Fig 4. Absence of HIF1α impairs gammaherpesvirus lytic replication in low oxygen concentration.

(A) HIF1α expression during MHV68 time-course infection at 3% O₂ (4,8,12 and 24 hpi) was measured by western blot. (B) HIF1α WT and HIF1α Null MEFs were infected with MHV68 (B: MOI 5.0) in a single-step and (C: MOI 0.5) in a multi-step infection and transferred to 3% oxygen. Released virus in the supernatant was measured by plaque assay. Graph represents one of at least three independently performed experiments with similar results. Statistical significance was determined in Graph Pad Prism by Student’s t- test with n = 3. **, P< 0.01; ***, P< 0.005. (D) Selected viral genes with statistical significance p<0.05 of HIF1α Null 3% O₂ normalized to HIF1α Null 21% O₂.