title: Crystal structures of wild-type and mutated cyclophilin B that causes hyperelastosis cutis in the American quarter horse.
abstract: BACKGROUND
  Hyperelastosis cutis is an inherited autosomal recessive connective tissue disorder. Affected horses are characterized by hyperextensible skin, scarring, and severe lesions along the back. The disorder is caused by a mutation in cyclophilin B.
  
  
  RESULTS
  The crystal structures of both wild-type and mutated (Gly6->Arg) horse cyclophilin B are presented. The mutation neither affects the overall fold of the enzyme nor impairs the catalytic site structure. Instead, it locally rearranges the flexible N-terminal end of the polypeptide chain and also makes it more rigid.
  
  
  CONCLUSIONS
  Interactions of the mutated cyclophilin B with a set of endoplasmic reticulum-resident proteins must be affected.
authors.affiliation: Research Department, Shriners Hospital for Children, Portland, OR 97239, USA.
authors.forename: Sergei P
authors.initials: SP
authors.lastname: Boudko
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Ishikawa
authors.forename: Thomas F
authors.initials: TF
authors.lastname: Lerch
authors.forename: Jay
authors.initials: J
authors.lastname: Nix
authors.forename: Michael S
authors.initials: MS
authors.lastname: Chapman
authors.forename: Hans Peter
authors.initials: HP
authors.lastname: Bächinger
mesh_terms: D000818:Animals; D018360:Crystallography, X-Ray; D021983:Cyclophilins / Q000737:chemistry* / Q000235:genetics*; D006734:Horse Diseases / Q000201:enzymology / Q000235:genetics*; D006736:Horses; D008958:Models, Molecular; D020125:Mutation, Missense; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D012867:Skin / Q000201:enzymology / Q000378:metabolism / Q000473:pathology; D012871:Skin Diseases / Q000201:enzymology / Q000235:genetics* / Q000662:veterinary
chemical_list: C081786:cyclophilin B; D021983:Cyclophilins