Project description:Transcriptional silencing of hypermethylated tumor suppressor genes is a hallmark of tumorigenesis, though the underlying mechanism remains enigmatic. In this study, we find Methyl-CpG-binding domain protein 2 (MBD2) forms nuclear condensate in diverse cancer cells, where it assembles and navigates the chromatin remodeler NuRD complex to these gene loci for transcriptional suppression, thus fueling tumor growth. Disturbance of MBD2 condensate reduces the level of NuRD complex-specific proteins, destabilizes heterochromatin foci, facilitates chromatin relaxation, and consequently impedes tumor progression. We demonstrate that MBD2 condensate is redox sensitive mediated by Cys359. Prooxidative interventions disperse MBD2-NuRD condensate, thereby alleviating the transcriptional repression of tumor suppressor genes. Our findings illuminate a hitherto unappreciated function of MBD2 condensate in sustaining a repressive chromatin state essential for cancer cell proliferation and suggest an oxidative stress targeting approach for malignancies with excessive MBD2 condensate.
Project description:Transcriptional silencing of hypermethylated tumor suppressor genes is a hallmark of tumorigenesis, though the underlying mechanism remains enigmatic. In this study, we find Methyl-CpG-binding domain protein 2 (MBD2) forms nuclear condensate in diverse cancer cells, where it assembles and navigates the chromatin remodeler NuRD complex to these gene loci for transcriptional suppression, thus fueling tumor growth. Disturbance of MBD2 condensate reduces the level of NuRD complex-specific proteins, destabilizes heterochromatin foci, facilitates chromatin relaxation, and consequently impedes tumor progression. We demonstrate that MBD2 condensate is redox sensitive mediated by Cys359. Prooxidative interventions disperse MBD2-NuRD condensate, thereby alleviating the transcriptional repression of tumor suppressor genes. Our findings illuminate a hitherto unappreciated function of MBD2 condensate in sustaining a repressive chromatin state essential for cancer cell proliferation and suggest an oxidative stress targeting approach for malignancies with excessive MBD2 condensate.
Project description:Transcriptional silencing of hypermethylated tumor suppressor genes is a hallmark of tumorigenesis, though the underlying mechanism remains enigmatic. In this study, we find Methyl-CpG-binding domain protein 2 (MBD2) forms nuclear condensate in diverse cancer cells, where it assembles and navigates the chromatin remodeler NuRD complex to these gene loci for transcriptional suppression, thus fueling tumor growth. Disturbance of MBD2 condensate reduces the level of NuRD complex-specific proteins, destabilizes heterochromatin foci, facilitates chromatin relaxation, and consequently impedes tumor progression. We demonstrate that MBD2 condensate is redox sensitive mediated by Cys359. Prooxidative interventions disperse MBD2-NuRD condensate, thereby alleviating the transcriptional repression of tumor suppressor genes. Our findings illuminate a hitherto unappreciated function of MBD2 condensate in sustaining a repressive chromatin state essential for cancer cell proliferation and suggest an oxidative stress targeting approach for malignancies with excessive MBD2 condensate.
Project description:Transcriptional silencing of hypermethylated tumor suppressor genes is a hallmark of tumorigenesis, though the underlying mechanism remains enigmatic. In this study, we find Methyl-CpG-binding domain protein 2 (MBD2) forms nuclear condensate in diverse cancer cells, where it assembles and navigates the chromatin remodeler NuRD complex to these gene loci for transcriptional suppression, thus fueling tumor growth. Disturbance of MBD2 condensate reduces the level of NuRD complex-specific proteins, destabilizes heterochromatin foci, facilitates chromatin relaxation, and consequently impedes tumor progression. We demonstrate that MBD2 condensate is redox sensitive mediated by Cys359. Prooxidative interventions disperse MBD2-NuRD condensate, thereby alleviating the transcriptional repression of tumor suppressor genes. Our findings illuminate a hitherto unappreciated function of MBD2 condensate in sustaining a repressive chromatin state essential for cancer cell proliferation and suggest an oxidative stress targeting approach for malignancies with excessive MBD2 condensate.
Project description:To obtain a comprehensive and quantitative view on MBD2 vs MBD3-NuRD complex stoichiometry, we performed biotin co-immunoprecipitations in Mbd3 KO ES cells expressing either biotin-tagged MBD2a or MBD3a and identified known NuRD complex members using label-free mass spectrometry (Supplementary Fig. 8b-c). We then calculated the intensity-based absolute quantification (iBAQ) values of the most predominant and statistically significant MBD-interacting proteins in both cell lines, which can be used to estimate the relative abundance. While we observe very similar complex composition between MBD2a-NuRD and MBD3a-NuRD, peptides shared between SALL1-4 proteins show a preferred interaction with the MBD2a-NuRD complex.