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Am J Physiol Cell Physiol
2013 Jun 15;30412:C1150-8. doi: 10.1152/ajpcell.00374.2012.
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The human Cx26-D50A and Cx26-A88V mutations causing keratitis-ichthyosis-deafness syndrome display increased hemichannel activity.
Mhaske PV, Levit NA, Li L, Wang HZ, Lee JR, Shuja Z, Brink PR, White TW.
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Mutations in the human gene encoding connexin 26 (Cx26 or GJB2) cause either nonsyndromic deafness or syndromic deafness associated with skin diseases. That distinct clinical disorders can be caused by different mutations within the same gene suggests that different channel activities influence the ear and skin. Here we use three different expression systems to examine the functional characteristics of two Cx26 mutations causing either mild (Cx26-D50A) or lethal (Cx26-A88V) keratitis-ichthyosis-deafness (KID) syndrome. In either cRNA-injected Xenopus oocytes, transfected HeLa cells, or transfected primary human keratinocytes, we show that both Cx26-D50A and Cx26-A88V form active hemichannels that significantly increase membrane current flow compared with wild-type Cx26. This increased membrane current accelerated cell death in low extracellular calcium solutions and was not due to increased mutant protein expression. Elevated mutant hemichannel currents could be blocked by increased extracellular calcium concentration. These results show that these two mutations exhibit a shared gain of functional activity and support the hypothesis that increased hemichannel activity is a common feature of human Cx26 mutations responsible for KID syndrome.
Barrio,
Gap junctions formed by connexins 26 and 32 alone and in combination are differently affected by applied voltage.
1991, Pubmed,
Xenbase
Barrio,
Gap junctions formed by connexins 26 and 32 alone and in combination are differently affected by applied voltage.
1991,
Pubmed
,
Xenbase Bruzzone,
Connexin40, a component of gap junctions in vascular endothelium, is restricted in its ability to interact with other connexins.
1993,
Pubmed
,
Xenbase Bruzzone,
Connections with connexins: the molecular basis of direct intercellular signaling.
1996,
Pubmed Chandrasekhar,
Hemichannels: permeants and their effect on development, physiology and death.
2012,
Pubmed Chi,
Pathogenic connexin-31 forms constitutively active hemichannels to promote necrotic cell death.
2012,
Pubmed Cushing,
Successful cochlear implantation in a child with Keratosis, Icthiosis and Deafness (KID) Syndrome and Dandy-Walker malformation.
2008,
Pubmed del Castillo,
The DFNB1 subtype of autosomal recessive non-syndromic hearing impairment.
2011,
Pubmed DeVries,
Hemi-gap-junction channels in solitary horizontal cells of the catfish retina.
1992,
Pubmed Donnelly,
Differential susceptibility of Cx26 mutations associated with epidermal dysplasias to peptidoglycan derived from Staphylococcus aureus and Staphylococcus epidermidis.
2012,
Pubmed Duman,
Autosomal recessive nonsyndromic deafness genes: a review.
2012,
Pubmed Ebihara,
Properties of a nonjunctional current expressed from a rat connexin46 cDNA in Xenopus oocytes.
1993,
Pubmed
,
Xenbase Essenfelder,
Connexin30 mutations responsible for hidrotic ectodermal dysplasia cause abnormal hemichannel activity.
2004,
Pubmed
,
Xenbase Gerido,
Aberrant hemichannel properties of Cx26 mutations causing skin disease and deafness.
2007,
Pubmed
,
Xenbase González,
Species specificity of mammalian connexin-26 to form open voltage-gated hemichannels.
2006,
Pubmed
,
Xenbase Haruna,
Severe form of keratitis-ichthyosis-deafness (KID) syndrome associated with septic complications.
2010,
Pubmed Horton,
Gene splicing by overlap extension: tailor-made genes using the polymerase chain reaction.
1990,
Pubmed Iossa,
GJB2 Gene Mutations in Syndromic Skin Diseases with Sensorineural Hearing Loss.
2011,
Pubmed Jonard,
A familial case of Keratitis-Ichthyosis-Deafness (KID) syndrome with the GJB2 mutation G45E.
2008,
Pubmed Kar,
Biological role of connexin intercellular channels and hemichannels.
2012,
Pubmed Koppelhus,
A novel mutation in the connexin 26 gene (GJB2) in a child with clinical and histological features of keratitis-ichthyosis-deafness (KID) syndrome.
2011,
Pubmed Koval,
Drowning out communication. Focus on "The human Cx26-D50A and Cx26-A88V mutations causing keratitis-ichthyosis-deafness syndrome display increased hemichannel activity".
2013,
Pubmed Lee,
Connexin mutations causing skin disease and deafness increase hemichannel activity and cell death when expressed in Xenopus oocytes.
2009,
Pubmed
,
Xenbase Lee,
Connexin-26 mutations in deafness and skin disease.
2009,
Pubmed Levit,
Pathological hemichannels associated with human Cx26 mutations causing Keratitis-Ichthyosis-Deafness syndrome.
2012,
Pubmed
,
Xenbase Malchow,
Evidence for hemi-gap junctional channels in isolated horizontal cells of the skate retina.
1993,
Pubmed Mauro,
Extracellular calcium affects the membrane currents of cultured human keratinocytes.
1990,
Pubmed Mazereeuw-Hautier,
Keratitis-ichthyosis-deafness syndrome: disease expression and spectrum of connexin 26 (GJB2) mutations in 14 patients.
2007,
Pubmed Mese,
The Cx26-G45E mutation displays increased hemichannel activity in a mouse model of the lethal form of keratitis-ichthyosis-deafness syndrome.
2011,
Pubmed Meşe,
Connexin26 deafness associated mutations show altered permeability to large cationic molecules.
2008,
Pubmed Meşe,
Altered gating properties of functional Cx26 mutants associated with recessive non-syndromic hearing loss.
2004,
Pubmed
,
Xenbase Meşe,
Gap junctions: basic structure and function.
2007,
Pubmed Montgomery,
A novel connexin 26 gene mutation associated with features of the keratitis-ichthyosis-deafness syndrome and the follicular occlusion triad.
2004,
Pubmed
,
Xenbase Pfahnl,
Gating of cx46 gap junction hemichannels by calcium and voltage.
1999,
Pubmed
,
Xenbase Pfenniger,
Mutations in connexin genes and disease.
2011,
Pubmed Richard,
Connexin disorders of the skin.
2005,
Pubmed Richard,
Missense mutations in GJB2 encoding connexin-26 cause the ectodermal dysplasia keratitis-ichthyosis-deafness syndrome.
2002,
Pubmed Ripps,
Properties of connexin26 hemichannels expressed in Xenopus oocytes.
2004,
Pubmed
,
Xenbase Sánchez,
Differentially altered Ca2+ regulation and Ca2+ permeability in Cx26 hemichannels formed by the A40V and G45E mutations that cause keratitis ichthyosis deafness syndrome.
2010,
Pubmed
,
Xenbase Sbidian,
Germline mosaicism in keratitis-ichthyosis-deafness syndrome: pre-natal diagnosis in a familial lethal form.
2010,
Pubmed Scott,
Key functions for gap junctions in skin and hearing.
2011,
Pubmed Skinner,
The keratitis, ichthyosis, and deafness (KID) syndrome.
1981,
Pubmed Stong,
A novel mechanism for connexin 26 mutation linked deafness: cell death caused by leaky gap junction hemichannels.
2006,
Pubmed Terrinoni,
Connexin 26 (GJB2) mutations, causing KID Syndrome, are associated with cell death due to calcium gating deregulation.
2010,
Pubmed Turner,
Expression of achaete-scute homolog 3 in Xenopus embryos converts ectodermal cells to a neural fate.
1994,
Pubmed
,
Xenbase van Steensel,
A novel connexin 26 mutation in a patient diagnosed with keratitis-ichthyosis-deafness syndrome.
2002,
Pubmed White,
Genetic diseases and gene knockouts reveal diverse connexin functions.
1999,
Pubmed White,
Mouse Cx50, a functional member of the connexin family of gap junction proteins, is the lens fiber protein MP70.
1992,
Pubmed
,
Xenbase White,
Functional analysis of human Cx26 mutations associated with deafness.
2000,
Pubmed
,
Xenbase Wohlrab,
Electrophysiological characterization of human keratinocytes using the patch-clamp technique.
2000,
Pubmed Xu,
The role of connexins in ear and skin physiology - functional insights from disease-associated mutations.
2013,
Pubmed Zhao,
Gap junctions and cochlear homeostasis.
2006,
Pubmed