We report the isolation of UME3, a C‐type cyclin that is required for the full repression of several early meiotic genes (e.g. SPO13) and SSA1, a member of the HSP70 superfamily. Similarly to other cyclin C family members, UME3 mRNA and protein levels remained unchanged throughout the mitotic cell cycle. However, under conditions that induce SSA1 or SPO13 transcription, we demonstrate that Ume3p is subjected to degradation. This destruction is required for normal meiotic gene induction, as a mutation that stabilizes Ume3p resulted in a 2‐fold reduction in SPO13 mRNA accumulation. These findings reveal the first observed regulation of a C‐type cyclin. Moreover, the destruction of Ume3p in response to heat shock or developmental cues represents a new set of regulatory signals by which any cyclin is controlled. We identified three cis‐acting domains (PEST‐rich, RXXL and the cyclin box) that contribute to the destruction of Ume3p during heat shock. In cultures exposed to heat shock, Ume3p ...
Cyclin A2 activates the cyclin-dependent kinases Cdk1 and Cdk2 and is expressed at elevated levels from S phase until early mitosis. We found that mutant mice that cannot elevate cyclin A2 are chromosomally unstable and tumor-prone. Underlying the chromosomal instability is a failure to up-regulate the meiotic recombination 11 (Mre11) nuclease in S phase, which leads to impaired resolution of stalled replication forks, insufficient repair of double-stranded DNA breaks, and improper segregation of sister chromosomes. Unexpectedly, cyclin A2 controlled Mre11 abundance through a C-terminal RNA binding domain that selectively and directly binds Mre11 transcripts to mediate polysome loading and translation. These data reveal cyclin A2 as a mechanistically diverse regulator of DNA replication combining multifaceted kinase-dependent functions with a kinase-independent, RNA binding-dependent role that ensures adequate repair of common replication errors. ...
Cyclin F兔多克隆抗体(ab123601)可与人样本反应并经WB实验严格验证。中国75%以上现货,所有产品均提供质保服务,可通过电话、电邮或微信获得本地专属技术支持。
マウス・モノクローナル抗体 ab38 交差種: Ms,Rat,Hu 適用: WB,IP,IHC-P,IHC-Fr,Flow Cyt…Cyclin A2抗体一覧…画像、プロトコール、文献などWeb上の情報が満載のアブカムの Antibody…
The cyclin E oncogene activates CDK2 to drive cells from G1 to S phase of the cell cycle to commence DNA replication. It coordinates essential cellular functions with the cell cycle including histone biogenesis, splicing, centrosome duplication and origin firing for DNA replication. The two E-cyclins, E1 and E2, are assumed to act interchangeably in these functions. However recent reports have identified unique functions for cyclins E1 and E2 in different tissues, and particularly in breast cancer. Cyclins E1 and E2 localise to distinct foci in breast cancer cells as well as co-localising within the cell. Both E-cyclins are found in complex with CDK2, at centrosomes and with the splicing machinery in nuclear speckles. However cyclin E2 uniquely co-localises with NPAT, the main activator of cell-cycle regulated histone transcription. Increased cyclin E2, but not cyclin E1, expression is associated with high expression of replication-dependent histones in breast cancers. The preferential localisation of
Cyclin E is one of the key regulators of the G(1)/S transition in the cell cycle. Overexpression of cyclin E has been observed in several malignancies and is associated with high proliferation, aberrant expression of other cell cycle regulators and chromosomal instability in vitro. To explore potential associations between cyclin E deregulation and inactivation of the p53 tumor suppressor gene in human breast cancer, we investigated the immunohistochemical expression of cyclin E in paraffin embedded breast cancers from 270 women with known p53 status by cDNA based sequencing of the p53 gene. The breast cancers were divided into three subgroups according to the percentage of cyclin E-positive cells. One hundred and seventy-one patients (63%) had low cyclin E, 72 (27%) medium and 27 (10%) had high cyclin E content. Fifty-six percent (15/27) of the breast cancers with high cyclin E had p53 gene mutations, compared with 14% (24/171) of those with low cyclin E content (P , 0.0001). In p53 mutated ...
Breast cancer is one of the most common malignancies in women. Due to early detection and the use of screening programs approximately 60% of all new cases lack lymph node involvement. Today, a substantial proportion of these women will be offered adjuvant systemic chemotherapy. However, better proliferation markers are needed to predict patient outcome and to avoid overtreatment. Cyclin A, cyclin E and Ki-67 are all markers for proliferation and involved in the regulation of the cell cycle. Overexpression has been associated with disease recurrence in several studies, but the results have not been consistent. However, none of these studies has investigated aberrant expression of cyclin E (the expression of cyclin E during phases of the cell cycle other than late G1 and early S-phase). Studies have shown that aberrant cyclin E might provide additional prognostic information compared to cyclin E alone.. The aims of this thesis were 1.to investigate the prognostic value of cyclin A, cyclin E and ...
MEF, a recently identified member of the E74 family of ETS-related transcription factors, is a strong transcriptional activator of cytokine gene expression. Using a green fluorescent protein gene reporter plasmid regulated by an MEF-responsive promot
The mammalian A-type cyclin family consists of two members, cyclin A1 (encoded by Ccna1) and cyclin A2 (encoded by Ccna2). Cyclin A2 promotes both G1/S and G2/M transitions, and targeted deletion of Ccna2 in mouse is embryonic lethal. Cyclin A1 is expressed in mice exclusively in the germ cell lineage and is expressed in humans at highest levels in the testis and certain myeloid leukemia cells. To investigate the role of cyclin A1 and possible redundancy among the cyclins in vivo, mice bearing a null mutation of Ccna1 were generated. Ccna1-/- males are sterile due to a block of spermatogenesis before the first meiotic division, whereas females are normal. Meiosis arrest in Ccna1-/- males is associated with increased germ cell apoptosis, desynapsis abnormalities and reduction of Cdc2 kinase activation at the end of meiotic prophase. Cyclin A1 is therefore essential for spermatocyte passage into the first meiotic division in male mice, a function that cannot be complemented by the concurrently ...
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... , Authors: Immacolata Vocca, Gianmarco Muzi, Francesca Pentimalli, Antonio Giordano. Published in: Atlas Genet Cytogenet Oncol Haematol.
An Intron-Retaining Splice Variant of Human Cyclin A2, Expressed in Adult Differentiated Tissues, Induces a G1-S Cell Cycle Arrest In Vitro. . Biblioteca virtual para leer y descargar libros, documentos, trabajos y tesis universitarias en PDF. Material universiario, documentación y tareas realizadas por universitarios en nuestra biblioteca. Para descargar gratis y para leer online.
References for Abcams Recombinant Human Cyclin E1 protein (ab119719). Please let us know if you have used this product in your publication
Buy our Recombinant Human Cyclin H protein. Ab39435 is a full length protein produced in Escherichia coli and has been validated in WB, ELISA. Abcam provides…
Whereas many components regulating the progression from S phase through G2 phase into mitosis have been identified, the mechanism by which these components control this critical cell cycle progression is still not fully elucidated. Cyclin A/Cdk2 has
Amino acids M1 - K726 (end) of human Cyclin T1. Residue M232 of the fusion protein is equivalent to M11 of the native enzyme. The GST tag is located at residues 1 - 220 ...
TY - JOUR. T1 - Altered p27Kip1 phosphorylation, localization, and function in human epithelial cells resistant to transforming growth factor β-mediated G1 arrest. AU - Ciarallo, Sandra. AU - Subramaniam, Venkateswaran. AU - Hung, Wesley. AU - Lee, Jin Hwa. AU - Kotchetkov, Rouslan. AU - Sandhu, Charanjit. AU - Milic, Andrea. AU - Slingerland, Joyce M. PY - 2002/5/6. Y1 - 2002/5/6. N2 - p27Kip1 is an important effector of G1 arrest by transforming growth factor β(TGF-β). Investigations in a human mammary epithelial cell (HMEC) model, including cells that are sensitive (184s) and resistant (184A1L5R) to G1 arrest by TGF-β, revealed aberrant p27 regulation in the resistant cells. Cyclin El-cyclin-dependent kinase 2 (cdk2) and cyclin A-cdk2 activities were increased, and p27-associated kinase activity was detected in 184A1L5R cells. p27 from 184A1L5R cells was localized to both nucleus and cytoplasm, showed an altered profile of phosphoisoforms, and had a reduced ability to bind and inhibit ...
Mouse Monoclonal Anti-Cyclin D1 Antibody (DCS-6). G1-Cyclin & Mantle Cell Marker. Validated: WB, ELISA, Flow, ICC/IF, IHC-Fr, IHC-P, IP, PAGE. Tested Reactivity: Human, Mouse, Rat, and more. 100% Guaranteed.
Cyclin T1 Antibody 20992-1-AP has been identified with WB, ELISA. 20992-1-AP detected 87 kDa band in K-562 cells with 1:200-1:1000 dilution...
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HIV replication in macrophages contributes to the latent viral reservoirs, which are considered the main barrier to HIV eradication. Few cellular factors that facilitate HIV replication in latently infected cells are known. We previously identified cyclin L2 as a critical factor required by HIV-1 and found that depletion of cyclin L2 attenuates HIV-1 replication in macrophages. Here we demonstrate that cyclin L2 promotes HIV-1 replication through interactions with the dual-specificity tyrosine phosphorylation-regulated kinase 1A (DYRK1A). Cyclin L2 and DYRK1A were colocalized in the nucleus and were found together in immunoprecipitation experiments. Knockdown or inhibition of DYRK1A increased HIV-1 replication in macrophages, while depletion of cyclin L2 decreased HIV-1 replication. Furthermore, depletion of DYRK1A increased expression levels of cyclin L2. DYRK1A is a proline-directed kinase that phosphorylates cyclin L2 at serine residues. Mutations of cyclin L2 at serine residues preceding ...
Although mutations that activate the Hedgehog (Hh) signalling pathway have been linked to several types of cancer, the molecular and cellular basis of Hhs ability to induce tumour formation is not well understood. We identified a mutation in patched (ptc), an inhibitor of Hh signalling, in a genetic screen for regulators of the Retinoblastoma (Rb) pathway in Drosophila. Here we show that Hh signalling promotes transcription of Cyclin E and Cyclin D, two inhibitors of Rb, and principal regulators of the cell cycle during development in Drosophila. Upregulation of Cyclin E expression, accomplished through binding of Cubitus interruptus (Ci) to the Cyclin E promoter, mediates the ability of Hh to induce DNA replication. Upregulation of Cyclin D expression by Hh mediates the distinct ability of Hh to promote cellular growth. The discovery of a direct connection between Hh signalling and principal cell-cycle regulators provides insight into the mechanism by which deregulated Hh signalling promotes ...
FIG.9. Effects of UV stimulation on cyclin D1 and p52. (A) UV treatment down regulates cyclin D1 protein levels. U-2 OS cells were treated with 40-J/m2 UV radiation for the indicated times. Whole-cell lysates were prepared and immunoblotted for cyclin D1 and a β-actin control as indicated. (B) UV treatment inhibits the cyclin D1 promoter in a manner dependent upon the proximal κB element. One and a half micrograms of each of the cyclin D1 (−66) and cyclin D1 (−66 mut) luciferase reporter plasmids were transfected into U-2 OS cells. Cells were treated with 40-J/m2 UV radiation for 6 h as indicated. Results are expressed as change in activation or repression (n-fold) relative to levels seen in the relevant untreated cell controls. luc, luciferase. (C) UV treatment induces Ser-15 phosphorylated endogenous p53 and down regulates Bcl-3 levels. U-2 OS cells were treated with 40-J/m2 UV radiation for the indicated times. Nuclear protein extracts were prepared and immunoblotted for p53, ...
Looking for online definition of Cyclin F in the Medical Dictionary? Cyclin F explanation free. What is Cyclin F? Meaning of Cyclin F medical term. What does Cyclin F mean?
The protein encoded by the Bcl-1 oncogene, known as cyclin D1, belongs to the highly conserved family of cyclin-dependent kinase (CDK) regulators. It is also known as CCND1, B-cell lymphoma 1 protein (BCL1), parathyroid adenomatosis 1 (PRAD1), B-cell CLL/lymphoma 1, G1/S-specific cyclin-D1, D11S287E, and U21B31. Different cyclins exhibit distinct expression and degradation patterns that contribute to the coordination of the cell cycle during mitosis. Cyclin D1 interacts with CDK4 and CDK6, whose activity is required for the cell cycle G1/S transition. Cyclin D1 also interacts with tumor suppressor protein Rb. Mutations in the Bcl-1 gene are associated with a variety of cancers, including esophageal, breast, and bladder cancer, as well as a variety of B-cell-related leukemias and lymphomas.. ...
Our experiments demonstrate the existence of a complex containing both cyclin E and several components of the U2 snRNP in vivo, in particular SAP 155, SAP 145, and SAP 114. We were able to detect the association between both cyclin E and SAP 155, as well as cdk2 and SAP 155, through either of the components in cellular lysates. The cyclin E-SAP 155 association can also be shown in the yeast two-hybrid system and can be reconstituted in vitro by using recombinant components. Furthermore, we found that cyclin E-specific antibodies were able to precipitate U1 and U2 snRNAs, as well as the pre-mRNA substrate from preassembled spliceosomes.. We find that one component of U2 snRNP, SAP 155, serves as an excellent substrate for cyclin E-cdk2 both in the U2/E/k2 complex precipitated from cells and as a recombinant protein in vitro. Phosphorylation of SAP 155 in the U2/E/k2 complex can be inhibited by preincubation of these complexes with p21, a known cyclin-kinase inhibitor. Taken together, these data ...
Cyclin A2 (encoded by CCNA2) is responsible for activating the cyclin-dependent kinases CDK1 and CDK2 to induce S-phase chromosome duplication and initiate mitosis. As both underexpression and overexpression of cyclin A2 have been linked to poor outcome in tumors, the role of cyclin A2 in tumor progression is unclear. Because complete loss of cyclin A2 is embryonically lethal, Kanakkanthara and colleagues developed a hypomorphic Ccna2 allele (Ccna2H) with reduced expression of cyclin A2 to better understand its role in tumorigenesis. Ccna2−/H mice had a marked reduction in cyclin A2 protein in tissues with a high mitotic index but relatively normal levels in tissues with less actively dividing cells. Ccna2−/H mice were more susceptible to spontaneous and carcinogen-induced tumors than Ccna2+/+ mice, indicating that cyclin A2 insufficiency promotes malignant transformation. Mouse embryonic fibroblasts (MEF) from Ccna2−/H mice exhibited increased aneuploidy due to chromosome segregation ...
TY - JOUR. T1 - Systematic determination of human cyclin dependent kinase (CDK)-9 interactome identifies novel functions in RNA splicing mediated by the DEAD Box (DDX)-5/17 RNA helicases. AU - Yang, Jun. AU - Zhao, Yingxin. AU - Kalita, Mridul. AU - Li, Xueling. AU - Jamaluddin, Mohammad. AU - Tian, Bing. AU - Edeh, Chukwudi B.. AU - Wiktorowicz, John E.. AU - Kudlicki, Andrzej. AU - Brasier, Allan R.. PY - 2015/10/1. Y1 - 2015/10/1. N2 - Inducible transcriptional elongation is a rapid, stereotypic mechanism for activating immediate early immune defense genes by the epithelium in response to viral pathogens. Here, the recruitment of a multifunctional complex containing the cyclin dependent kinase 9 (CDK9) triggers the process of transcriptional elongation activating resting RNA polymerase engaged with innate immune response (IIR) genes. To identify additional functional activity of the CDK9 complex, we conducted immunoprecipitation (IP) enrichment-stable isotope labeling LC-MS/MS of the CDK9 ...
The smooth progression of the eukaryotic cell cycle relies on the periodic activation of members of a family of cell cycle kinases by regulatory proteins called cyclins. Outside of the cell cycle, cyclin homologs play important roles in regulating the assembly of transcription complexes; distant structural relatives of the conserved cyclin core or box can also function as general transcription factors (like TFIIB) or survive embedded in the chain of the tumor suppressor, retinoblastoma protein. The present work attempts the prediction of the canonical secondary, supersecondary, and tertiary fold of the minimal cyclin box domain using a combination of techniques that make use of the evolutionary information captured in a multiple alignment of homolog sequences. A tandem set of closely packed, helical modules are predicted to form the cyclin box domain.
In humans, there are two A-type cyclins - an embryonic-specific cyclin A1 and a somatic cyclin A2. Cyclin A1 is only expressed in meiosis and very early embryos, whereas cyclin A2 is present in proliferating somatic cells
The alternatively spliced cyclin D1b variant of the CCND1 gene has been proposed to have higher oncogenic potential than cyclin D1a (8, 9). In breast cancer, aberrant cyclin D1b expression confers resistance to therapeutic treatment (30) and is associated with poor prognosis in patients (31). Cyclin D1b was also recently shown to enhance cell invasiveness and anchorage-independent growth of bladder cancer cells (32), and this isoform has been detected in various other cancer types (8, 28, 33). In PCa, changes in the cyclin D1b/cyclin D1a ratio are of particular relevance. Indeed, whereas both isoforms support cell cycle progression, they behave differently in the interaction with the AR pathway. Cyclin D1a was reported to associate with AR and to negatively regulate its transcriptional activity, thereby representing a brake for uncontrolled proliferation of PCa cells (6). By contrast, this negative feedback function is lacking in cyclin D1b (11), and its expression positively correlated with PCa ...
2494 Cyclin I (CCNI) is a member of the recently described inhibitory class of cyclin proteins. The other members of this class, cyclins G1 and G2, have been implicated in the induction of cell cycle arrest. Cyclin I is widely expressed in terminally differentiated tissues, but its function remains to be determined. We previously identified cyclin I as antigenic in a mouse model of ovarian cancer. Here, we examined expression of the human cyclin I gene in normal tissues, in tumor cell lines, and in primary human ovarian tumors. By Northern blot analysis, cyclin I was expressed at moderate to high levels in all normal tissues examined, including normal ovary. In contrast, cyclin I mRNA was dramatically reduced in nine of twenty-five ovarian tumor samples examined. These studies were confirmed and extended using quantitative real-time PCR analysis. More than half of the tumors evaluated had very low levels of cyclin I mRNA compared to the expression levels in normal ovarian tissue and other normal ...
购买经敲除验证的重组Cyclin D1兔单克隆抗体[EP272Y](ab40754),Cyclin D1抗体经WB,IP验证,可与人,小鼠,大鼠样本反应。8篇文献引用,4个独立用户反馈。
Cyclin E is an important regulator of cell cycle progression. Various studies examined the relationship between cyclin E overexpression with the clinical outcome in patients with breast cancer but yie
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Although most efforts to develop antagonists of CDK function have focused on identifying and optimizing ATP-competitive CDK inhibitors, a number of studies have been published in which new, creative strategies have been used. Most of these approaches focus on CDK2 inhibition. This is in part due to the fact that X-ray crystal structures of CDK2 and the cyclin A/CDK2 complex have been available longer than similar data for other CDK and cyclin/CDK complexes. A crystal structure of cyclin A/CDK2 in complex with ATP and a substrate peptide (Brown et al., 1999) (Fig. 3A) shows ATP bound in a cleft formed on one side by the GEGTYG nucleotide-binding motif (red- and blue-colored residues). The peptide substrate is bound in a cleft adjacent to the ATP binding site and in close apposition to ATP. Interestingly, binding of the endogenous CDK inhibitor p27 to cyclin A/CDK2 causes large-scale structural changes to the cyclin A/CDK2 complex (Fig. 3B) (Russo et al., 1996). p27 inserts itself into the ATP ...
Cyclin T2 antibody LS-C342834 is an unconjugated mouse monoclonal antibody to human Cyclin T2 (CCNT2 ). Validated for DB and WB.
Cyclin D1 expression is induced by Sox17.(A-B) Immunohistochemistry for cyclin D1 was performed on lung sections from adult CCSPrtTA (A) and CCSPrtTA/tetO-Sox
Plasmid pIS1 Cyclin D2 short UTR from Dr. David Bartels lab contains the insert Cyclin D2 short UTR and is published in Cell. 2009 Aug 21. 138(4):673-84. This plasmid is available through Addgene.
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Amino acids S11 - H267 (end residue is R580) of human Cyclin K. Residue S232 of the fusion protein is equivalent to S11 of the native enzyme. The GST tag is located at residues 1 - 220 ...
Rabbit Polyclonal Anti-Cyclin A1 Antibody. Validated: WB, ELISA, ICC/IF, IHC, IHC-P, IP. Tested Reactivity: Human, Mouse, Rat. 100% Guaranteed.
View mouse Ccndbp1 Chr2:121008403-121016904 with: phenotypes, sequences, polymorphisms, proteins, references, function, expression
CNTD2 - CNTD2 (untagged)-Human cyclin N-terminal domain containing 2 (CNTD2), transcript variant 2 available for purchase from OriGene - Your Gene Company.
1W60: Structural and Biochemical Studies of Human Proliferating Cell Nuclear Antigen Complexes Provide a Rationale for Cyclin Association and Inhibitor Design
TY - JOUR. T1 - Interaction between the pRb2/p130 C-terminal domain and the N-terminal portion of cyclin D3. AU - Bonetto, Francesco. AU - Fanciulli, Maurizio. AU - Battista, Tullio. AU - De Luca, Antonio. AU - Russo, Patrizia. AU - Bruno, Tiziana. AU - De Angelis, Roberta. AU - Di Padova, Monica. AU - Giordano, Antonio. AU - Felsani, Armando. AU - Paggi, Marco C.. PY - 1999/12/15. Y1 - 1999/12/15. N2 - An association between cyclin D3 and the C-terminal domain of pRb2/p130 was demonstrated using the yeast two-hybrid system. Further analysis restricted the epitope responsible for the binding within the 74 N-terminal amino acids of cyclin D3, independent of the LXCXE amino acid motif present in the D-type cyclin N-terminal region. In a coprecipitation assay in T98G cells, a human glioblastoma cell line, the C-terminal domain of pRb2/p130 was able to interact solely with cyclin D3, while the corresponding portion of pRb interacted with either cyclin D3 or cyclin D1. In T98G cells, endogenous ...
The G1 cyclins, cyclin D1 and E, are rate limiting for progression through G1 phase of the cell cycle in breast epithelial cells and are oncogenic when expressed in the mammary epithelium of transgenic mice. These genes are frequently overexpressed in clinical breast cancer where overexpression appears to be associated with specific disease phenotypes, altered responsiveness to therapeutic intervention and patient survival. In order to investigate the functional correlates of cyclin D1 and cyclin E overexpression we employed a panel of normal, immortalized and neoplastic breast epithelial cell lines to examine the relationships between cyclin gene expression, cyclin-CDK complex formation and CDK activity. In agreement with earlier studies cyclin D1 and E expression varied over an approximately tenfold range among the 18 cell lines studied. There was no apparent relationship, however, between cyclin D1 expression and the in vitro activity of its major kinase partner, Cdk4, although MDA-MB-134 cells