(A) Different cell types were lysed and analysed by SDS/PAGE and Western blotting. The membrane was incubated with a rabbit hARD1-peptide-specific polyclonal antibody. *, A slowly migrating hARD1 variant, a hARD1 containing complex or probably an unspecific band. Lanes: 1, ARO; 2, HEK-293; 3, HeLa; and 4, NB4. (B) As in (A) using an NATH-specific polyclonal antibody. The experiment was repeated more than three times.