Translation decreases the co-IP of the UPF3X and eIF4AIII EJC constituents with IRE-Gl mRNA but does not affect the co-IP of CBP80 or eIF4E with IRE-Gl mRNA. (A) Lysates from hemin-treated or Df-treated HeLa cells that stably express IRE-Gl Norm mRNA, referred to here as IRE-Gl mRNA, were immunoprecipitated using the specified antibody (α) or, as a control for nonspecific IP, NRS. (B) RT–sqPCR analysis of IRE-Gl mRNA and SMG7 mRNA before or after the IP shown in A, where the normalized level of IRE-Gl mRNA in the presence of hemin is defined as 100. (C) Western blotting before and after IP using NRS, anti-CBP80, or anti-eIF4E. (D) As in B, except the samples from the IP shown in C were used. Results are representative of three independently performed experiments.