After activation, ATG12 is transferred to ATG10, which has a function that is analogous to an E2 enzyme (Shintani et al. 1999, Mizushima et al. 2002). ATG12 is transferred to the Cys-166 residue of ATG10 to form a thioester (Nemoto et al. 2003).
Atg12 transferase activity of ATG12:ATG7:CysO572-ATG7:ATG10 [cytosol]