FIG. 3.

Effects of US3 on class I and class II synthesis and maturation. His16 cells were left uninfected (UN; A to C) or were infected with AdtetUS3 and Adtet-trans at 100 and 20 or 200 and 40 (A and C) or 150 and 30 PFU/cell (B), respectively, for 18 h. Infected cells were labeled with [³⁵S]methionine-cysteine in a pulse-chase format. DR-α and DR-β (A), Ii (B), and MHC-I HC (C) were immunoprecipitated from cell extracts with MAb DA6.147, HB10A, and PIN.1, and rabbit anti-HC serum, respectively. (D) His16 cells were infected with Adtet-trans alone at 120 PFU/cell, AdtetUS2 and Adtet-trans at 100 and 20 PFU/cell, respectively, or AdtetUS3 and Adtet-trans at 100 and 20 PFU/cell, respectively. The cells were labeled for 12 min, the label was chased for 120 min, and then DM-α and DM-β were immunoprecipitated with MAbs 5C1 and MaP.DMB/C, respectively. For endo H treatment, precipitated proteins were divided in half and treated with endo H (+) or not treated (−). The proteins were subjected to SDS-polyacrylamide gel electrophoresis and visualized by autoradiography. r, endo H-resistant species of DM; s, endo H-susceptible species of DM.