Dioxygenase that mediates demethylation of DNA and RNA containing 1-methyladenosine (m1A) (  ). Repairs alkylated DNA containing 1-methyladenosine (m1A) and 3-methylcytosine (m3C) by oxidative demethylation ( , ). Has a strong preference for single-stranded DNA ( , ). Able to process alkylated m3C within double-stranded regions via its interaction with ASCC3, which promotes DNA unwinding to generate single-stranded substrate needed for ALKBH3 . Can repair exocyclic 3,N4-ethenocytosine adducs in single-stranded DNA . Also acts on RNA (  ). Demethylates N(1)-methyladenosine (m1A) RNA, an epigenetic internal modification of messenger RNAs (mRNAs) highly enriched within 5'-untranslated regions (UTRs) and in the vicinity of start codons (, ). Requires molecular oxygen, alpha-ketoglutarate and iron (, ).
Subcellular locations: Nucleus, Cytoplasm
Colocalizes with ASCC2 and ASCC3 in nuclear foci when cells have been exposed to alkylating agents that cause DNA damage . Predominantly localizes to the nucleus.
Ubiquitous. Detected in heart, pancreas, skeletal muscle, thymus, testis, ovary, spleen, prostate, small intestine, peripheral blood leukocytes, urinary bladder and colon.