third malignant brain tumor (MBT) repeat found in Lethal(3)malignant brain tumor-like protein 2 (L3MBTL2)
L3MBTL2, also called L(3)mbt-like protein 2, is a putative Polycomb group (PcG) protein that binds to monomethylated and dimethylated 'Lys-20' on histone H4 and also binds histone H3 peptides which are monomethylated or dimethylated on 'Lys-4', 'Lys-9' or 'Lys-27'. L3MBTL2 orchestrates ubiquitin signalling by dictating the sequential recruitment of RNF8 and RNF168 after DNA damage. It is an integral component of the polycomb repressive complex 1.6 (PRC1.6) and has been implicated in transcriptional repression and chromatin compaction. L3MBTL2 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.
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