Digitonin-high salt extracts prepared from cells 72 hr after siRNA transfection were processed for immunoblots using antisera for STT3A, STT3B, ribophorin I (R I), BiP, Sec61α, and the α-subunit of the F1F0-ATPase. Asterisks designate nonspecific bands. Similar results were obtained using a second set of each of the siRNAs. The negative control siRNA is abbreviated NC.