DNA replication is a highly coordinated process that is initiated at multiple replication origins in eukaryotes. These origins are bound by the origin recognition complex (ORC), which subsequently recruits the Mcm2-7 replicative helicase in a Cdt1/Cdc6-dependent manner. In budding yeast, two essential replication factors, Sld2 and Mcm10, are then important for the activation of replication origins. In humans, the putative Sld2 homolog, RECQ4, interacts with MCM10. Here, we have identified two mutants of human RECQ4 that are deficient in binding to MCM10. We show that these RECQ4 variants are able to complement the lethality of an avian cell RECQ4 deletion mutant, indicating that the essential function of RECQ4 in vertebrates is unlikely to require binding to MCM10. Nevertheless, we show that the RECQ4-MCM10 interaction is important for efficient replication origin firing.

• Klíčová slova
• Chromosome Section, DNA replication, RecQ helicases, minichromosome maintenance proteins,
• MeSH
• apoptóza MeSH
• chromatin genetika   MeSH
• helikasy RecQ genetika   metabolismus   MeSH
• imunoenzymatické techniky MeSH
• imunoprecipitace MeSH
• interakční proteinové domény a motivy MeSH
• kur domácí genetika   MeSH
• kvantitativní polymerázová řetězová reakce MeSH
• lidé MeSH
• MCM komplex, komponenta 2 genetika   metabolismus   MeSH
• MCM komplex, komponenta 7 genetika   metabolismus   MeSH
• MCM proteiny genetika   metabolismus   MeSH
• messenger RNA genetika   MeSH
• molekulární sekvence - údaje MeSH
• nádorové buňky kultivované MeSH
• nádory kostí genetika   metabolismus   patologie   MeSH
• osteosarkom genetika   metabolismus   patologie   MeSH
• polymerázová řetězová reakce s reverzní transkripcí MeSH
• povrchová plasmonová rezonance MeSH
• proliferace buněk MeSH
• průtoková cytometrie MeSH
• replikace DNA * MeSH
• replikační počátek genetika   MeSH
• Saccharomyces cerevisiae genetika   metabolismus   MeSH
• sekvence aminokyselin MeSH
• sekvenční homologie aminokyselin MeSH
• western blotting MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• chromatin MeSH
• helikasy RecQ MeSH
• MCM komplex, komponenta 2 MeSH
• MCM komplex, komponenta 7 MeSH
• MCM proteiny MeSH
• MCM10 protein, human MeSH Prohlížeč
• MCM2 protein, human MeSH Prohlížeč
• MCM7 protein, human MeSH Prohlížeč
• messenger RNA MeSH
• RECQL4 protein, human MeSH Prohlížeč

Cdc7 kinase regulates DNA replication. However, its role in DNA repair and recombination is poorly understood. Here we describe a pathway that stabilizes the human Cdc7-ASK (activator of S-phase kinase; also called Dbf4), its regulation, and its function in cellular responses to compromised DNA replication. Stalled DNA replication evoked stabilization of the Cdc7-ASK (Dbf4) complex in a manner dependent on ATR-Chk1-mediated checkpoint signaling and its interplay with the anaphase-promoting complex/cyclosome(Cdh1) (APC/C(Cdh1)) ubiquitin ligase. Mechanistically, Chk1 kinase inactivates APC/C(Cdh1) through degradation of Cdh1 upon replication block, thereby stabilizing APC/C(Cdh1) substrates, including Cdc7-ASK (Dbf4). Furthermore, motif C of ASK (Dbf4) interacts with the N-terminal region of RAD18 ubiquitin ligase, and this interaction is required for chromatin binding of RAD18. Impaired interaction of ASK (Dbf4) with RAD18 disables foci formation by RAD18 and hinders chromatin loading of translesion DNA polymerase η. These findings define a novel mechanism that orchestrates replication checkpoint signaling and ubiquitin-proteasome machinery with the DNA damage bypass pathway to guard against replication collapse under conditions of replication stress.

• Klíčová slova
• APC/CCdh1, Cdc7, Chk1, DNA lesion bypass, RAD18, replication stress,
• MeSH
• ATM protein metabolismus   MeSH
• CD antigeny MeSH
• checkpoint kinasa 1 MeSH
• geny APC fyziologie   MeSH
• HEK293 buňky MeSH
• HeLa buňky MeSH
• kadheriny metabolismus   MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• poškození DNA * MeSH
• protein-serin-threoninkinasy metabolismus   MeSH
• proteinkinasy metabolismus   MeSH
• proteiny buněčného cyklu genetika   metabolismus   MeSH
• replikace DNA * MeSH
• signální transdukce MeSH
• stabilita enzymů MeSH
• vazba proteinů MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• ATM protein MeSH
• ATR protein, human MeSH Prohlížeč
• CD antigeny MeSH
• CDC7 protein, human MeSH Prohlížeč
• CDH1 protein, human MeSH Prohlížeč
• checkpoint kinasa 1 MeSH
• CHEK1 protein, human MeSH Prohlížeč
• DBF4 protein, human MeSH Prohlížeč
• kadheriny MeSH
• protein-serin-threoninkinasy MeSH
• proteinkinasy MeSH
• proteiny buněčného cyklu MeSH