Identification of the specific labile sites in the 180 kDa catalytic polypeptide of the Drosophila melanogaster DNA polymerase alpha-primase complex.
J Biochem
; 113(2): 126-8, 1993 Feb.
Article
em En
| MEDLINE
| ID: mdl-8468316
ABSTRACT
The immunoaffinity-purified DNA polymerase alpha-primase complex from Drosophila melanogaster Kc cells contains three high molecular weight polypeptides besides the 180 kDa catalytic polypeptide. These polypeptides are immunologically cross-reactive with the 180 kDa polypeptide. When the immunoaffinity-purified complex was kept at 4 degrees C for about four weeks, the amounts of the three polypeptides increased, while the 180 kDa polypeptide completely disappeared. Sodium bisulfite inhibited the decrease in the 180 kDa polypeptide. The N-terminal amino acid sequences of all the polypeptides were all assigned to ones present in a portion close to the N-terminus of the 180 kDa polypeptide. The N-terminal residue of all the three polypeptides was Ser. The cleavage sites were Phe130-Ser131, Thr180-Ser181, and Phe237-Ser238. These results show that the three polypeptides are cleavage products of the 180 kDa catalytic polypeptide, the cleavage occurring at specific labile sites including a Ser residue. The amino acid residues at the sites are quite different from those (Lys-Lys) in the human 180 kDa catalytic polypeptide.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
RNA Nucleotidiltransferases
Tipo de estudo:
Diagnostic_studies
Limite:
Animals
Idioma:
En
Revista:
J Biochem
Ano de publicação:
1993
Tipo de documento:
Article