Figure 5.

Knockdown of endogenous IFITM1 and IFITM3 significantly promotes ATMUV replication in DF-1 cells. DF-1 cell lines stably expressing specific shRNAs targeting chicken IFITM1, 2, 3 or luciferase control were infected with or without ATMUV at a MOI of 1.0 and harvested at indicated time points of 24, 36, and 48 hpi. (A–C) qRT-PCR was performed to measure interference efficiency of the shRNAs. (D) Viral load in cell culture supernatants was titrated via TCID₅₀ assay in DEF cells. (E) DF-1 cell lines expressing specific IFITM-shRNA were infected with ATMUV and harvested at 36 hpi, followed by qRT-PCR assay to detect mRNA expression of viral genes. The mRNA levels were normalized to the endogenous β-actin level and the expression in ATMUV infected DF-1 cell line expressing luc-shRNA control was set to 1.0. mRNA expression in DF-1 cells expressing specific IFITM-shRNA was compared to that in control cells expressing luc-shRNA. Plotted are the average results from three independent experiments (means ± SD). Statistical significance was determined by one tail Student's t-test analysis. ^*P < 0.05, ^**P < 0.01.