A new allele, DNASE1*6, of human deoxyribonuclease I polymorphism encodes an Arg to Cys substitution responsible for its instability.
A new allele, DNASE1*6, of human deoxyribonuclease I (DNase I) has been discovered by isoelectric focusing: its gene product has the most cathodic pI of the six electrophoretic variants. Results of DNA sequencing, mismatched PCR-restriction fragment length polymorphism, and transient transfection of the variant construct showed that the mutant was caused by a C-T transition at nucleotide position 1826, resulting in an Arg to Cys substitution at amino acid position 185 of the mature enzyme. The variant isoenzyme, expressed in COS-7 cells, was more labile than the other types. Instability and an increase in the pI value of the variant suggest that a structural alteration, perhaps due to aberrant formation of a disulfide bond, could occur in the enzyme.
Yasuda
T
T
Department of Legal Medicine, Gunma University School of Medicine, Maebashi, 371-8511, Japan.
Takeshita
H
H
Iida
R
R
Kogure
S
S
Kishi
K
K
D000483:Alleles; D000595:Amino Acid Sequence; D000818:Animals; D001120:Arginine / Q000235:genetics*; D001483:Base Sequence; D019556:COS Cells; D003553:Cystine / Q000235:genetics*; D003850:Deoxyribonuclease I / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D012150:Polymorphism, Restriction Fragment Length; D013997:Time Factors
D003553:Cystine; D001120:Arginine; D003850:Deoxyribonuclease I