Molecular cloning and functional expression of mouse connexin-30,a gap junction gene highly expressed in adult brain and skin.
A new gap junction gene isolated from the mouse genome codes for a connexin protein of 261 amino acids. Because of its theoretical molecular mass of 30.366 kDa, it is named connexin-30. Within the connexin gene family, this protein is most closely related to connexin-26 (77% amino acid sequence identity). The coding region of mouse connexin-30 is uninterrupted by introns and is detected in the mouse genome as a single copy gene that is assigned to mouse chromosome 14 by analysis of mouse x hamster somatic cell hybrids. Abundant amounts of connexin-30 mRNA (two transcripts of 2.0 and 2.3 kilobase pairs) were found after 4 weeks of postnatal development in mouse brain and skin. Microinjection of connexin-30 cRNA into Xenopus oocytes induced formation of functional gap junction channels that gated somewhat asymmetrically in response to transjunctional voltage and at significantly lower voltage (Vo = +38 and -46 mV) than the closely homologous connexin-26 channels (Vo = 89 mV). Heterotypic pairings of connexin-30 with connexin-26 and connexin-32 produced channels with highly asymmetric and rectifying voltage gating, respectively. This suggests that the polarity of voltage gating and the cationic selectivity of connexin-30 are similar to those of its closest homologue, connexin-26.
Dahl
E
E
Institut für Genetik, Abteilung Molekulargenetik, Universität Bonn, 53117 Bonn, Federal Republic of Germany.
Manthey
D
D
Chen
Y
Y
Schwarz
H J
HJ
Chang
Y S
YS
Lalley
P A
PA
Nicholson
B J
BJ
Willecke
K
K
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001921:Brain / Q000254:growth & development; D001923:Brain Chemistry / Q000235:genetics*; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D000075302:Connexin 30; D017630:Connexins / Q000145:classification / Q000235:genetics*; D004553:Electric Conductivity; D017629:Gap Junctions / Q000235:genetics* / Q000378:metabolism; D015870:Gene Expression; D016678:Genome; D051379:Mice; D008969:Molecular Sequence Data; D010802:Phylogeny; D014176:Protein Biosynthesis; D012333:RNA, Messenger / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D012867:Skin / Q000737:chemistry*; D014018:Tissue Distribution; D014981:Xenopus; D029867:Xenopus Proteins; D000097002:Gap Junction beta-1 Protein
D000075302:Connexin 30; D017630:Connexins; D012333:RNA, Messenger; D029867:Xenopus Proteins; D000097002:Gap Junction beta-1 Protein; C100629:Gjb6 protein, mouse