third malignant brain tumor (MBT) repeat found in Drosophila melanogaster Polycomb protein Sfmbt (dSfmbt) and similar proteins
dSfmbt, also called Scm-like with four MBT domain-containing protein 1, is a Polycomb group repressor involved in epigenetic regulation of gene expression. dSfmbt contains 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 third MBT repeat that does not seem to contain a semi-aromatic cage and may not bind methylated lysine residues.
Jiyao W et al.(2023). "The conserved domain database in 2023.",