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bioRxiv · 10.1101/322065

SWI/SNF remains localized to chromatin in the presence of SCHLAP1

Abstract

SCHLAP1 is a long-noncoding RNA that is prognostic for progression to metastatic prostate cancer and promotes an invasive phenotype. SCHLAP1 is reported to function by depleting the core SWI/SNF subunit, SMARCB1, from the genome. SWI/SNF is a large, multi-subunit, chromatin remodeling complex that can be combinatorially assembled to yield hundreds to thousands of distinct complexes. Here, we investigated the hypothesis that SCHLAP1 affects only specific forms of SWI/SNF and that the remaining SWI/SNF complexes were important for the increased invasion in SCHLAP1 expressing prostate cells. Using several assays we found that SWI/SNF is not depleted from the genome by SCHLAP1 expression. We find that SCHLAP1 induces changes to chromatin openness but is not sufficient to drive changes in histone modifications. Additionally, we show that SWI/SNF binds many coding and non-coding RNAs. Together these results suggest that SCHLAP1 has roles independent of canonical SWI/SNF and that SWI/SNF broadly interacts with RNA.

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Raab, J. R., Smith, K. N., Spear, C. C., Manner, C. J., Calabrese, J. M., Magnuson, T.. 2018-05-14. SWI/SNF remains localized to chromatin in the presence of SCHLAP1. https://doi.org/10.1101/322065

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