Some ferritin L is N-glycosylated. (A) HepG2 cells infected with AdX-FL were labeled with 35S-methionine. The media was immunoprecipitated with polyclonal antibodies against ferritins and the washed beads were divided into 2 aliquots. One aliquot was treated with endoH (+) while the other aliquot was left untreated (-). EndoH does not affect the mobility of the proteins. (B) Radiolabeled ferritins were immunoprecipitated from the media of AdX-FL–infected HepG2 cells. The washed immunoprecipitates were boiled in 1% SDS and the supernatant was diluted in reaction buffer and divided into 2 aliquots. One aliquot was treated with PNGaseF for one hour while the other aliquot was left untreated. After treatment with PNGaseF, the proteins of higher molecular mass in the medium (#) decreased in intensity, whereas the intensity of bands corresponding to ferritin L and modified ferritin L (*) increased.
