Microsize antibodies for $99 | Learn More >>

Human Dna Replication Checkpoint

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Western Blotting

Background: The initiation of DNA replication in mammalian cells is a highly coordinated process that ensures duplication of the genome only once per cell division cycle. Origins of replication are dispersed throughout the genome, and their activities are regulated via the sequential binding of prereplication and replication factors. The origin recognition complex (ORC) is thought to be bound to chromatin throughout the cell cycle (1,2). The prereplication complex (Pre-RC) forms in late mitosis/early G1 phase beginning with the binding of CDT1 and cdc6 to the origin, which allows binding of the heterohexameric MCM2-7 complex. The MCM complex is thought to be the replicative helicase, and formation of the pre-RC is referred to as chromatin licensing. Subsequent initiation of DNA replication requires the activation of the S-phase promoting kinases CDK2 and cdc7. Cdc7, which is active only in complex with its regulatory subunit dbf4, phosphorylates MCM proteins bound to chromatin and allows binding of the replication factor cdc45 and DNA polymerase (3,4).Binding of CDT1 to geminin prevents pre-RC formation, and expression and degradation of geminin serve to regulate CDT1 activity (reviewed in 5). The interaction of CDT1 with MCM proteins is important in pre-RC formation and licensing (6,7). Both cdc6 and CDT1 are degraded by the ubiquitin proteasome pathway in response to DNA damage associated with rereplication (8).

$111
20 µl
$260
100 µl
APPLICATIONS
REACTIVITY
Hamster, Human, Monkey, Mouse, Rat

Application Methods: Western Blotting

Background: The initiation of DNA replication in mammalian cells is a highly coordinated process that ensures duplication of the genome only once per cell division cycle. Origins of replication are dispersed throughout the genome, and their activities are regulated via the sequential binding of pre-replication and replication factors. The origin recognition complex (ORC) is thought to be bound to chromatin throughout the cell cycle (1,2). The pre-replication complex (Pre-RC) forms in late mitosis/early G1 phase beginning with the binding of CDT1 and cdc6 to the origin, which allows binding of the heterohexameric MCM2-7 complex. The MCM complex is thought to be the replicative helicase, and formation of the pre-RC is referred to as chromatin licensing. Subsequent initiation of DNA replication requires the activation of the S-phase promoting kinases cdk2 and cdc7. Cdc7, which is active only in complex with its regulatory subunit dbf4, phosphorylates MCM proteins bound to chromatin and allows binding of the replication factor cdc45 and DNA polymerase (3,4).Replication licensing is controlled in part by the degradation of cdc6 in quiescent cells. Phosphorylation of cdc6 by cdk2 prevents its degradation, allowing pre-replication complexes to form (5). Cdc6 has recently been shown to play an important role in the intra-S-phase p21 Waf1/Cip1-dependent DNA damage response (6,7). Both cdc6 and CDT1 are degraded by the ubiquitin proteasome pathway in response to DNA damage associated with re-replication (8).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey

Application Methods: Immunofluorescence (Immunocytochemistry), Immunoprecipitation, Western Blotting

Background: The initiation of DNA replication in mammalian cells is a highly coordinated process that ensures duplication of the genome only once per cell division cycle. Origins of replication are dispersed throughout the genome, and their activities are regulated via the sequential binding of prereplication and replication factors. The origin recognition complex (ORC) is thought to be bound to chromatin throughout the cell cycle (1,2). The prereplication complex (Pre-RC) forms in late mitosis/early G1 phase beginning with the binding of CDT1 and cdc6 to the origin, which allows binding of the heterohexameric MCM2-7 complex. The MCM complex is thought to be the replicative helicase, and formation of the pre-RC is referred to as chromatin licensing. Subsequent initiation of DNA replication requires the activation of the S-phase promoting kinases CDK2 and cdc7. Cdc7, which is active only in complex with its regulatory subunit dbf4, phosphorylates MCM proteins bound to chromatin and allows binding of the replication factor cdc45 and DNA polymerase (3,4).Binding of CDT1 to geminin prevents pre-RC formation, and expression and degradation of geminin serve to regulate CDT1 activity (reviewed in 5). The interaction of CDT1 with MCM proteins is important in pre-RC formation and licensing (6,7). Both cdc6 and CDT1 are degraded by the ubiquitin proteasome pathway in response to DNA damage associated with rereplication (8).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Immunofluorescence (Immunocytochemistry), Immunoprecipitation, Western Blotting

Background: The initiation of DNA replication in mammalian cells is a highly coordinated process that ensures duplication of the genome only once per cell division cycle. Origins of replication are dispersed throughout the genome and their activities are regulated via the sequential binding of pre-replication and replication factors. The origin recognition complex (ORC) is thought to bind to chromatin throughout the cell cycle (1,2). The pre-replication complex (Pre-RC) forms in late mitosis/early G1 phase with the binding of CDT1 and cdc6 to the origin, which allows binding of the heterohexameric MCM2-7 complex. The MCM complex is thought to be the replicative helicase and formation of the Pre-RC is referred to as chromatin licensing. Subsequent initiation of DNA replication requires the activation of the S-phase promoting kinases cdk2 and cdc7. Cdc7 phosphorylates MCM proteins bound to chromatin and, in conjunction with CDT1, recruits the replication factor cdc45 (3-5). Cdc45 is required for formation of pre-initiation complexes at the G1/S transition and for activation of replication origins. The level of cdc45 protein expression is associated with the proliferative status of the cell or tissue. Terminally differentiated and senescent cells lack cdc45 and highly proliferative cell lines express high levels of cdc45 (6).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Western Blotting

Background: The initiation of DNA replication in mammalian cells is a highly coordinated process that ensures duplication of the genome only once per cell division cycle. Origins of replication are dispersed throughout the genome and their activities are regulated via the sequential binding of pre-replication and replication factors. The origin recognition complex (ORC) is thought to bind to chromatin throughout the cell cycle (1,2). The pre-replication complex (Pre-RC) forms in late mitosis/early G1 phase with the binding of CDT1 and cdc6 to the origin, which allows binding of the heterohexameric MCM2-7 complex. The MCM complex is thought to be the replicative helicase and formation of the Pre-RC is referred to as chromatin licensing. Subsequent initiation of DNA replication requires the activation of the S-phase promoting kinases cdk2 and cdc7. Cdc7 phosphorylates MCM proteins bound to chromatin and, in conjunction with CDT1, recruits the replication factor cdc45 (3-5). Cdc45 is required for formation of pre-initiation complexes at the G1/S transition and for activation of replication origins. The level of cdc45 protein expression is associated with the proliferative status of the cell or tissue. Terminally differentiated and senescent cells lack cdc45 and highly proliferative cell lines express high levels of cdc45 (6).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: DNA damage resulting from genotoxic stress activates cellular checkpoints that prevent or delay cell division until damaged DNA is repaired or the cell follows an apoptotic pathway. The Rad9 homolog A (Rad9A, Rad9) protein is part of a checkpoint protein complex that acts as an early sensor of DNA damage. Together with the HUS1 and Rad1 checkpoint proteins, Rad9 forms a heterotrimeric 9-1-1 complex with a ring structure similar to the processivity factor PCNA. The 9-1-1 complex induces multiple signaling pathways, including the ATM- and ATR-activated DNA repair pathways (1,2). A functional 9-1-1 complex is required for ATR-dependent S phase checkpoint signaling (3).The 9-1-1 complex interacts with DNA topoisomerase 2-binding protein 1 (TopBP1) in response to DNA damage, activating ATR and causing signal amplification through further recruitment of TopBP1 (4). The 9-1-1 complex interacts with DNA mismatch repair proteins MSH2, MSH3, and MSH6 to play a role in mismatch repair (5). During an error-free DNA damage tolerance process, the 9-1-1 complex cooperates with polyubiquitinated PCNA and Exo1 nuclease to support switching of the replicative polymerase to the undamaged template (6).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Western Blotting

Background: Originally identified in Xenopus (1), and later in human cells (2), claspin is a mediator of Chk1 signal transduction at the replication checkpoint and in response to DNA damage. Expression of claspin is cell cycle-regulated, with protein levels peaking at the S/G2 phase (2). Expression is negatively regulated by both proteosome- and caspase-mediated degradation (3), and stabilized by activation of Chk1 (4). Claspin is a chromatin-bound protein, and has been shown to interact with the PNCA complex in the absence of DNA damage (5). Following checkpoint activation it remains chromatin-bound but is released from the PCNA complex and is phosphorylated in an ATR-dependent manner. Phosphorylated claspin interacts with several components of the DNA damage response including BRCA1 (6) and Chk1 (7), leading to ATR-dependent phosphorylation on each of these proteins. Phosphorylated Rad17 has also been shown to bind to and regulate the phosphorylation of claspin (8). It has been proposed that claspin behaves as a tumor suppressor in come cases since down-regulation promotes apoptosis following genotoxic stress (2). Conversely, claspin seems to behave as an oncogene in other instances since overexpression promotes cellular proliferation (6). Upregulated claspin has been suggested to be a sensitive marker of abnormally proliferating cells (9).

$303
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Western Blotting

Background: The human checkpoint protein Rad17 and its fission and budding yeast orthologues (Schizosaccharomyces pombe Rad17 and Saccharomyces cerevisiae Rad24, respectively) are involved in the activation of checkpoint signals in response to DNA damage or disruption of DNA synthesis (1-4). Treatment of human cells with genotoxic agents induces ATM/ATR-dependent phosphorylation of Rad17 at Ser635 and Ser645. Rad17 phosphorylation is a critical early event during checkpoint signaling in DNA-damaged cells (5-7).

$303
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunoprecipitation, Western Blotting

Background: The human checkpoint protein Rad17 and its fission and budding yeast orthologues (Schizosaccharomyces pombe Rad17 and Saccharomyces cerevisiae Rad24, respectively) are involved in the activation of checkpoint signals in response to DNA damage or disruption of DNA synthesis (1-4). Treatment of human cells with genotoxic agents induces ATM/ATR-dependent phosphorylation of Rad17 at Ser635 and Ser645. Rad17 phosphorylation is a critical early event during checkpoint signaling in DNA-damaged cells (5-7).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Western Blotting

Background: The human checkpoint protein Rad17 and its fission and budding yeast orthologues (Schizosaccharomyces pombe Rad17 and Saccharomyces cerevisiae Rad24, respectively) are involved in the activation of checkpoint signals in response to DNA damage or disruption of DNA synthesis (1-4). Treatment of human cells with genotoxic agents induces ATM/ATR-dependent phosphorylation of Rad17 at Ser635 and Ser645. Rad17 phosphorylation is a critical early event during checkpoint signaling in DNA-damaged cells (5-7).

$260
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Western Blotting

Background: DNA damage resulting from genotoxic stress activates cellular checkpoints that prevent or delay cell division until either damaged DNA is repaired or the cell follows an apoptotic pathway. The Rad9 homolog A (Rad9A, Rad9) protein is part of a checkpoint protein complex that acts as an early sensor of DNA damage. Together with the Hus1 and Rad1 checkpoint proteins, Rad9 forms a heterotrimeric 9-1-1 complex with a ring structure similar to the processivity factor PCNA. The 9-1-1 complex induces multiple signaling pathways, including the ATM and ATR-activated DNA repair pathways (1,2). A functional 9-1-1 complex is required for ATR-dependent S phase checkpoint signaling (3).The 9-1-1 complex interacts with DNA topoisomerase 2-binding protein 1 (TopBP1) in response to DNA damage, activating ATR and causing signal amplification through further recruitment of TopBP1 (4). The 9-1-1 complex interacts with DNA mismatch repair proteins MSH2, MSH3, and MSH6 to play a role in mismatch repair (5). During an error-free DNA damage tolerance process, the 9-1-1 complex cooperates with polyubiquitinated PCNA and Exo1 nuclease to support switching of the replicative polymerase to the undamaged template (6).Research studies indicate that the two Rad9 paralogues (Rad9A and Rad9B) can both functionally complement one another and display distinct biological functions.Specifically, Rad9B senses nucleolar stress and causes a delay in the cell cycle at G1/S phase (7).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Western Blotting

Background: Similar to ubiquitin, NEDD8 is covalently linked to target proteins through an enzymatic cascade composed of NEDD8-specific E1 (activating)- and E2 (conjugating)-enzymes (1,2). The E2 ligase specific for NEDD8 is Ubc12 (3-5). Ubc12 forms a heterodimeric conjugate with NEDD8 in order to catalyze the transfer of NEDD8 from E1 to lysine side chains of target proteins (1,2). Well known targets of NEDD8 are cullin-based RING E3 ligases. Neddylation of cullin isoforms activates the related ubiquitin E3 complex by promoting its interaction with a cognate ubiquitin-E2 ligase (6-7). Neddylation of Cul-1 complexes containing βTrCP and SKP2 has been shown to be required for controlling the stability of important signaling targets such as IκB, NF-κB, and p27 Kip (8-10), thereby regulating cell cycle progression, signaling cascades, and developmental programming processes (11).

$111
20 µl
$260
100 µl
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Flow Cytometry, Immunoprecipitation, Western Blotting

Background: Cyclin-dependent kinase 2 (p33CDK2) is an important component of the cell cycle machinery. Like p34cdc2, kinase activity is regulated by phosphorylation state as well as association with a cyclin subunit and a CDK inhibitor. Inhibitory phosphorylation occurs on Thr14 and Tyr15 (1). Inhibition of CDK2-cyclin complexes can also be attributed to association with p27 Kip1 and p21 Waf1/Cip1 (2). Activation of CDK2 complexes requires dephosphorylation of Thr14 and Tyr15 by cdc25 phosphatase and phosphorylation of Thr160 (3), which is mediated by CAK, a complex of CDK7 and cyclin H (4). CDK2/cyclin E kinase activity is important for the G1 to S transition and phosphorylation of the Rb protein. During S-phase, active CDK2/cyclin A complexes predominate and phosphorylate E2F and the active CDK2 complex persists in the nucleus throughout G2 (5).

$262
3 nmol
300 µl
SignalSilence® CDK2 siRNA II from Cell Signaling Technology (CST) allows the researcher to specifically inhibit CDK2 expression using RNA interference, a method whereby gene expression can be selectively silenced through the delivery of double stranded RNA molecules into the cell. All SignalSilence® siRNA products from CST are rigorously tested in-house and have been shown to reduce target protein expression by western analysis.
REACTIVITY
Human

Background: Cyclin-dependent kinase 2 (p33CDK2) is an important component of the cell cycle machinery. Like p34cdc2, kinase activity is regulated by phosphorylation state as well as association with a cyclin subunit and a CDK inhibitor. Inhibitory phosphorylation occurs on Thr14 and Tyr15 (1). Inhibition of CDK2-cyclin complexes can also be attributed to association with p27 Kip1 and p21 Waf1/Cip1 (2). Activation of CDK2 complexes requires dephosphorylation of Thr14 and Tyr15 by cdc25 phosphatase and phosphorylation of Thr160 (3), which is mediated by CAK, a complex of CDK7 and cyclin H (4). CDK2/cyclin E kinase activity is important for the G1 to S transition and phosphorylation of the Rb protein. During S-phase, active CDK2/cyclin A complexes predominate and phosphorylate E2F and the active CDK2 complex persists in the nucleus throughout G2 (5).

$305
50 tests
100 µl
This Cell Signaling Technology antibody is conjugated to phycoerythrin (PE) and tested in-house for direct flow cytometry analysis in human cells. The antibody is expected to exhibit the same species cross-reactivity as the unconjugated CDK2 (78B2) Rabbit mAb #2546.
APPLICATIONS
REACTIVITY
Human, Monkey, Mouse, Rat

Application Methods: Flow Cytometry

Background: Cyclin-dependent kinase 2 (p33CDK2) is an important component of the cell cycle machinery. Like p34cdc2, kinase activity is regulated by phosphorylation state as well as association with a cyclin subunit and a CDK inhibitor. Inhibitory phosphorylation occurs on Thr14 and Tyr15 (1). Inhibition of CDK2-cyclin complexes can also be attributed to association with p27 Kip1 and p21 Waf1/Cip1 (2). Activation of CDK2 complexes requires dephosphorylation of Thr14 and Tyr15 by cdc25 phosphatase and phosphorylation of Thr160 (3), which is mediated by CAK, a complex of CDK7 and cyclin H (4). CDK2/cyclin E kinase activity is important for the G1 to S transition and phosphorylation of the Rb protein. During S-phase, active CDK2/cyclin A complexes predominate and phosphorylate E2F and the active CDK2 complex persists in the nucleus throughout G2 (5).

$303
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Flow Cytometry, Immunoprecipitation, Peptide ELISA (DELFIA), Western Blotting

Background: Cyclin-dependent kinase 2 (p33CDK2) is an important component of the cell cycle machinery. Like p34cdc2, kinase activity is regulated by phosphorylation state as well as association with a cyclin subunit and a CDK inhibitor. Inhibitory phosphorylation occurs on Thr14 and Tyr15 (1). Inhibition of CDK2-cyclin complexes can also be attributed to association with p27 Kip1 and p21 Waf1/Cip1 (2). Activation of CDK2 complexes requires dephosphorylation of Thr14 and Tyr15 by cdc25 phosphatase and phosphorylation of Thr160 (3), which is mediated by CAK, a complex of CDK7 and cyclin H (4). CDK2/cyclin E kinase activity is important for the G1 to S transition and phosphorylation of the Rb protein. During S-phase, active CDK2/cyclin A complexes predominate and phosphorylate E2F and the active CDK2 complex persists in the nucleus throughout G2 (5).

$262
3 nmol
300 µl
SignalSilence® CDK2 siRNA I from Cell Signaling Technology (CST) allows the researcher to specifically inhibit CDK2 expression using RNA interference, a method whereby gene expression can be selectively silenced through the delivery of double stranded RNA molecules into the cell. All SignalSilence® siRNA products from CST are rigorously tested in-house and have been shown to reduce target protein expression by western analysis.
REACTIVITY
Human

Background: Cyclin-dependent kinase 2 (p33CDK2) is an important component of the cell cycle machinery. Like p34cdc2, kinase activity is regulated by phosphorylation state as well as association with a cyclin subunit and a CDK inhibitor. Inhibitory phosphorylation occurs on Thr14 and Tyr15 (1). Inhibition of CDK2-cyclin complexes can also be attributed to association with p27 Kip1 and p21 Waf1/Cip1 (2). Activation of CDK2 complexes requires dephosphorylation of Thr14 and Tyr15 by cdc25 phosphatase and phosphorylation of Thr160 (3), which is mediated by CAK, a complex of CDK7 and cyclin H (4). CDK2/cyclin E kinase activity is important for the G1 to S transition and phosphorylation of the Rb protein. During S-phase, active CDK2/cyclin A complexes predominate and phosphorylate E2F and the active CDK2 complex persists in the nucleus throughout G2 (5).

$260
100 µl
APPLICATIONS
REACTIVITY
Human, Mouse, Rat

Application Methods: Immunoprecipitation, Western Blotting

Background: RPA70 (HSSB, REPA1, RF-A, RP-A, p70) is a component of a heterotrimeric complex, composed of 70, 32/30 and 14 kDa subunits, collectively known as RPA. RPA is a single stranded DNA binding protein, whose DNA binding activity is believed to reside entirely in the 70 kDa subunit. The complex is required for almost all aspects of cellular DNA metabolism such as DNA replication (1-3), recombination, cell cycle and DNA damage checkpoints, and all major types of DNA repair including nucleotide excision, base excision, mismatch and double-strand break repairs (4-7). In response to genotoxic stress in eukaryotic cells, RPA has been shown to associate with the Rad9/Rad1/Hus1 (9-1-1) checkpoint complex (8). RPA is hyperphosphorylated upon DNA damage or replication stress by checkpoint kinases including ataxia telangiectasia mutated (ATM), ATM and Rad3-related (ATR), and DNA-dependent protein kinase (DNA-PK) (9-11). Phosphorylation of RPA32 occurs at serines 4, 8 and 33 (11). Hyperphosphorylation may alter RPA-DNA and RPA-protein interactions. In addition to the checkpoint partners, RPA interacts with a wide variety of protein partners, including proteins required for normal replication such as RCF, PCNA and Pol α, and also proteins involved in SV40 replication, such as DNA polymerase I and SV40 large T antigen (10,12).

$303
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Flow Cytometry, Immunofluorescence (Immunocytochemistry), Western Blotting

Background: RPA70 (HSSB, REPA1, RF-A, RP-A, p70) is a component of a heterotrimeric complex, composed of 70, 32/30 and 14 kDa subunits, collectively known as RPA. RPA is a single stranded DNA binding protein, whose DNA binding activity is believed to reside entirely in the 70 kDa subunit. The complex is required for almost all aspects of cellular DNA metabolism such as DNA replication (1-3), recombination, cell cycle and DNA damage checkpoints, and all major types of DNA repair including nucleotide excision, base excision, mismatch and double-strand break repairs (4-7). In response to genotoxic stress in eukaryotic cells, RPA has been shown to associate with the Rad9/Rad1/Hus1 (9-1-1) checkpoint complex (8). RPA is hyperphosphorylated upon DNA damage or replication stress by checkpoint kinases including ataxia telangiectasia mutated (ATM), ATM and Rad3-related (ATR), and DNA-dependent protein kinase (DNA-PK) (9-11). Phosphorylation of RPA32 occurs at serines 4, 8 and 33 (11). Hyperphosphorylation may alter RPA-DNA and RPA-protein interactions. In addition to the checkpoint partners, RPA interacts with a wide variety of protein partners, including proteins required for normal replication such as RCF, PCNA and Pol α, and also proteins involved in SV40 replication, such as DNA polymerase I and SV40 large T antigen (10,12).

$122
20 µl
$293
100 µl
APPLICATIONS
REACTIVITY
Human

Application Methods: Immunofluorescence (Immunocytochemistry), Immunohistochemistry (Paraffin), Immunoprecipitation, Western Blotting

Background: RPA70 (HSSB, REPA1, RF-A, RP-A, p70) is a component of a heterotrimeric complex, composed of 70, 32/30 and 14 kDa subunits, collectively known as RPA. RPA is a single stranded DNA binding protein, whose DNA binding activity is believed to reside entirely in the 70 kDa subunit. The complex is required for almost all aspects of cellular DNA metabolism such as DNA replication (1-3), recombination, cell cycle and DNA damage checkpoints, and all major types of DNA repair including nucleotide excision, base excision, mismatch and double-strand break repairs (4-7). In response to genotoxic stress in eukaryotic cells, RPA has been shown to associate with the Rad9/Rad1/Hus1 (9-1-1) checkpoint complex (8). RPA is hyperphosphorylated upon DNA damage or replication stress by checkpoint kinases including ataxia telangiectasia mutated (ATM), ATM and Rad3-related (ATR), and DNA-dependent protein kinase (DNA-PK) (9-11). Phosphorylation of RPA32 occurs at serines 4, 8 and 33 (11). Hyperphosphorylation may alter RPA-DNA and RPA-protein interactions. In addition to the checkpoint partners, RPA interacts with a wide variety of protein partners, including proteins required for normal replication such as RCF, PCNA and Pol α, and also proteins involved in SV40 replication, such as DNA polymerase I and SV40 large T antigen (10,12).