Fig. 4

ATAD3A regulates mitochondrial ERK1/2 activation in HNSCC cells. A, B The effect of ATAD3A KO on the activation of phospho-kinases in HN12 cells determined by Human Phospho-Kinase array. Representative images and quantitative data (n = 2) are respectively shown in (A) and (B). C The effect of ATAD3A KO on ERK1/2 inactivation validated in HN12 cells by Western blotting. D The effect of ATAD3A KO on ERK1/2 inactivation in HN8 and HN17 cells. E The phosphorylation levels of ERK1/2 in tumor xenografts from mice implanted with ATAD3A KO or parental HN12 cells determined by IHC. Representative images and quantitative data are shown in the left and right panels, respectively. F The effect of ATAD3A overexpression on ERK1/2 activation. G The effect of ATAD3A WA dead mutant on ERK1/2 activation. H The effect of ATAD3A KO on the cytosolic and mitochondrial ERK1/2 activation in HN12 cells. The purity of the mitochondrial fractions was indicated by the mitochondrial COXIV protein and the absence of cytosolic GAPDH protein, nuclear PCNA protein and ER-localized Calnexin protein. I, J Volcano (I) and butterfly (J) plots resulted from the differential expression analysis between ATAD3A KO and parental HN12 cells. K GO enrichment analysis of DEGs resulting from ATAD3A loss showing downregulation of the ERK1/2 related pathways upon ATAD3A KO in HN12 cells. L A down-regulated enrichment plot for a priori gene sets for the regulation of MAPK activity. M The effect of SCH772984 on TNFα expression in three HNSCC cell lines determined by RT-qPCR. N The effect of ATAD3A loss on TNFα expression in three HNSCC cell lines determined by RT-qPCR. O The effect of ATAD3A overexpression on TNFα expression in three HNSCC cell lines determined by RT-qPCR. Cyto: cytosol; Mito: mitochondria. *p < 0.05; **p < 0.01