DNA damage response (DDR) in ribosomal genes and mechanisms of DNA repair in embryonic stem cells (ESCs) are less explored nuclear events. DDR in ESCs should be unique due to their high proliferation rate, expression of pluripotency factors, and specific chromatin signature. Given short population doubling time and fast progress through G1 phase, ESCs require a sustained production of rRNA, which leads to the formation of large and prominent nucleoli. Although transcription of rRNA in the nucleolus is relatively well understood, little is known about DDR in this nuclear compartment. Here, we directed formation of double-strand breaks in rRNA genes with I- PpoI endonuclease, and we studied nucleolar morphology, DDR, and chromatin modifications. We observed a pronounced formation of I- PpoI-induced nucleolar caps, positive on BRCA1, NBS1, MDC1, γH2AX, and UBF1 proteins. We showed interaction of nucleolar protein TCOF1 with HDAC1 and TCOF1 with CARM1 after DNA injury. Moreover, H3R17me2a modification mediated by CARM1 was found in I- PpoI-induced nucleolar caps. Finally, we report that heterochromatin protein 1 is not involved in DNA repair of nucleolar caps.

• Klíčová slova
• CARM1, DNA repair, HDAC1, NBS1, PpoI, chromatin, nucleolus,
• MeSH
• acetylace MeSH
• arginin metabolismus   MeSH
• buněčné jadérko genetika   ultrastruktura   MeSH
• buněčné linie MeSH
• dvouřetězcové zlomy DNA * MeSH
• embryonální kmenové buňky metabolismus   ultrastruktura   MeSH
• fosfoproteiny metabolismus   MeSH
• geny rRNA MeSH
• histondeacetylasa 1 metabolismus   MeSH
• histony metabolismus   MeSH
• intracelulární signální peptidy a proteiny MeSH
• jaderné proteiny metabolismus   MeSH
• metylace MeSH
• myši MeSH
• oprava DNA MeSH
• proteinarginin-N-methyltransferasy metabolismus   MeSH
• RNA ribozomální genetika   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• arginin MeSH
• coactivator-associated arginine methyltransferase 1 MeSH Prohlížeč
• fosfoproteiny MeSH
• Hdac1 protein, mouse MeSH Prohlížeč
• histondeacetylasa 1 MeSH
• histony MeSH
• intracelulární signální peptidy a proteiny MeSH
• jaderné proteiny MeSH
• proteinarginin-N-methyltransferasy MeSH
• RNA ribozomální MeSH
• Tcof1 protein, mouse MeSH Prohlížeč