Determination of functional effects of mutations in the steroid 21-hydroxylase gene (CYP21) using recombinant vaccinia virus. J Biol Chem 1990 Dec 05;265(34):20916-22
Date
12/05/1990Pubmed ID
2249999Scopus ID
2-s2.0-0025696003 (requires institutional sign-in at Scopus site) 244 CitationsAbstract
Steroid 21-hydroxylase (P450c21) is absent or defective in more than 90% of patients with congenital adrenal hyperplasia. This disorder of cortisol biosynthesis occurs in a wide spectrum of clinical severity; specific mutations in the 21-hydroxylase gene (CYP21) have been found in association with particular clinical phenotypes. To determine the functional effects of mutations causing amino acid substitutions, normal P450c21 and three mutagenized P450c21 enzymes were expressed at high levels in cultured COS-1 cells using recombinant vaccinia virus. A single amino acid substitution (Val281----Leu) present in patients with mild "nonclassical" 21-hydroxylase deficiency resulted in an enzyme with 20-50% of normal activity. A mutation (Ile172----Asn) identified in patients with the "simple virilizing" form (poor cortisol synthesis but adequate aldosterone synthesis) resulted in an enzyme with less than 2% of normal activity. Finally, a cluster mutation (Ile-Val-Glu-Met234-238----Asn-Glu-Glu-Lys) found in a patient with severe "salt wasting" 21-hydroxylase deficiency (inadequate aldosterone synthesis) results in an enzyme with no detectable activity. These data indicate that the severity of 21-hydroxylase deficiency correlates with the degree of enzymatic compromise.
Author List
Tusie-Luna MT, Traktman P, White PCMESH terms used to index this publication - Major topics in bold
Amino Acid SequenceAnimals
Base Sequence
DNA
Humans
Kinetics
Microsomes
Molecular Sequence Data
Mutagenesis, Site-Directed
Oligonucleotide Probes
Plasmids
Recombinant Proteins
Recombination, Genetic
Steroid 21-Hydroxylase
Subcellular Fractions
Transfection
Vaccinia virus
