Figure 5. Genetic knockdown of mTOR kinase blocks viral protein synthesis. Lenti-viral short-hairpin RNAs (shRNA) were used to knockdown expression of mTOR in A549 cells. shmTOR-A549 cells were infected with RSV NH409A. Cellular and viral protein expression was measures at 24 h post infection (m.o.i = 0.2). Asterisk ( * ) or non-significant (ns) is compared to Scramble/RSV control. ( A ) Western blot analysis of cellular and protein expression. ( B – I ) Quantification of protein synthesis displayed in panel A (n = 3). ( B ) mTOR/β-actin; ( C ) Rictor/β-actin; ( D ) Raptor/β-actin; ( E ) phospho-Akt/Akt; ( F ) phospho-S6K1/S6K1; ( G ) total ribosomal protein S6/β-actin; ( H ) RSV nucleoprotein N/β-actin; ( I ) RSV fusion protein F1/β-actin. Error bars, SEM; *, p < 0.05; **, p < 0.01; ***, p < 0.001; ****, p < 0.0001; n.s.