Fig. 4: TRIM8 interacts with HNF1α and inhibits the transcriptional activity of HNF1α.

A Mass spectrometry analysis revealed the potential interaction between HNF1α and TRIM8. B, C Co-IP assays were performed to detect the interaction between exogenous HNF1α and TRIM8 in HEK293T cells transfected with the plasmids expressing V5-HNF1α and Flag-TRIM8. D In situ proximity ligation assay was performed to detect the interaction between HNF1α and TRIM8 in Huh7 cells. Scale bars = 50 μm. E GSEA analysis of our acquired RNA sequencing data showed an enrichment of HNF1α target genes in the TRIM8-KO groups. Gene correlation analysis between TRIM8 and HNF1α target genes including ALDOB (F), APOC3 (G) and TTR (H) based on TCGA-LIHC database. Luciferase reporter assays were performed to evaluate the activity of the HNF1α promoter in Huh7 cells transfected with the plasmid overexpressing TRIM8 (I) or siTRIM8 (J). Relative mRNA levels of HNF1α target genes in MHCC-L cells infected with control lentivirus or lenti-TRIM8 (K) and MHCC-L cells transfected with control siRNA or siTRIM8 (L). M IPA analysis showed the ingenuity canonical pathways of DEGs which were upregulated both in HNF1α-overexpressing cells and in TRIM8-knockout cells. N IPA analysis showed the diseases and bio functions of DEGs which were upregulated both in HNF1α-overexpressing cells and in TRIM8-knockout cells. I–L Experiments were performed in triplicate and data are presented as means ± SEM. *P < 0.05, **P < 0.01 and ***P < 0.001 using two- tailed Student’s t tests.