title: Cloning, sequence analysis and phylogeny of connexin43 isolated from American black bear heart.
abstract: Conduction in the heart requires gap junctions. In mammalian ventricular myocytes these consist of connexin43 (Cx43). Hearts of non-hibernating species display conduction disturbances at reduced temperatures. These may exacerbate into lethal arrhythmias. Hibernating species are protected against these arrhythmias by a non-resolved mechanism. To analyze whether the amino acid composition of Cx43 from the hibernating American black bear displays specific features, we cloned the full coding sequence of Ursus americanus Cx43 and compared with that of other (non)hibernating species. UaCx43 displays 99.7% identity to rabbit Cx43 at the amino acid level. No specific features were observed in UaCx43 when compared to previously cloned Cx43 from hibernating and non-hibernating mammals. Phylogenetic tree reconstruction of this and other published full-length Cx43 sequences reveals a very high level of conservation from fish to men. Finally, one of the previously identified six mammalian characteristic amino acids, is not conserved in the black bear.
authors.affiliation: Department of Medical Physiology, Heart Lung Center Utrecht, University Medical Center Utrecht, Utrecht, The Netherlands. m.a.g.vanderheyden@umcutrecht.nl
authors.forename: Marcel A G
authors.initials: MA
authors.lastname: Van Der Heyden
authors.forename: Bart
authors.initials: B
authors.lastname: Kok
authors.forename: Evelyn N
authors.initials: EN
authors.lastname: Kouwenhoven
authors.forename: Øivind
authors.initials: Ø
authors.lastname: Tøien
authors.forename: Brian M
authors.initials: BM
authors.lastname: Barnes
authors.forename: Vadim G
authors.initials: VG
authors.lastname: Fedorov
authors.forename: Igor R
authors.initials: IR
authors.lastname: Efimov
authors.forename: Tobias
authors.initials: T
authors.lastname: Opthof
mesh_terms: D000569:Americas; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001831:Body Temperature; D003001:Cloning, Molecular; D018031:Connexin 43 / Q000235:genetics* / Q000302:isolation & purification*; D017124:Conserved Sequence; D018076:DNA, Complementary; D006352:Heart Ventricles; D006605:Hibernation; D008297:Male; D008969:Molecular Sequence Data; D009206:Myocardium / Q000378:metabolism*; D010802:Phylogeny; D020033:Protein Isoforms; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D001503:Ursidae
chemical_list: D018031:Connexin 43; D018076:DNA, Complementary; D020033:Protein Isoforms