Required for the switching of fetal globin species, and beta- and gamma-globin genes regulation during erythroid differentiation. Plays a role in chromatin organization and nuclear architecture during apoptosis (By similarity). Crucial silencing factor contributing to the initiation of X inactivation mediated by Xist RNA that occurs during embryogenesis and in lymphoma. Binds to DNA at special AT-rich sequences, the consensus SATB1-binding sequence (CSBS), at nuclear matrix- or scaffold-associated regions. Thought to recognize the sugar-phosphate structure of double-stranded DNA. Transcriptional repressor controlling nuclear and viral gene expression in a phosphorylated and acetylated status-dependent manner, by binding to matrix attachment regions (MARs) of DNA and inducing a local chromatin-loop remodeling. Acts as a docking site for several chromatin remodeling enzymes and also by recruiting corepressors (HDACs) or coactivators (HATs) directly to promoters and enhancers. Modulates genes that are essential in the maturation of the immune T-cell CD8SP from thymocytes. Promotes neuronal differentiation of neural stem/progenitor cells in the adult subventricular zone, possibly by positively regulating the expression of NEUROD1 (PubMed:26305964). Interacts with PCAF. Interacts with sumoylated PML and HDAC1 Tat via the ULD domain. Interacts also with DYNLT3 and POLR2J2. Binds to EP300 (By similarity). Homodimer. Part of the nuclear protein complex gamma-globin promoter and enhancer binding factor (gamma-PE) composed at least of SATB1 and HOXB2. Interaction with CtBP1 when not acetylated stabalizes attachment to DNA and promotes transcription repression. Interacts with CUX1 (via DNA-binding domains); the interaction inhibits the attachment of both proteins to DNA. Organized into a cage-like network anchoring loops of heterochromatin and tethering specialized DNA sequences. When sumoylated, localized in promyelocytic leukemia nuclear bodies (PML NBs) (By similarity). Expressed in the subventricular zone, rostral migratory stream and in the olfactory bulb (at protein level) (PubMed:26305964). Mainly expressed in thymus, spleen, and lymph nodes with a lower level observed in the brain (PubMed:15814699). Up-regulated during adult neuronal stem cell differentiation. Sumoylated. Sumoylation promotes cleavage by caspases. Phosphorylated by PKC. Acetylated by PCAF. Phosphorylated form interacts with HDAC1, but unphosphorylated form interacts with PCAF. DNA binding properties are activated by phosphorylation and inactivated by acetylation. In opposition, gene expression is down-regulated by phosphorylation but up-regulated by acetylation (By similarity). Cleaved at Asp-254 by caspase-3 and caspase-6 during T-cell apoptosis in thymus and during B-cell stimulation. The cleaved forms cannot dimerize and lose transcription regulation function because of impaired DNA and chromatin association. Mice are small in size, have disproportionately small thymi and spleens, and die at 3 weeks of age. Multiple defects in T-cell development are observed, including interrupted thymocytes differentiation and abnormal T-cell transcriptome. RNAi-mediated knockdown in neural stem/progenitor cells in the adult subventricular zone impairs early neuronal differentiation (PubMed:26305964). Belongs to the CUT homeobox family.