Binds DNA and acts as a transcriptional repressor (PubMed:10488076). Involved in the regulation of systematic glucose homeostasis and insulin sensitivity, via transcriptional repression of downstream insulin signaling targets such as OBP2A/LCN13 (By similarity). Acts as a negative regulator of lipogenic gene expression in hepatocytes and thereby mediates the control of very low-density lipoprotein release (PubMed:23307490). May play a role in neurite elongation and survival (By similarity). {ECO:0000250|UniProtKB:Q9EQN3, ECO:0000269|PubMed:10488076, ECO:0000269|PubMed:23307490}. This is the function of TSC22D4 (TSC22 domain family member 4, ENSG00000166925).