MBD5 and MBD6 interact with the human PR‐DUB complex through their methyl‐CpG‐binding domain

Abstract

MBD5 and MBD6 are two members of the methyl-CpG-binding domain (MBD) family of proteins that are poorly characterized. Studies performed thus far have failed to show binding of the MBD5 and MBD6 MBD to methylated DNA. Here, we show that both MBD5 and MBD6 interact with the mammalian PR-DUB Polycomb protein complex in a mutually exclusive manner. Strikingly, the MBD of MBD5 and MBD6 is both necessary and sufficient to mediate this interaction. Chromatin immunoprecipitation analyses reveal that MBD6 and FOXK2/PR-DUB share a subset of genomic target genes, suggesting a functional interaction in vivo. Finally, we show that MBD6, but not MBD5, is recruited to sites of DNA damage in a PR-DUB independent manner. Our study thus implies a shared function for MBD5 and MBD6 through an interaction with PR-DUB, as well as an MBD6-specific recruitment to sites of DNA damage.

Layers of DUB regulation

“…Another example of multiple layers of regulation impinging on a single protein is the tumor suppressor BAP1. This enzyme is activated by ASXL1 to deubiquitylate H2A and can be targeted to certain genomic loci by its association with transcriptional regulators [20,61,92]. BAP1 can furthermore be spatially separated from its targets by ubiquitylation of its C-terminal nuclear localization signal (NLS) by UBE2O, causing mislocalization to the cytoplasm [84].…”

FOXK2 suppresses the malignant phenotype and induces apoptosis through inhibition of EGFR in clear‐cell renal cell carcinoma

“…10 Previous studies have shown that FOXK2 was involved in many molecular mechanisms, including starvationinduced autophagy, 11 cell adhesion and motility, 12,13 chromatin structure modification, [12][13][14] G/T-mismatch repair 15 and cell cycle regulation. 10 Previous studies have shown that FOXK2 was involved in many molecular mechanisms, including starvationinduced autophagy, 11 cell adhesion and motility, 12,13 chromatin structure modification, [12][13][14] G/T-mismatch repair 15 and cell cycle regulation.…”

“…Forkhead box K2 (FOXK2) is a forkhead box transcription factor, which was initially recognized as a regulator of IL-2 transcription. 10 Previous studies have shown that FOXK2 was involved in many molecular mechanisms, including starvationinduced autophagy, 11 cell adhesion and motility, 12,13 chromatin structure modification, [12][13][14] G/T-mismatch repair 15 and cell cycle regulation. 16 FOXK2 was also reported to play important roles in the carcinogenesis of breast cancer [17][18][19] and colorectal cancer.…”

Live‐Cell Imaging of DNA Methylation Based on Synthetic‐Molecule/Protein Hybrid Probe

“…On the other hand, the MBD‐based approach offers real‐time images of the precise localization of methylated DNA in living cells. Mammalian MBD protein family consist of 11 proteins that are characterized by a methyl‐CpG‐binding domain containing 70–80 amino acids . The dissociation constants of MBD proteins toward methylated DNA were reported to be in the micromolar to nanomolar ranges in different previous studies .…”