Transcription regulator that acts as a key regulator of lineage commitment of immature T-cell precursors. Exerts distinct biological functions in the mammary epithelial cells and T cells in a tissue-specific manner. Necessary and sufficient for commitment of CD4 lineage, while its absence causes CD8 commitment. Development of immature T-cell precursors (thymocytes) to either the CD4 helper or CD8 killer T-cell lineages correlates precisely with their T-cell receptor specificity for major histocompatibility complex class II or class I molecules, respectively. Cross-antagonism between ZBTB7B and CBF complexes are determinative to CD4 versus CD8 cell fate decision. Suppresses RUNX3 expression and imposes CD4+ lineage fate by inducing the SOCS suppressors of cytokine signaling. induces, as a transcriptional activator, SOCS genes expression which represses RUNX3 expression and promotes the CD4+ lineage fate. During CD4 lineage commitment, associates with multiple sites at the CD8 locus, acting as a negative regulator of the CD8 promoter and enhancers by epigenetic silencing through the recruitment of class II histone deacetylases, such as HDAC4 and HDAC5, to these loci. Regulates the development of IL17-producing CD1d-restricted naural killer (NK) T cells. Also functions as an important metabolic regulator in the lactating mammary glands. Critical feed-forward regulator of insulin signaling in mammary gland lactation, directly regulates expression of insulin receptor substrate-1 (IRS-1) and insulin-induced Akt-mTOR-SREBP signaling (By similarity). Transcriptional repressor of the collagen COL1A1 and COL1A2 genes. May also function as a repressor of fibronectin and possibly other extracellular matrix genes (PubMed:9370309). Potent driver of brown fat development, thermogenesis and cold-induced beige fat formation. Recruits the brown fat lncRNA 1 (Blnc1):HNRNPU ribonucleoprotein complex to activate thermogenic gene expression in brown and beige adipocytes (By similarity). Homodimerizes. Interacts with NCL, NEDD4 and YBX1. Interacts with HNRNPU (via RNA-binding RGG-box region); the interaction facilitates the recruitment of long non-coding RNA Blnc1 by ZBTB7B. Interacts with HDAC4 and HDAC5; the interaction allows the recruitment of HDAC4 and HDAC5 on CD8 loci for deacetylation and possible inhibition of CD8 genes expression. Acetylated directly and specifically by EP300 (PubMed:20810990). EP300-mediated acetylation of Lys-206, Lys-212 and Lys-335 stabilizes the protein by antagonizing ubiquitin conjugation (By similarity). Ubiquitinated, leading to proteasomal degradation (PubMed:20810990). Competes with acetylation on Lys-206, Lys-212 and Lys-335 (By similarity).