APEX1

Gene Symbol APEX1
Entrez Gene 328
Alt Symbol APE, APE1, APEN, APEX, APX, HAP1, REF1
Species Human
Gene Type protein-coding
Description APEX nuclease (multifunctional DNA repair enzyme) 1
Other Description AP endonuclease class I|AP lyase|DNA-(apurinic or apyrimidinic site) lyase|apurinic-apyrimidinic endonuclease 1|apurinic/apyrimidinic (abasic) endonuclease|deoxyribonuclease (apurinic or apyrimidinic)|protein REF-1|redox factor-1
Swissprots Q99775 Q969L5 P27695
Accessions AAA58373 AAA58629 AAL86909 BAA02633 CAA46925 EAW66463 EAW66464 EAW66465 EAW66466 EAW66467 EAW66468 P27695 AI554786 AK098588 AK291100 BAF83789 AK311548 BC002338 AAH02338 BC004979 AAH04979 BC008145 AAH08145 BC019291 AAH19291 BC095428 AAH95428 BT007236 AAP35900 BT020133 AAV38935 BX161454 CAD61917 CB139337 D90373 BAA14381 DQ891814 ABM82740 DQ894998 ABM85924 M80261 AAA58371 M81955 AAA58372 S43127 AAB22977 U79268 AAB50212 X59764 CAA42437 XM_005267581 XP_005267638 XM_005267582 XP_005267639 NM_001244249 NP_001231178 NM_001641 NP_001632 NM_080648 NP_542379 NM_080649 NP_542380
Function Multifunctional protein that plays a central role in the cellular response to oxidative stress. The two major activities of APEX1 in DNA repair and redox regulation of transcriptional factors. Functions as a apurinic/apyrimidinic (AP) endodeoxyribonuclease in the DNA base excision repair (BER) pathway of DNA lesions induced by oxidative and alkylating agents. Initiates repair of AP sites in DNA by catalyzing hydrolytic incision of the phosphodiester backbone immediately adjacent to the damage, generating a single-strand break with 5'-deoxyribose phosphate and 3'-hydroxyl ends. Does also incise at AP sites in the DNA strand of DNA/RNA hybrids, single-stranded DNA regions of R-loop structures, and single-stranded RNA molecules. Has a 3'-5' exoribonuclease activity on mismatched deoxyribonucleotides at the 3' termini of nicked or gapped DNA molecules during short-patch BER. Possesses a DNA 3' phosphodiesterase activity capable of removing lesions (such as phosphoglycolate) blocking the 3'
Subcellular Location Nucleus. Nucleus, nucleolus. Nucleus speckle. Endoplasmic reticulum. Cytoplasm. Note=Detected in the cytoplasm of B-cells stimulated to switch (By similarity). Colocalized with SIRT1 in the nucleus. Colocalized with YBX1 in nuclear speckles after genotoxic stress. Together with OGG1 is recruited to nuclear speckles in UVA-irradiated cells. Colocalized with nucleolin and NPM1 in the nucleolus. Its nucleolar localization is cell cycle dependent and requires active rRNA transcription. Colocalized with calreticulin in the endoplasmic reticulum. Translocation from the nucleus to the cytoplasm is stimulated in presence of nitric oxide (NO) and function in a CRM1-dependent manner, possibly as a consequence of demasking a nuclear export signal (amino acid position 64-80). S-nitrosylation at Cys-93 and Cys-310 regulates its nuclear-cytosolic shuttling. Ubiquitinated form is localized predominantly in the cytoplasm. {ECO:0000250}.
Top Pathways Base excision repair