AI Insight
This study reanalyzes data from a previous experiment (CLAP) that claimed PRC2, a protein complex essential for gene silencing during cell differentiation, does not bind RNA inside living cells. The authors demonstrate that PRC2 does in fact directly interact with RNA in cells, and that the earlier negative conclusion resulted from a flawed data normalization step that artificially deflated enrichment scores in low-complexity samples. Using Halo-tagged PRC2 subunits in mixed human-mouse cell populations, the researchers show species-specific RNA enrichment consistent with genuine direct binding.
Why it matters
PRC2 plays a critical role in development and is implicated in various cancers, so clarifying whether it binds RNA in living cells is essential for understanding how gene repression is regulated and for identifying potential therapeutic targets.
⚠️ Preprint – Noch nicht peer-reviewed
Dieser Artikel wurde noch nicht von unabhängigen Experten begutachtet. Die Ergebnisse sind vorläufig und sollten mit Vorsicht interpretiert werden.
Polycomb Repressive Complex 2 (PRC2) maintains repression of genes specific for other cell differentiation states. PRC2 binds RNA in vitro with a preference for G-rich sequences. UV-based crosslinking coupled with immunoprecipitation (CLIP) experiments have shown that PRC2 also binds RNA in cells. Recently, Guo et al reported that a stringent denaturing variant of CLIP called CLAP did not detect PRC2 RNA binding in cells. We present a reanalysis of CLAP data that supports direct interaction of PRC2 with RNA in cells. CLAP for Halo-tagged PRC2 subunits from mixed populations of human and mouse cells specifically enriched for RNA from the species in which the proteins were tagged. The lack of apparent PRC2 RNA binding in Guo and colleagues’ analysis stems from a scaling step that deflates enrichment scores for low-complexity CLAP samples. Our findings pave the way for studies seeking to determine the physiological roles of PRC2 RNA binding activity.
Source: Denaturing purifications support direct interaction between PRC2 and RNA in cells