Fig. 7

Proteomics research showed that nuclear TKT interacts with transcription factors, including EGFR, and may regulate the stress response and cell activation processes. a Heat maps of the identified proteins in the 3 stable cell lines. Left: total identified proteins; Upper right: identified kinases, Bottom right: identified transcription factors and co-regulators (TFs/TCs). b GO annotation analysis of the 243 TKT-WT unique proteins (TKT/Vector > 5 Folds and TKT/K6R >5 Folds). Blue bar: -Log of the p value. c Protein network analysis of TKT-WT unique proteins. The cell stress response-related kinases, TCs and TFs (red edges) were identified only in the TKT-WT group. Some nuclear transport proteins were also found interacted with TKT-WT (blue edges). d Cross-linking Co-IP and western blot assay taking TKT as the bait protein. The vector control, TKT-WT and TKT-K6R overexpressing Huh7 cells were cross-linked and nuclei were extracted and lysed by sonication. TKT antibody was used for Co-IP. Flag (for exogenous TKT detection), EGFR, MAPK3, IPO4 and NUP54 antibodies were used for western blot assay. e Cross-linking Co-IP and western blot assay taking TKT as the prey protein. The TKT-WT overexpressing Huh7 cells were cross-linked and nuclei were extracted and lysed by sonication. EGFR/MAPK3 and IgG antibodies were used for Co-IP. Flag (for exogenous TKT detection), TKT antibody was used for western blot assay. f Viability of vector control, TKT-D155A and TKT-D155A-K6R overexpressing cell lines with or without the EGF or erlotinib treatment in Huh7 cells under oxidative stress induced by H₂O₂ (treated for 6 h). g The proliferation assay of vector control, TKT-D155A and TKT-D155A-K6R overexpressing cell lines with or without the EGF or erlotinib treatment in Huh7 cells