Connexon integrity is maintained by non-covalent bonds: intramolecular disulfide bonds link the extracellular domains in rat connexin-43.
Rat heart connexin-43 (RCx43) has been isolated using a modified procedure that is rapid and can be used with fresh or frozen hearts. When RCx43 is isolated in the presence of the alkylating reagent iodoacetamide, no intermolecular disulfide bonds are found. However, the alkylated RCx43 does have at least one intramolecular disulfide bond. By using site directed antibodies and proteolytic cleavage the location of the intramolecular disulfide bonding is shown between the two extracellular loops of RCx43.
John
S A
SA
Division of Biology, California Institute of Technology, Pasadena 91125.
Revel
J P
JP
D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies; D017630:Connexins; D004220:Disulfides / Q000032:analysis; D006801:Humans; D015151:Immunoblotting; D007460:Iodoacetamide / Q000494:pharmacology; D008565:Membrane Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D008969:Molecular Sequence Data; D009206:Myocardium / Q000378:metabolism; D010446:Peptide Fragments / Q000302:isolation & purification; D010455:Peptides / Q000138:chemical synthesis; D011487:Protein Conformation; D051381:Rats; D011919:Rats, Inbred Strains; D012689:Sequence Homology, Nucleic Acid
D000906:Antibodies; D017630:Connexins; D004220:Disulfides; D008565:Membrane Proteins; D010446:Peptide Fragments; D010455:Peptides; D007460:Iodoacetamide