ALKBH3, a homolog of E.coli AlkB (Trewick et al. 2002), removes the methyl group from 3-methylcytosine (3-meC) in a reaction dependent on alpha-ketoglutarate, oxygen and Fe2+. ALKBH3 directly reverses the alkylating damage of DNA in the form of 3-meC, releasing formaldehyde (Duncan et al. 2002). The reversal of alkylating damage of dsDNA by ALKBH3 requires the presence of DNA helicase ASCC3, a component of the activating signal co-integrator complex (Dango et al. 2011). ALKBH3 can also repair methylated RNA (Aas et al. 2003).