Mitochondrial morphodynamics are modulated by physiological range of temperature and influence host cell outcomes during influenza infection

Abstract Influenza viruses replicate in both the cooler, upper portions of the airway and the warmer, lower portions of the respiratory tract. This study investigates how physiological ranges of temperature, specifically 33°C and 37°C, impact host cell biology and how temperature-dependent differences in host cells influence outcomes during influenza A virus infection. This study prioritizes describing mitochondrial networks due to their importance in maintaining cellular homeostasis and mediating immune responses to viral infection. The temperature at which cells are incubated significantly influences mitochondrial network morphology and mitochondrial function. Moreover, temperature-dependent changes to mitochondrial networks prior to infection result in temperature-specific changes to host cell outcomes during infection. These findings indicate that mitochondrial structure alone can modulate host cell outcomes during viral infection and that both the form and function of mitochondria directly impact influenza A virus production. While not all mitochondrial processes were shown to be affected by temperature or infection, these results highlight the importance of using physiologically relevant temperatures in respiratory pathogen research and elucidate how mitochondrial dynamics contribute to host cell outcomes during influenza A virus infection. Importance Respiratory viruses infect the upper and lower respiratory tract but rarely is the impact of physiological ranges of temperature (33°C to 37°C) considered. Mitochondria are central mediators of numerous physiological pathways, and their functions are often modified by virus infection. Physiological ranges of temperature can alter mitochondrial form and function, which is further impacted by virus infection. The study sheds light on how temperature can impact mitochondrial form and function in concert with virus infection.