Person:
Tolstorukov, Michael

Profile Picture

Email Address

AA Acceptance Date

Birth Date

Research Projects

Organizational Units

Job Title

Last Name

Tolstorukov

First Name

Michael

Name

Tolstorukov, Michael
Author's Publications: search.filters.isAuthorOfPublication.ae42e831-0749-4f96-aadb-80475655f727

Search Results

Now showing 1 - 2 of 2
  • Thumbnail Image
    Publication
    SMARCB1-mediated SWI/SNF complex function is essential for enhancer regulation
    (2016) Wang, Xiaofeng; Lee, Ryan; Alver, Burak; Haswell, Jeffrey; Wang, Su; Mieczkowski, Jakub; Drier, Yotam; Gillespie, Shawn M.; Archer, Tenley; Wu, Jennifer; Tzvetkov, Evgeni P.; Troisi, Emma C.; Pomeroy, Scott; Biegel, Jaclyn A.; Tolstorukov, Michael; Bernstein, Bradley; Park, Peter; Roberts, Charles W. M.
    SMARCB1 (SNF5/INI1/BAF47), a core subunit of the SWI/SNF (BAF) chromatin remodeling complex1,2, is inactivated in nearly all pediatric rhabdoid tumors3–5. These aggressive cancers are among the most genomically stable6–8, suggesting an epigenetic mechanism by which SMARCB1 loss drives transformation. Here, we show that despite indistinguishable mutational landscapes, human rhabdoid tumors show distinct enhancer H3K27ac signatures, which reveal remnants of differentiation programs. We show that SMARCB1 is required for the integrity of SWI/SNF complexes and that its loss alters enhancer targeting – markedly impairing SWI/SNF binding to typical enhancers, particularly those required for differentiation, while maintaining SWI/SNF binding at super-enhancers. We show that these retained super-enhancers are essential for rhabdoid tumor survival, including some that are shared across all subtypes, such as SPRY1, and other lineage-specific super-enhancers, like SOX2 in brain-derived rhabdoid tumors. Taken together, our findings reveal a novel chromatin-based epigenetic mechanism underlying the tumor suppressive activity of SMARCB1.
  • Thumbnail Image
    Publication
    Enhanced chromatin accessibility of the dosage compensated Drosophila male X-chromosome requires the CLAMP zinc finger protein
    (Public Library of Science, 2017) Urban, Jennifer; Kuzu, Guray; Bowman, Sarah; Scruggs, Benjamin; Henriques, Telmo; Kingston, Robert; Adelman, Karen; Tolstorukov, Michael; Larschan, Erica
    The essential process of dosage compensation is required to equalize gene expression of X-chromosome genes between males (XY) and females (XX). In Drosophila, the conserved Male-specific lethal (MSL) histone acetyltransferase complex mediates dosage compensation by increasing transcript levels from genes on the single male X-chromosome approximately two-fold. Consistent with its increased levels of transcription, the male X-chromosome has enhanced chromatin accessibility, distinguishing it from the autosomes. Here, we demonstrate that the non-sex-specific CLAMP (Chromatin-linked adaptor for MSL proteins) zinc finger protein that recognizes GA-rich sequences genome-wide promotes the specialized chromatin environment on the male X-chromosome and can act over long genomic distances (~14 kb). Although MSL complex is required for increasing transcript levels of X-linked genes, it is not required for enhancing global male X-chromosome chromatin accessibility, and instead works cooperatively with CLAMP to facilitate an accessible chromatin configuration at its sites of highest occupancy. Furthermore, CLAMP regulates chromatin structure at strong MSL complex binding sites through promoting recruitment of the Nucleosome Remodeling Factor (NURF) complex. In contrast to the X-chromosome, CLAMP regulates chromatin and gene expression on autosomes through a distinct mechanism that does not involve NURF recruitment. Overall, our results support a model where synergy between a non-sex-specific transcription factor (CLAMP) and a sex-specific cofactor (MSL) creates a specialized chromatin domain on the male X-chromosome.