin channels generally have a larger outer diameter (12,42), consistent with looser packing of TM domains.…”

Section: Discussionmentioning

confidence: 84%

“…Important elements of the pore include a hinged plug within the cytoplasmic vestibule of the channel, induced by an infolded N-terminal helix and a short 3 10 helix at the extracellular end, which is formed by EL1 (10). These important pore features are supported by three-dimensional projection structures (11,12) and molecular dynamic refinements (13,14).…”

mentioning

confidence: 74%

See 1 more Smart Citation

Tryptophan Scanning Reveals Dense Packing of Connexin Transmembrane Domains in Gap Junction Channels Composed of Connexin32

Brennan

Karcz

Vaughn

et al. 2015

Journal of Biological Chemistry

View full text Add to dashboard Cite

Background: Transmembrane domain interactions in gap junction channels are poorly understood. Results: Tryptophan substitution experiments involving all four TM domains of Cx32 revealed tight packing. Conclusion: After modeling, tight packing was found to occur in the midregion. Pore-facing residues were highly sensitive to substitution, whereas lipid-facing residues were variably tolerant. Significance: Connexin-based channels are more densely packed than their innexin-based counterparts.

show abstract

Gap junctions in C. elegans: Their roles in behavior and development

Hall

2016

Developmental Neurobiology

View full text Add to dashboard Cite

The nematode Caenorhabditis elegans utilizes gap junctions in different fashions in virtually all of its cells. This model animal has a surprisingly large number of innexin genes within its genome, and many nematode cell types can express multiple innexins at once, leading to the formation of diverse junction types and enough redundancy to limit the effect of single gene knockdowns on animal development or behavioral phenotypes. Here, we review the general properties of these junctions, their expression patterns, and their known roles in tissue development and in the animal's connectome. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 587–596, 2017

show abstract

Oligomeric Structure and Functional Characterization of Caenorhabditis elegans Innexin-6 Gap Junction Protein

Cited by 32 publications

References 63 publications

Hexadecameric structure of an invertebrate gap junction channel

Hexadecameric structure of an invertebrate gap junction channel

Tryptophan Scanning Reveals Dense Packing of Connexin Transmembrane Domains in Gap Junction Channels Composed of Connexin32

Gap junctions in C. elegans: Their roles in behavior and development

Contact Info

Product

Resources

About