FIG. 4.

Characterization of translation initiation factors during CrPV infection. (A) Immunoblots of d4E-BP, deIF4A, dPABP, deIF4G, and deIF4E from equal amounts of lysates (shown in Fig. 1B) of mock (M)- and CrPV-infected S2 cells at the indicated time postinfection. (B) Equal amounts of lysates from mock (M)-, UV-irradiated (UV)-, and CrPV-infected S2 cells (5 FFU) at each time point were subjected to m⁷G-Sepharose bead pulldowns. “1 M” and “6 M” denote mock infections at 1 and 6 h, respectively. Proteins retained in the cap resin were resolved by SDS-PAGE analysis and immunoblotted with antisera against deIF4G, deIF4E, and d4E-BP. (C) Immunoblots of phospho-eIF2α (P-deIF2α) and deIF2α from equal amounts of lysates (shown in Fig. 1B) of mock (M)- and CrPV-infected S2 cells at the indicated times postinfection (below). Quantitation of the fraction of P-deIF2α in CrPV-infected S2 cells compared to that in mock-infected cells (given as 1.0) was carried out. (D) Immunoblots of phospho-eIF2α (P-deIF2α) and total deIF2α from lysates of CrPV and UV-irradiated infected cells.