Structural and expression analyses of normal and mutant mRNA encoding glycine decarboxylase: three-base deletion in mRNA causes nonketotic hyperglycinemia.
Full-length cDNA clone encoding human glycine decarboxylase (P-protein) was isolated from the human placental lambda gt11 expression library using specific antibodies. This clone was 3,705 bp in length and encoded 1,020 amino acids. We studied the structure of the mutant P-protein mRNA expressed in the liver of a patient with nonketotic hyperglycinemia (NKH) deficient of P-protein. A three-base deletion, which resulted in deletion of Phe756, was found. Cos7 cells in which normal P-protein cDNA was expressed presented an activity of 6.9 +/- 0.41 nmole/milligram of protein/hour, which was almost equivalent to that of human liver. In contrast, Cos7 cells in which the mutant cDNA was expressed showed no activity, indicating that the three-base deletion could cause NKH.
Kure
S
S
Department of Biochemical Genetics, Tohoku University School of Medicine, Sendai, Japan.
Narisawa
K
K
Tada
K
K
D000592:Amino Acid Metabolism, Inborn Errors / Q000201:enzymology / Q000235:genetics*; D000594:Amino Acid Oxidoreductases / Q000235:genetics*; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D002460:Cell Line; D002675:Child, Preschool; D002872:Chromosome Deletion; D050841:Glycine Dehydrogenase (Decarboxylating); D006801:Humans; D008099:Liver / Q000201:enzymology*; D008297:Male; D008969:Molecular Sequence Data; D009154:Mutation; D015345:Oligonucleotide Probes; D016133:Polymerase Chain Reaction / Q000379:methods; D012333:RNA, Messenger / Q000235:genetics*; D012016:Reference Values; D014162:Transfection
D015345:Oligonucleotide Probes; D012333:RNA, Messenger; D000594:Amino Acid Oxidoreductases; D050841:Glycine Dehydrogenase (Decarboxylating)