fourth malignant brain tumor (MBT) repeat found in the Scm-like with four MBT domains protein (SFMBT) family
The SFMBT family includes SFMBT1 and SFMBT2. SFMBT1, also called renal ubiquitous protein 1, is a transcriptional repressor protein that selectively binds the N-terminal tail of histone H3 and functions as a chromatin reader in regulating epigenetic silencing and the myogenic gene program. It mediates the recruitment of corepressor complexes to target genes, followed by chromatin compaction and repression of transcription. SFMBT2, also called Scm-like with 4 MBT domains protein 2, is a transcriptional repressor of the HOXB13 gene. It is required for trophoblast maintenance and placenta development. It also negatively regulates cell migration and invasion in prostate cancer cells. Members of this family contain four MBT (malignant brain tumor) repeats. The MBT repeat is a protein module that recognizes methylated lysine residues on histones. MBT repeats contain a semi-aromatic cage to accommodate methyllysine and show specificity towards the lower methylation states of lysine. This model corresponds to the fourth MBT repeat that does not contain a semi-aromatic cage and may not bind methylated lysine residues.
Jiyao W et al.(2023). "The conserved domain database in 2023.",