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Regulation of the Cell Cycle and DNA Damage-Induced Checkpoint Activation

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RnDSy-lu-2945 Regulation of the Cell Cycle and DNA Damage-Induced Checkpoint Activation IR UV IR Stalled Replication Forks/ BRCA1 Rad50 Long Stretches of ss-DNA Rad50 Mre11 BRCA1 Nbs1 Rad9-Rad1-Hus1 Mre11 RPA MDC1 γ-H2AX DNA Pol α/Primase RFC2-5 MDC1 Nbs1 53BP1 MCM2-7 53BP1 γ-H2AX Rad17 Claspin MCM10 Rad9-Rad1-Hus1 TopBP1 CDC45 G1/S Checkpoint Intra-S-Phase RFC2-5 ATM ATR TopBP1 Rad17 ATRIP ATM Checkpoint Claspin Chk2 Chk1 Chk2 Chk1 ATR Rad50 ATRIP Mre11 FANCD2 Ubiquitin MDM2 MDM2 Nbs1 CDC25A Rad50 Mre11 BRCA1 Ub-mediated Phosphatase p53 CDC25A Ubiquitin p53 FANCD2 Phosphatase Degradation Nbs1 p53 p53 CDK2 p21 p21 BRCA1 Ub-mediated SMC1 Degradation Cyclin E/A SMC1 CDK2 Slow S Phase CDC45 Progression p21 DNA Pol α/Primase Slow S Phase p21 Cyclin E Progression Maintenance of Inhibition of New CDC6 CDT1 CDC45 G1/S Arrest Origin Firing ORC MCM2-7 MCM2-7 Recovery of Stalled Replication Forks Inhibition of MCM10 MCM10 Replication Origin Firing DNA Pol α/Primase ORI CDC6 CDT1 MCM2-7 ORC S Phase Delay MCM2-7 MCM10 MCM10 ORI Geminin EGF EGF R GAB-1 CDC6 CDT1 ORC MCM2-7 PI 3-Kinase p70 S6K MCM2-7 S6 Protein Translation Pre-RC (G1) GAB-2 MCM10 GSK-3 TSC1/2 MCM10 ORI PIP2 TOR Promotes Replication CAK EGF Origin Firing Origin PIP3 Activation CDK2 EGF R Akt CDC25A PDK-1 Phosphatase Cyclin E/A SHIP CIP/KIP (p21, p27, p57) (Active) PLCγ PP2A (Active) PTEN CDC45 PIP2 CAK Unwinding RPA CDC7 CDK2 IP3 DAG (Active) Positive DBF4 α Feedback CDC25A DNA Pol /Primase Cyclin E Loop Phosphatase PKC ORC RAS CDK4/6 CDK2 (Active) Cyclin E MCM10 CDC45 RPA IP Receptor Ca2+ 3 Cyclin D MCM10 EGF MCM2-7 ORI DNA Pol α/Primase (Active) Wee1 Cyclin E SOS RAF MEK1/2 CAK 1 CDK2 CDC6 CDT1 MCM2-7 EGF R 2 (Inactive) Src Lagging Strand RPA Jak MKP Myc Cyclin D MCM10 MCM2-7 ELK-1 Cyclin E DNA Pol δ/ε CDC25A Phosphatase Rb Cyclin E DNA Ligase STAT Other S Phase Elongation RFC ERK1/2 Genes FEN-1 PCNA RFC CDK2 DNA Ligase DNA Pol δ/ε STAT dimer Gene Transcription Rb E2F DP DNA Pol α/Primase Cyclin E Leading Strand PCNA FEN-1 RPA (Lagging Strand) CDK4/6 CDK2 Cyclin D RFC S Cyclin A MCM2-7 MCM10 G1 DNA Pol δ/ε CDC45 Direction of Fork Movement M CDK1 G2 Cyclin A Prophase CDK1 Spindle Assembly Metaphase Cyclin B Checkpoint Bub-1 CENP-E Bub-3 Mitotic MAD1 BubR1 G2/M Checkpoint Checkpoint Chromatin Complex MAD2 CDC20 Spindle Fibers Condensation CDK1 Cyclin B (Microtubules) Chromosomal APC/C Passenger IR UV Complex Separase Ubiquitin INCENP Mitotic Checkpoint BRCA1 Rad50 Borealin Protein Recruitment Mre11 Nbs1 Rad9-Rad1-Hus1 Securin C-TAK1 MDC1 Survivin Aurora B γ-H2AX 14-3-3 53BP1 RFC2-5 Centromere Metaphase Plate Bipolar Proteasome Microtubule } Rad17 CDC25A,B,C Phosphatase Claspin Stabilization Sister Chromatids (Inactive) p38 TopBP1 Cohesin Complexes ATM ATR MCAK MAPKAPK-2 ATRIP Myt1 Plk1 CDC25A,B,C Phosphatase (Active) Chk2 Chk1 Cyclin B CDK1 Positive (Inactive) Feedback MDM2 MDM2 Loop p53 CDC25A,B,C p53 Phosphatase CDK1 Cyclin B Kinetochore 14-3-3 Sequestration or Ub-mediated p21 Plk1 p21 CAK Degradation 14-3-3σ Mitotic Events CDK1 Cyclin B Export 14-3-3σ p53 GADD45α p53 GADD45α CENP-A (Activ Prophase) (Prophase) Centrioles Wee1 Wee1 Anaphase (↑Activity) (↑Activity) Cytoplasmic p21 p21 Substrates CDK1 Plk1 14-3-3σ Cyclin B 14-3-3σ Import Wee1 (Prophase) GADD45α GADD45α G2 M Cyclin B Maintenance of Nuclear Substrates CDK1 G2/M Arrest (Inactive) CDC25A,B,C Inhibition of Phosphatase M Phase (Active) Decondensing CDK1 Cyclin B Chromosomes CAK (Activ Prophase) CDK1 Cyclin B Cleavage Furrow Telophase (Cytokinesis) ContractileContractile Ringring (actin)(Actin) Regulators of Cell Cycle Progression CellSensors Cycle Checkpoint Proteins P Activating Phosphorylation P Inactivating Phosphorylation G2 - Second Gap Phase Sensors Mammalian Protein(s) Complete Name Basic Checkpoint Function G1 - First Gap Phase Mammalian Protein(s) Complete Name Basic Cell Cycle Function Sensors: Proteins that recognize and bind to damaged DNA to initiate signal transduction pathways that inhibit cell cycle progression and promote DNA repair or apoptosis. 14th DEAE elution fraction Mammalian Protein(s) Complete Name Basic Cell Cycle Function 14-3-3 Sequesters CDC25s or CDK1-Cyclin B in the cytoplasm to inhibit the G2/M transition Sensors CAK CDK-Activating Kinase Involved in CDK-Cyclin activation; Phosphorylates T160/161 of CDKs and 3.3 migration pattern Rad9-Rad1-Hus1 (9-1-1 Complex) Radiation Sensitive 9-Radiation Sensitive 1-Hydroxyurea Sensitive 1 Heterotrimeric DNA-binding complex that coordinates checkpoint signaling and DNA repair CAK CDK-Activating Kinase Involved in CDK-Cyclin activation; Phosphorylates T160/161 of CDKs Sensors CDC25A Cell Division Cycle 25A Dual-specificity phosphatase that removes inhibitory phosphates at T14 and Y15 of CDKs g-H2AX Histone H2A variant X Recognizes and binds to DNA double-strand breaks (DSBs) CDK-Cyclin complex activated at the G1/S transition; Phosphorylates Rb and other substrates Three different dual-specificity phosphatases that promote the G2/M transition by removing inhibitory CDK2-Cyclin E Cyclin-Dependent Kinase 2-Cyclin E CDC25A,B,C Cell Division Cycle 25A, B, C to promote S phase phosphates from CDK1 at T14 and Y15 Mre11-Rad50-Nbs1 (M/R/N Complex) Meiotic Recombination 11-Radiation Sensitive 50-Nijmegen Breakage Syndrome 1 Recruits and activates ATM at DNA DSBs CDK1 - Cyclin B (CDC2) Cyclin-Dependent Kinase 1-Cyclin B CDK-Cyclin complex required for the G2/M transition; Phosphorylates multiple substrates to promote mitosis CDK4/6-Cyclin D Cyclin-Dependent Kinase 4/6-Cyclin D CDK-Cyclin complexes activated in G1 to promote cell cycle progression; Phosphorylate Rb and other substrates Rad17 Radiation Sensitive 17 Loads the 9-1-1 complex onto damaged DNA along with RFC2-5 CDK-Interacting Protein 1/ Family of proteins that includes p21, p27, and p57 which bind CDK/Cyclin complexes in the nucleus C-TAK1 CDC25C-Associated Kinase 1 Protein kinase that negatively regulates CDC25C to inhibit the G2/M transition CIP/KIP Membrane-Associated Tyrosine- Protein kinase that negatively regulates cytoplasmic CDK1-Cyclin B by inhibitory phosphorylation of CDK1 RFC2-5 Replication Factor C 2-5 Loads the 9-1-1 complex onto damaged DNA along with Rad17 CDK Inhibitory Protein 1 to inhibit CDK activity Myt1 and Threonine-specific CDC2 Inhibitory Kinase at T14 and Y15 E2 Promoter Binding Factor/ Protein complex that activates the transcription of genes whose products are important for promoting Mediators: Scaffolding proteins that form multiprotein complexes at sites of DNA damage to recruit transducers and maintain checkpoint activation. E2F/DP Dimerization Partner DNA replication Protein kinase that phosphorylates CDC25 and Cyclin B to promote their nuclear translocation at the mitotic Plk1 Polo-like Kinase 1 53BP1 p53 Binding Protein 1 Scaffolding protein at DNA DSBs; Recruits other checkpoint/repair proteins Hypophosphorylated form recruits histone deacetylase to the promoters of E2F-regulated genes to inhibit transition; Negatively regulates the Myt1 and Wee1 kinases Rb Retinoblastoma Protein Protein kinase that negatively regulates CDK-Cyclin complexes in the nucleus by inhibitory phosphorylation their expression; Rb phosphorylation allows E2F-DP activity Wee1 Wee1 BRCA1 Breast Cancer 1 Scaffolding protein at DNA DSBs; DNA repair and recombination Wee1 Wee1 Protein kinase that negatively regulates CDK-Cyclin complexes by inhibitory phosphorylation of CDKs at Y15 of CDKs at Y15 Mediators Claspin Claspin Bridges ATR and Chk1 to facilitate Chk1 activation M phase - Mitosis Mediators S phase - DNA Replication Mammalian Protein(s) Complete Name Basic Cell Cycle Function MDC1 Mediator of DNA Damage Checkpoint 1 Scaffolding protein at DNA DSB sites; Recruits other checkpoint/repair proteins Mammalian Protein(s) Complete Name Basic Cell Cycle Function Chromosomal Passenger Complex (CPC) Mediators TopBP1 Topoisomerase Binding Protein 1 Implicated in ATR activation; Binds to Rad9 in the 9-1-1 complex to promote ATR-mediated Chk1 phosphorylation Pre-Replication Complex (Pre-RC) Enzymatic core of the CPC; Mitotic centromere kinase that ensures proper chromosome alignment; Replication licensing factor involved in loading the MCM2-7 helicase complex onto origins (ORI); Transducers:Mediators Kinases that are activated to transmit damage signals to effector molecules in the cell. CDC6 Cell Division Cycle 6 Aurora B Aurora B Stabilizes microtubule-kinetochore attachments; Required for lack of tension checkpoint response; Inhibits re-replication Regulates cytokinesis ATM Ataxia Telangiectasia-Mutated Phosphorylates multiple substrates in response to DNA DSBs Replication licensing factor involved in loading the MCM2-7 helicase complex onto origins; CDT1 CDC10-Dependent Transcript 1 Borealin Borealin Promotes binding of Survivin and INCENP in the CPC ATR: Phosphorylates multiple substrates in response to DNA damage that induces long stretches of RPA-coated ss-DNA such as stalled Inhibits re-replication ATR-ATRIP ATR: ATM and Rad3-related; ATRIP: ATR-Interacting Protein replication forks, or UV-induced DNA damage; ATRIP: Interacts with RPA and regulates the recruitment of ATR to sites of DNA damage Inhibitor of CDT1; Prevents origin licensing from S phase to metaphase by blocking the loading of the INCENP Inner Centromere Protein Stabilizes the CPC; Regulates Aurora B activation Geminin Geminin MCM2-7 helicase complex Chk1 Checkpoint Kinase 1 Kinase activated by ATR via phosphorylation; Phosphorylates and inactivates CDC25s Localizes the CPC to centromeres or the central spindle; Involved
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  • Orpl, a Member of the Cdcl8/Cdc6 Family of S-Phase Regulators, Is Homologous to a Component of the Origin Recognition Complex M

    Orpl, a Member of the Cdcl8/Cdc6 Family of S-Phase Regulators, Is Homologous to a Component of the Origin Recognition Complex M

    Proc. Natl. Acad. Sci. USA Vol. 92, pp. 12475-12479, December 1995 Genetics Orpl, a member of the Cdcl8/Cdc6 family of S-phase regulators, is homologous to a component of the origin recognition complex M. MuzI-FALCONI AND THOMAS J. KELLY Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, MD 21205 Contributed by Thomas J. Kelly, September 11, 1995 ABSTRACT cdc18+ of Schizosaccharomyces pombe is a is the cdcJ8+ gene (1, 15). Expression of cdcJ8+ from a periodically expressed gene that is required for entry into S heterologous promoter is sufficient to rescue the lethality of a phase and for the coordination of S phase with mitosis. cdc18+ conditional temperature-sensitive (ts) cdc O's mutant. The is related to the Saccharomyces cerevisiae gene CDC6, which has cdcJ8+ gene product, a 65-kDa protein, is essential for the also been implicated in the control of DNA replication. We GI/S transition. Moreover, p65cdclS is a highly labile protein have identified a new Sch. pombe gene, orpl1, that encodes an whose expression is confined to a narrow window at the G,/S 80-kDa protein with amino acid sequence motifs conserved in boundary (unpublished data). These properties are consistent the Cdc18 and Cdc6 proteins. Genetic analysis indicates that with the hypothesis that Cdc18 may play an important role in orpi + is essential for viability. Germinating spores lacking the regulating the initiation of DNA replication at S phase. The orpl + gene are capable of undergoing one or more rounds of Cdc18 protein is homologous to the budding yeast Cdc6 DNA replication but fail to progress further, arresting as long protein, which may have a similar function (16).