Izumi T, Mitra S
Sealy Center for Molecular Science and Department of Human Biological Chemistry and Genetics, University of Texas Medical Branch, Galveston 77555-1079, USA.
Carcinogenesis. 1998 Mar;19(3):525-7. doi: 10.1093/carcin/19.3.525.
AP-endonuclease (APE) plays a central role in the base excision repair process for oxidative and alkylation damage in DNA. The major human APE with 318 amino acid residues possesses transcriptional regulatory activities for which the N-terminal region was found to be essential. Systematic deletion studies of both amino and carboxyl termini of the human APE have shown that the carboxyl termini residues are essential for the endonuclease activity as indicated by direct measurement of enzyme activity and from studies on phenotypic rescue of Escherichia coli. However, the amino-terminal residues are dispensable for this activity and the boundary of the active endonuclease lies at this end between positions 61 and 80.
脱嘌呤嘧啶内切核酸酶（APE）在DNA氧化损伤和烷基化损伤的碱基切除修复过程中起着核心作用。主要的人类APE有318个氨基酸残基，具有转录调控活性，其中N端区域被认为是必不可少的。对人类APE的氨基和羧基末端进行的系统缺失研究表明，通过直接测量酶活性以及对大肠杆菌表型拯救的研究表明，羧基末端残基对于内切核酸酶活性至关重要。然而，氨基末端残基对于这种活性是可有可无的，活性内切核酸酶的边界位于该末端的第61位和第80位之间。
