Aprataxin Antibody (YA2138)

Aprataxin (APTX) is a member of the histidine triad (HIT) superfamily and functions as a DNA repair factor that protects cells from genotoxic stress by maintaining the integrity of damaged DNA termini during repair processes^[1][2]. Mechanistically, aprataxin resolves abortive DNA ligation intermediates by removing adenylate (AMP) groups covalently linked to 5′-phosphate DNA ends, thereby restoring ligatable DNA substrates and enabling completion of strand break repair^[2]. Through interactions with DNA repair proteins including XRCC1 and XRCC4, aprataxin participates in pathways associated with single-strand break repair, double-strand break repair, and base excision repair, linking DNA end processing to genome maintenance^[1][3][4]. Defects in APTX cause ataxia with oculomotor apraxia type 1 (AOA1), a neurodegenerative disorder in which unrepaired DNA strand breaks are thought to accumulate progressively as a consequence of failed DNA ligation events^[2]. Experimental studies further demonstrate that APTX-deficient cells exhibit increased sensitivity to DNA damage and altered cellular responses to genotoxic stress, supporting a direct role for aprataxin in preserving genomic stability^[1][2]. Compared with other HIT family proteins, aprataxin possesses a unique DNA deadenylation activity that specifically hydrolyzes DNA-adenylate repair intermediates, distinguishing its biological function from related nucleotide hydrolases^[2]. This specialized enzymatic activity makes aprataxin a valuable model for investigating DNA ligation fidelity, DNA damage responses, and mechanisms underlying neurodegeneration associated with defective DNA repair^[1][2].