Human APE2 protein is mostly localized in the nuclei and to some extent in the mitochondria, while nuclear APE2 is partly associated with proliferating cell nuclear antigen.

ABSTRACT: In human cells APE1 is the major AP endonuclease and it has been reported to have no functional mitochondrial targeting sequence (MTS). We found that APE2 protein possesses a putative MTS. When its N-terminal 15 amino acid residues were fused to the N-terminus of green fluorescent protein and transiently expressed in HeLa cells the fusion protein was localized in the mitochondria. By electron microscopic immunocytochemistry we detected authentic APE2 protein in mitochondria from HeLa cells. Western blotting of the subcellular fraction of HeLa cells revealed most of the APE2 protein to be localized in the nuclei. We found a putative proliferating cell nuclear antigen (PCNA)-binding motif in the C-terminal region of APE2 and showed this motif to be functional by immunoprecipitation and in vi

SUBMITTER: Tsuchimoto D 

PROVIDER: S-EPMC55700 | biostudies-literature | 2001 Jun

REPOSITORIES: biostudies-literature