Quantitative Proteomics Identify a Novel DNA Repair-Dependent Role for Hepatocyte Nuclear Factor 4α

ABSTRACT: Hepatocyte nuclear factor 4 (HNF4) is a transcription factor that acts as a master regulator of genes in several endodermal-derived tissues, including the intestine in which it plays a central role during development and tumorigenesis. To better delineate the mechanisms by which HNF4 can interfere during these processes, we combined stable isotope labelling with amino acids in cell culture (SILAC)-based quantitative proteomics with immunoprecipitation of green fluorescent protein (GFP) as well as with proximity-dependent purification by the biotin ligase BirA, both fused to HNF4. Surprisingly, these analyses identified a significant enrichment of proteins falling into the DNA repair gene ontology term, a so far unidentified biological feature of this transcription factor. Several of these proteins including PARP1, RAD50 and DNA-PKcs were confirmed to interact with HNF4in colorectal cancer cell lines. During DNA damage response, HNF4 localized to double strand DNA breaks in these cells. HNF4was able to interfere functionally during non-homologous end-joining (NHEJ). Overall, these observations identify an unsuspected role for this transcription factor during the DNA damage response.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Epithelial Cell, Colon

DISEASE(S): Colon Cancer

SUBMITTER: Samuel Wilson  

LAB HEAD: François Boudreau

PROVIDER: PXD008365 | Pride | 2019-11-12

REPOSITORIES: Pride