SAFB
Function
Binds to scaffold/matrix attachment region (S/MAR) DNA and forms a molecular assembly point to allow the formation of a 'transcriptosomal' complex (consisting of SR proteins and RNA polymerase II) coupling transcription and RNA processing (PubMed:9671816). Functions as an estrogen receptor corepressor and can also bind to the HSP27 promoter and decrease its transcription (PubMed:12660241). Thereby acts as a negative regulator of cell proliferation (PubMed:12660241). When associated with RBMX, binds to and stimulates transcription from the SREBF1 promoter (By similarity).
Post-translational modifications
Sumoylated by PIAS1 with SUMO1 and SUMO2/3, desumoylated by SENP1. Sumoylation is required for transcriptional repressor activity.
Tissue Specificity
Ubiquitous. Expressed at high levels in the CNS and at low levels in the liver. Expressed in a wide number of breast cancer cell lines.
Cellular localization
- Nucleus
Alternative names
HAP, HET, SAFB1, SAFB, Scaffold attachment factor B1, SAF-B, SAF-B1, HSP27 estrogen response element-TATA box-binding protein, HSP27 ERE-TATA-binding protein