shRNA knockdown of the transcription factor NFYA in H322 and HCT116

The trimeric transcription factor -TF- NF-Y binds to the CCAAT box, an element enriched in promoters of genes overexpressed in tumors. The NF-YC subunit was recently identified as an oncogene in choroid plexus carcinomas. Previous studies on the NF-Y regulome identified the general term metabolism as significantly enriched. We dissect here in detail the targeting of metabolic genes by integrating analysis of NF-Y genomic binding and profilings after inactivation of NF-Y subunits in different cell types. NF-Y comprehensively controls de novo biosynthetic pathways of lipids, teaming up with the master SREBPs regulators. It activates glycolytic genes, but, surprisingly, is neutral, or represses mitochondrial respiratory genes. NF-Y targets the SOCG (Serine, One Carbon, Glycine) and Glutamine pathways, as well as genes involved in the biosynthesis of polyamines and purines. Within the different pathways, cancer-driving nodes are under NF-Y positive control. Altogether, these data delineate a coherent strategy to promote expression of metabolic genes fuelling anaerobic energy production, and other anabolic pathways commonly altered in cancer cells. Scrambled control (shSCM) and NF-YA pLKO.1-shRNAs were designed by Sigma-Aldrich. The puromycin resistance cassette was replaced with an EGFP cassette. Viral production and transduction were carried out as previously described (Benatti et al. 2011). H322 and HCT116 were transduced with shSC or shNF-YA viral supernatants, in triplicates and cells collected after 72 hours. RNA was prepared according to Affymetrix standard protocol and hybridized to Hu-Gene 2.0 expression arrays.

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