Human red cell acid phosphatase (ACP1): the primary structure of the two pairs of isozymes encoded by the ACP1*A and ACP1*C alleles.
The Af, As, Cf and Cs isozymes encoded by the human red cell acid phosphatase ACP1*A and ACP1*C alleles, respectively, have been sequenced. All four isozymes consist of a single non-glycosylated peptide chain (157 residues), acetylated at the amino-terminal alanine residue. Each f isozyme differs from the corresponding s isozyme over the sequence segment 40-73, while the remaining four-fifth of the molecules are identical. These findings are consistent with results for the Bf and Bs isozymes encoded by the common ACP1*B allele and confirm that the presence of a specific f or s segment is a common property to ACP1 isozymes. This supports our hypothesis that f and s isozymes are generated by alternative splicing of exons in the primary RNA transcript. Cf and Cs are identical in sequence with Bf and Bs, respectively. Thus, the ACP1*B and ACP1*C alleles encode exactly the same pair of isozymes, the only difference at the protein level being the ratio of f and s isozyme. Af and As differ from the Bf and Bs isozymes by a single substitution at residue 105; Arg and Gln, respectively. These observations explain the electrophoretic identity of the B and C isozyme pairs and the higher P(i) of the A isozyme pair.
Dissing
J
J
Institute of Forensic Genetics, University of Copenhagen, Denmark.
Johnsen
A H
AH
D000135:Acid Phosphatase / Q000737:chemistry / Q000235:genetics*; D000483:Alleles; D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D004912:Erythrocytes / Q000201:enzymology*; D006801:Humans; D007527:Isoenzymes / Q000737:chemistry / Q000235:genetics*; D008969:Molecular Sequence Data
D000596:Amino Acids; D007527:Isoenzymes; D000135:Acid Phosphatase