ADP-ribosylated BiP is enriched in low–molecular weight fractions of the ER extract. (A) Coomassie-stained SDS-PAGE of pancreatic microsomal proteins from fasted and fed mice resolved by gel filtration. BiP is distributed bimodally between a high–molecular weight peak containing the cochaperone ORP150 and GRP94 and lower–molecular weight peak. A representative experiment reproduced three times is shown. Abs., absorbance; mAU, milli–absorbance unit. (B) BiP immunoblot of IEF gels of the input (GF input) and fractions 9 and 14 of the fasted and 1-h refed samples above. The ratio of ADP ribosylated to total BiP in each lane is indicated (R). Black lines indicate that intervening lanes have been spliced out.
ADP-ribosylated BiP is enriched in low–molecular weight fractions of the ER extract. (A) Coomassie-stained SDS-PAGE of pancreatic microsomal proteins from fasted and fed mice resolved by gel filtration. BiP is distributed bimodally between a high–molecular weight peak containing the cochaperone ORP150 and GRP94 and lower–molecular weight peak. A representative experiment reproduced three times is shown. Abs., absorbance; mAU, milli–absorbance unit. (B) BiP immunoblot of IEF gels of the input (GF input) and fractions 9 and 14 of the fasted and 1-h refed samples above. The ratio of ADP ribosylated to total BiP in each lane is indicated (R). Black lines indicate that intervening lanes have been spliced out.
