• β-TrCP- and Casein Kinase II-Mediated Degradation of Cyclin F Controls Timely Mitotic Progression. (ox.ac.uk)
  • β-TrCP recognizes cyclin F through a non-canonical degron site (TSGXXS) after its phosphorylation by casein kinase II. (ox.ac.uk)
  • This cyclin forms a complex with CDK7 kinase and ring finger protein MAT1. (novusbio.com)
  • This cyclin and its kinase partner are components of TFIIH, as well as RNA polymerase II protein complexes. (novusbio.com)
  • Dysregulation of CDK8 (Cyclin-Dependent Kinase 8) and its regulatory partner CycC (Cyclin C) , two subunits of the conserved Mediator (MED) complex, have been linked to diverse human diseases such as cancer. (sdbonline.org)
  • Recent studies have shown that cyclin-dependent kinase (CDK) inhibitors can have a tremendous impact on cell cycle progression in plants. (uni-bielefeld.de)
  • Destruction of the CDC28/CLB mitotic kinase is not required for the metaphase to anaphase transition in budding yeast. (ox.ac.uk)
  • It is widely assumed that degradation of mitotic cyclins causes a decrease in mitotic cdc2/CDC28 kinase activity and thereby triggers the metaphase to anaphase transition. (ox.ac.uk)
  • Two observations made on the budding yeast Saccharomyces cerevisiae are inconsistent with this scenario: (i) anaphase occurs in the presence of high levels of kinase in cdc15 mutants and (ii) overproduction of a B-type mitotic cyclin causes arrest not in metaphase as previously reported but in telophase. (ox.ac.uk)
  • The activator Cdc20 is then replaced by a second activator, Cdh1, and APC/C Cdh1 promotes complete degradation of M cyclin, followed by polo-like kinase 1, Aurora A, and other substrates, to complete mitosis and cytokinesis and drive progression into G1 [ 1 , 2 ]. (biomedcentral.com)
  • The precise regulation of the levels of cyclin proteins is fundamental to coordinate cell division with checkpoints, avoiding genome instability. (ox.ac.uk)
  • Cyclin A is a member of the cyclin family, a group of proteins that function in regulating progression through the cell cycle. (wikipedia.org)
  • The mechanism, which is based on the synthesis and degradation of three ''master regulator'' proteins (CtrA, GcrA, and DnaA), is converted into a quantitative model, in order to study the temporal dynamics of these and other cell cycle proteins. (ebi.ac.uk)
  • The activity of CDKs is controlled by their binding to coactivator subunits termed Cyclins, as well as by CDK inhibitory proteins termed CKIs. (intechopen.com)
  • The accumulation of both Cyclin and CKI proteins is tightly regulated at the level of transcription. (intechopen.com)
  • In addition, Cyclin and CKI proteins are controlled at the level of their destruction. (intechopen.com)
  • The APC/C is an E3 ubiquitin ligase that drives mitotic progression by promoting timely degradation of key regulatory proteins [ 3 ]. (biomedcentral.com)
  • Cyclin A, along with the other members of the cyclin family, regulates cell cycle progression through physically interacting with cyclin-dependent kinases (CDKs), which thereby activates the enzymatic activity of its CDK partner. (wikipedia.org)
  • Cyclins function as regulators of CDK kinases. (novusbio.com)
  • Progression through the cell cycle is driven by the oscillating activity of Cyclin Dependent Kinases (CDKs). (intechopen.com)
  • These changes are orchestrated by a small number of master regulators, including the cyclin-dependent kinases (Cdks) and the anaphase-promoting complex/cyclosome (APC/C). Each Cdk or APC/C isoform has a large number of substrates, and the substrates of each isoform are modified in a specific order that leads to sequential substrate activation or inactivation. (biomedcentral.com)
  • This event is required to promote mitotic progression and favors the activation of a transcriptional program required for mitosis. (ox.ac.uk)
  • A study in 2008 provided further evidence of cyclin A/CDK2 complex's role in mitosis. (wikipedia.org)
  • These mutants entered mitosis late due to a delayed activation of the cyclin B/CDK1 complex. (wikipedia.org)
  • We introduced autocatalytic transcription of E2F, E2F regulated transcription of cyclin B, Cdc20/Cdh1 mediated E2F degradation, enhanced transcription of mitotic cyclins during late S/early G2 phase, and the sustained synthesis of cyclin B during mitosis. (ebi.ac.uk)
  • The CDK4 activity associated with this cyclin was reported to be necessary for cell cycle progression through G2 phase into mitosis after UV radiation. (creative-biolabs.com)
  • B-type cyclins are rapidly degraded in the transition between metaphase and anaphase and their ubiquitin-mediated proteolysis is necessary for cells to exit mitosis. (bibf1120.com)
  • Here, we used experimental and computational approaches to dissect the quantitative mechanisms underlying the ordered degradation of the substrates of the ubiquitin ligase APC/C Cdc20 , a key regulator of chromosome segregation in mitosis. (biomedcentral.com)
  • Once cyclin B is activated, cyclin A is no longer needed and is subsequently degraded through the ubiquitin pathway. (wikipedia.org)
  • In particular, ubiquitin-mediated degradation is critically important at transition points where it provides directionality and irreversibility to the cell cycle, which is essential for maintaining genome integrity. (intechopen.com)
  • Cyclin A/CDK2 complex was thought to be restricted to the nucleus and thus exclusively involved in S phase progression. (wikipedia.org)
  • Transcription of cyclin A is tightly regulated and synchronized with cell cycle progression. (wikipedia.org)
  • Initiation of transcription of cyclin A is coordinated with passage of the R point, a critical transition point that is required for progression from G1 into S phase. (wikipedia.org)
  • Paradoxically, progression deeper into cell cycle arrest was accompanied by increases in proliferative effectors such as CDKs and cyclins, which can drive cell cycle re-entry by overcoming p21 induction. (bvsalud.org)
  • Cyclin A can regulate multiple cell cycle steps because it associates with, and thereby activates, two distinct CDKs - CDK2 and CDK1. (wikipedia.org)
  • Association of cyclin A with CDK2 is required for passage into S phase while association with CDK1 is required for entry into M phase. (wikipedia.org)
  • In late S phase, cyclin A can also associate with CDK1. (wikipedia.org)
  • Cyclin A remains associated with CDK1 from late S into late G2 phase when it is replaced by cyclin B. Cyclin A/CDK1 is thought to be involved in the activation and stabilization of cyclin B/CDK1 complex. (wikipedia.org)
  • Degradation of cyclin A/CDK1 induces mitotic exit. (wikipedia.org)
  • It is suspected that the presence of cyclin A/CDK2 at the centrosomes may confer a means of regulating the movement of cyclin B/CDK1 to the centrosome and thus the timing of mitotic events. (wikipedia.org)
  • The model was built by integrating and modifying two previously published models such that the model outputs for cyclins A and B fit cyclin expression measurements and the activation of B cyclin/Cdk1 coincided with phosphorylation of histone H3. (ebi.ac.uk)
  • The model depends on Cdh1-regulated cyclin degradation during G1, regulation of B cyclin/Cdk1 activity by cyclin A/Cdk via Wee1, and transcriptional control of the mitotic cyclins that reflects some of the current literature. (ebi.ac.uk)
  • Cdc2 regulation also involves positive feedback4, with active Cdc2-cyclin B stimulating its activator Cdc25 and inactivating its inhibitors Wee1 and Myt1. (sontaglab.org)
  • however, the mechanisms underlying the regulation of cyclin F are poorly understood. (ox.ac.uk)
  • One such regulatory component is cyclin A which plays a role in the regulation of two different cell cycle stages. (wikipedia.org)
  • The degradation of cyclin F mediated by β-TrCP occurs at the G2/M transition. (ox.ac.uk)
  • Depending on which CDK partner cyclin A binds, the cell will continue through the S phase or it will transition from G2 to the M phase. (wikipedia.org)
  • Cyclin A has been shown to play a crucial role in the G2/M transition in Drosophila and Xenopus embryos. (wikipedia.org)
  • This cyclin forms a complex with and functions as a regulatory subunit of CDK4 or CDK6, whose activity is required for cell cycle G1/S transition. (genetex.com)
  • A single cyclin A gene has been identified in Drosophila while Xenopus, mice and humans contain two distinct types of cyclin A: A1, the embryonic-specific form, and A2, the somatic form. (wikipedia.org)
  • Cells were modified so their CDK2 was inhibited and their cyclin A2 gene was knocked out. (wikipedia.org)
  • The protein encoded by this gene belongs to the highly conserved cyclin family, whose members are characterized by a dramatic periodicity in protein abundance through the cell cycle. (novusbio.com)
  • This degradation is mediated by at least two domains indicating the presence of at least two different pathways impinging on ICK1/KRP1 protein stability. (uni-bielefeld.de)
  • Numerical simulations reproduce the main features of wild-type mitotic cycles: patterns of protein accumulation and degradation, lengthening of later cycles, and arrest in interphase 14. (vt.edu)
  • Using a computational model based on multi-step ubiquitination, we then show how changes in the interaction between a single substrate and APC/C Cdc20 can alter the timing of degradation onset relative to APC/C Cdc20 activation, while ensuring a fast degradation rate. (biomedcentral.com)
  • Depending on how APC/C Cdc20 is partitioned among its substrates, competition can have minor or major effects on the degradation of certain substrates. (biomedcentral.com)
  • We show experimentally that increased expression of the early APC/C Cdc20 substrate Clb5 does not delay the degradation of the later substrate securin, arguing against a role for competition with Clb5 in establishing securin degradation timing. (biomedcentral.com)
  • The degradation timing of APC/C Cdc20 substrates depends on the multi-step nature of ubiquitination, differences in substrate-APC/C Cdc20 interactions, and competition among substrates. (biomedcentral.com)
  • Among the diverse signaling outcomes associated with ubiquitination, the most well-established is the targeted degradation of substrates via the proteasome. (intechopen.com)
  • These chains are recognized by the proteasome, leading to substrate degradation [ 11 ]. (biomedcentral.com)
  • Since its initial discovery, homologues of cyclin A have been identified in numerous eukaryotes including Drosophila, Xenopus, mice, and in humans but has not been found in lower eukaryotes like yeast. (wikipedia.org)
  • Xiao (cell department routine) mutants and determined a book mutant (and so are mixed up in degradation of Clb2 and the merchandise of both genes associate using the candida APC. (bibf1120.com)
  • They were shifted to 37°C to prearrest potential G1 and mitotic arrest mutants for 2 h then hydroxyurea was added to 10 mg/ml and cells were incubated at 37°C for an additional 5 h. (bibf1120.com)
  • Cyclin A resides in the nucleus during S phase where it is involved in the initiation and completion of DNA replication. (wikipedia.org)
  • Coupling of microtubule nucleation in the centrosome with mitotic events in the nucleus was lost in the cyclin A knockout/CDK2 inhibited mutant cells. (wikipedia.org)
  • Immunocytochemistry/ Immunofluorescence: Cyclin H Antibody (1B8) [H00000902-M01] - Analysis of monoclonal antibody to CCNH on HeLa cell. (novusbio.com)
  • Immunohistochemistry-Paraffin: Cyclin H Antibody (1B8) [H00000902-M01] - Analysis of monoclonal antibody to CCNH on formalin-fixed paraffin-embedded human testis. (novusbio.com)
  • Western Blot: Cyclin H Antibody (1B8) [H00000902-M01] - CCNH monoclonal antibody (M01), clone 1B8 Analysis of CCNH expression in HeLa. (novusbio.com)
  • Sandwich ELISA: Cyclin H Antibody (1B8) [H00000902-M01] - Detection limit for recombinant GST tagged CCNH is approximately 1ng/ml as a capture antibody. (novusbio.com)
  • WB analysis of HeLa cell lysate using GTX33611 Cyclin D1 antibody [RM241]. (genetex.com)
  • IHC-P analysis of human tonsil tissue using GTX33611 Cyclin D1 antibody [RM241]. (genetex.com)
  • There are currently no references for Cyclin D1 antibody [RM241] (GTX33611) . (genetex.com)
  • Cyclin A was first identified in 1983 in sea urchin embryos. (wikipedia.org)
  • Since the action of cyclin A/CDK2 inhibits that of cyclin E/CDK2, the sequential activation of cyclin E followed by the activation of cyclin A is important and tightly regulated in S phase. (wikipedia.org)
  • The model is consistent with mutations that introduce subtle changes in the number of mitotic cycles before interphase arrest. (vt.edu)
  • the APC then promotes cyclin degradation and resets Cdc2 to its inactive, interphase state. (sontaglab.org)
  • Degradation of maternal transcripts and zygotic genome activation is characterized by striking changes in the transcriptome profiles. (biomedcentral.com)
  • Different cyclins exhibit distinct expression and degradation patterns which contribute to the temporal coordination of each mitotic event. (novusbio.com)
  • Cyclin A binds to the mitotic spindle poles in the centrosome however, the mechanism by which the complex is shuttled to the centrosome is not well understood. (wikipedia.org)
  • This paper examined whether Cdc2 activation is bistable, confirming that the response of Cdc2 to non-degradable cyclin B is temporally abrupt and switchlike, as would be expected if Cdc2 activation were bistable. (sontaglab.org)
  • The interaction between the cyclin box, a region conserved across cyclins, and a region of the CDK, called the PSTAIRE, confers the foundation of the cyclin-CDK complex. (wikipedia.org)
  • As the cell passes from G1 into S phase, cyclin A associates with CDK2, replacing cyclin E. Cyclin E is responsible for initiating the assembly of the pre-replication complex. (wikipedia.org)
  • When the amount of cyclin A/CDK2 complex reaches a threshold level, it terminates the assembly of the pre-replication complex made by cyclin E/CDK2. (wikipedia.org)
  • Localization to the chromocenters is mediated by an N-terminal domain, in addition we find that this domain may be involved in cyclin binding. (uni-bielefeld.de)
  • During these mitotic cycles, there are barely detectable oscillations in the total level of B-type cyclins. (vt.edu)
  • These findings help establish the basic systems-level logic of the mitotic oscillator. (sontaglab.org)
  • New research has since debunked this assumption, shedding light on cyclin A/CDK2 migration to the centrosomes in late G2. (wikipedia.org)
  • Bifurcation analysis of the differential equations reveals the dependence of mitotic oscillations on cycle number, and how this dependence is altered by mutations. (vt.edu)