Fig. 2: SARS-CoV-2 ORF3a blocked autophagy and caused the accumulation of autophagosomes.
From: The SARS-CoV-2 protein ORF3a inhibits fusion of autophagosomes with lysosomes
a ORF3a inhibited autophagy in a dose-dependent manner. Increasing amounts of SARS-CoV-2 ORF3a-expressing plasmids were transfected into HeLa cells, and the effect on autophagy was analyzed by detecting the protein levels of p62 and LC3-II. b ORF3a inhibited autophagy under autophagy-inducing conditions. ORF3a was expressed in HeLa or A549 cells with or without EBSS or INK128 treatment. The protein levels of p62 and LC3-II were then analyzed. c ORF3a cannot further inhibit autophagy under autophagy-blocking conditions. ORF3a was expressed in HeLa or A549 cells with or without subsequent treatment with CQ (chloroquine). The protein levels of p62 and LC3-II were then analyzed. d ORF3a cannot further inhibit autophagy in autophagy-blocked HeLa cells with the ATG7 gene knocked out. e ORF3 expression caused the accumulation of autophagosomes. ORF3a was expressed in HeLa cells with stable expression of GFP-LC3. Puncta of GFP-LC3 (representing autophagosomes) were observed and counted. Scale bars, 0.5 μm.
