Carbohydrate response element binding protein (ChREBP) is a key transcriptional regulator of de novo lipogenesis (DNL) in response to carbohydrates and in hepatic steatosis. Mechanisms underlying nutrient modulation of ChREBP are under active investigation. Here we identify host cell factor 1 (HCF-1) as a previously unknown ChREBP-interacting protein that is enriched in liver biopsies of nonalcoholic steatohepatitis (NASH) patients. Biochemical and genetic studies show that HCF-1 is O-GlcNAcylated in response to glucose as a prerequisite for its binding to ChREBP and subsequent recruitment of OGT, ChREBP O-GlcNAcylation, and activation. The HCF-1:ChREBP complex resides at lipogenic gene promoters, where HCF-1 regulates H3K4 trimethylation to prime recruitment of the Jumonji C domain-containing histone demethylase PHF2 for epigenetic activation of these promoters. Overall, these findings define HCF-1's interaction with ChREBP as a previously unappreciated mechanism whereby glucose signals are both relayed to ChREBP and transmitted for epigenetic regulation of lipogenic genes. • HCF-1 binds ChREBP and is required for glucose stimulation of de novo lipogenesis • HCF-1 recruits OGT to ChREBP, stimulating ChREBP O-GlcNAcylation and activation • Nutrient induction of HCF-1 O-GlcNAcylation is required for its binding to ChREBP • HCF-1 recruits epigenetic activators to promoters of lipogenic genes Lane et al. identify HCF-1 as a ChREBP-modulatory protein relevant for de novo lipogenesis. Glucose stimulation triggers HCF-1 O-GlcNAcylation, priming its association with ChREBP and OGT recruitment for ChREBP O-GlcNAcylation and increased ChREBP transcriptional activity. The HCF-1:ChREBP complex imparts glucose-dependent epigenetic regulation to lipogenic promoters by recruiting epigenetic modifiers. [ABSTRACT FROM AUTHOR]