Figure 4.

IFN-γ–induced specific degradation of MyHC is not attributable to the lysosome-autophagosome pathway. A: Quantification of proteolytic activity after inhibition of lysosome in NRVMs treated with vehicle (control) or lysosome inhibitor (NH₄Cl), normalized to vehicle-treated NRVMs. B: Left panel: Representative myofibrillar gel of protein lysates from NRVMs treated with lysosome inhibitor (NH₄Cl) and vehicle or IFN-γ. MyHC band is as indicated. Right panel: Densitometric quantification of MyHC band intensities, normalized to vehicle-treated cells. C: Representative Western blot using antibodies raised against light chain 3 (LC3)-II, a marker of autophagosome activity, or glyceraldehyde-3-phosphate dehydrogenase (GAPDH) on lysates from NRVMs treated with vehicle, IFN-γ, IFN-γ plus an autophagosome inhibitor [3-methyladenine (3-MA)], or rapamycin (Rap). D: Left panel: Representative myofibrillar gel of protein lysates from NRVMs treated with 3-MA and vehicle or IFN-γ. MyHC band is as indicated. Right panel: Densitometric quantification of MyHC band intensities normalized to vehicle-treated cells. ***P < 0.001 compared with control.