scholarly journals Cell Cycle-dependent Phosphorylation of Human DNA Ligase I at the Cyclin-dependent Kinase Sites

2003 ◽  
Vol 278 (39) ◽  
pp. 37761-37767 ◽  
Author(s):  
Giovanni Ferrari ◽  
Rossella Rossi ◽  
Daniele Arosio ◽  
Alessandro Vindigni ◽  
Giuseppe Biamonti ◽  
...  
1998 ◽  
Vol 273 (32) ◽  
pp. 20540-20550 ◽  
Author(s):  
Emilios K. Dimitriadis ◽  
Rajendra Prasad ◽  
Mary K. Vaske ◽  
Ling Chen ◽  
Alan E. Tomkinson ◽  
...  

2014 ◽  
Vol 25 (15) ◽  
pp. 2250-2259 ◽  
Author(s):  
Nicole Rachfall ◽  
Alyssa E. Johnson ◽  
Sapna Mehta ◽  
Jun-Song Chen ◽  
Kathleen L. Gould

In Schizosaccharomyces pombe, late mitotic events are coordinated with cytokinesis by the septation initiation network (SIN), an essential spindle pole body (SPB)–associated kinase cascade, which controls the formation, maintenance, and constriction of the cytokinetic ring. It is not fully understood how SIN initiation is temporally regulated, but it depends on the activation of the GTPase Spg1, which is inhibited during interphase by the essential bipartite GTPase-activating protein Byr4-Cdc16. Cells are particularly sensitive to the modulation of Byr4, which undergoes cell cycle–dependent phosphorylation presumed to regulate its function. Polo-like kinase, which promotes SIN activation, is partially responsible for Byr4 phosphorylation. Here we show that Byr4 is also controlled by cyclin-dependent kinase (Cdk1)–mediated phosphorylation. A Cdk1 nonphosphorylatable Byr4 phosphomutant displays severe cell division defects, including the formation of elongated, multinucleate cells, failure to maintain the cytokinetic ring, and compromised SPB association of the SIN kinase Cdc7. Our analyses show that Cdk1-mediated phosphoregulation of Byr4 facilitates complete removal of Byr4 from metaphase SPBs in concert with Plo1, revealing an unexpected role for Cdk1 in promoting cytokinesis through activation of the SIN pathway.


2009 ◽  
Vol 38 (1) ◽  
pp. 177-186 ◽  
Author(s):  
Junko Sugatani ◽  
Makoto Osabe ◽  
Masatoshi Kurosawa ◽  
Naomi Kitamura ◽  
Akira Ikari ◽  
...  

2018 ◽  
Vol 8 (1) ◽  
Author(s):  
Sara Ovejero ◽  
Patricia Ayala ◽  
Marcos Malumbres ◽  
Felipe X. Pimentel-Muiños ◽  
Avelino Bueno ◽  
...  

1995 ◽  
Vol 23 (6) ◽  
pp. 962-966 ◽  
Author(s):  
Alessandra Montecucco ◽  
Elena Savini ◽  
Giuseppe Biamonti ◽  
Miria Stefanini ◽  
Federico Focher ◽  
...  
Keyword(s):  

Nature ◽  
2004 ◽  
Vol 432 (7016) ◽  
pp. 473-478 ◽  
Author(s):  
John M. Pascal ◽  
Patrick J. O'Brien ◽  
Alan E. Tomkinson ◽  
Tom Ellenberger
Keyword(s):  

1999 ◽  
Vol 354 (1389) ◽  
pp. 1551-1557 ◽  
Author(s):  
Takashi Toda ◽  
Itziar Ochotorena ◽  
Kin-ichiro Kominami

The SCF complex (Skp1-Cullin-1-F-box) and the APC/cyclosome (anaphase-promoting complex) are two ubiquitin ligases that play a crucial role in eukaryotic cell cycle control. In fission yeast F-box/WD-repeat proteins Pop1 and Pop2, components of SCF are required for cell-cycle-dependent degradation of the cyclin-dependent kinase (CDK) inhibitor Rum1 and the S-phase regulator Cdc18. Accumulation of these proteins in pop1 and pop2 mutants leads to re-replication and defects in sexual differentiation. Despite structural and functional similarities, Pop1 and Pop2 are not redundant homologues. Instead, these two proteins form heterodimers as well as homodimers, such that three distinct complexes, namely SCF Pop1/Pop1 , SCF Pop1/Pop2 and SCF Pop2/Pop2 , appear to exist in the cell. The APC/cyclosome is responsible for inactivation of CDK/cyclins through the degradation of B-type cyclins. We have identified two novel components or regulators of this complex, called Apc10 and Ste9, which are evolutionarily highly conserved. Apc10 (and Ste9), together with Rum1, are required for the establishment of and progression through the G1 phase in fission yeast. We propose that dual downregulation of CDK, one via the APC/cyclosome and the other via the CDK inhibitor, is a universal mechanism that is used to arrest the cell cycle at G1.


1996 ◽  
Vol 16 (12) ◽  
pp. 6965-6976 ◽  
Author(s):  
E J Smith ◽  
G Leone ◽  
J DeGregori ◽  
L Jakoi ◽  
J R Nevins

Previous studies have demonstrated cell cycle-dependent specificities in the interactions of E2F proteins with Rb family members. We now show that the formation of an E2F-p130 complex is unique to cells in a quiescent, G0 state. The E2F-p130 complex does not reform when cells reenter a proliferative state and cycle through G1. The presence of an E2F-p130 complex in quiescent cells coincides with the E2F-mediated repression of transcription of the E2F1 gene, and we show that the E2F sites in the E2F1 promoter are important as cells enter quiescence but play no apparent role in cycling cells. In addition, the decay of the E2F-p130 complex as cells reenter the cell cycle requires the action of G1 cyclin-dependent kinase activity. We conclude that the accumulation of the E2F-p130 complex in quiescent cells provides a negative control of certain key target genes and defines a functional distinction between these G0 cells and cells that exist transiently in G1.


1996 ◽  
Vol 314 (3) ◽  
pp. 993-1000 ◽  
Author(s):  
Ghee T. TAN ◽  
Sangkook LEE ◽  
Ik-Soo LEE ◽  
Jingwen CHEN ◽  
Pete LEITNER ◽  
...  

Enzymic activity mediated by recombinant human DNA ligase I (hLI), in conjunction with tannin removal procedures, has been applied to a natural-product screen involving ~1000 plant extracts and various pure compounds. The primary hLI activity assay involved the measurement of the amount of radiolabelled phosphate in a synthetic nucleic acid hybrid that becomes resistant to alkaline phosphatase as a result of ligation. A bioactivity-guided fractionation scheme resulted in the isolation of ursolic [IC50 = 100 μg/ml (216 μM)] and oleanolic [IC50 = 100 μg/ml (216 μM)] acids from Tricalysia niamniamensis Hiern (Rubiaceae), which demonstrated similar DNA ligase inhibition profiles to other triterpenes such as aleuritolic acid. Protolichesterinic acid [IC50 = 6 μg/ml (20 μM)], swertifrancheside [IC50 = 8 μg/ml (11 μM)] and fulvoplumierin [IC50 = 87 μg/ml (357 μM)] represent three additional natural-product structural classes that inhibit hLI. Fagaronine chloride [IC50 = 10 μg/ml (27 μM)] and certain flavonoids are also among the pure natural products that were found to disrupt the activity of the enzyme, consistent with their nucleic acid intercalative properties. Further analyses revealed that some of the hLI-inhibitory compounds interfered with the initial adenylation step of the ligation reaction, indicating a direct interaction with the enzyme protein. However, in all cases, this enzyme–inhibitor interaction did not disrupt the DNA relaxation activity mediated by hLI. These results indicate that, although the same enzyme active site may be involved in both enzyme adenylation and DNA relaxation, inhibitors may exert allosteric effects by inducing conformational changes that disrupt only one of these activities. Studies with inhibitors are important for the assignment of specific cellular functions to these enzymes, as well as for their development into clinically useful antitumour agents.


2004 ◽  
Vol 24 (22) ◽  
pp. 10036-10046 ◽  
Author(s):  
Aline Pic-Taylor ◽  
Zoulfia Darieva ◽  
Brian A. Morgan ◽  
Andrew D. Sharrocks

ABSTRACT The forkhead transcription factor Fkh2p acts in a DNA-bound complex with Mcm1p and the coactivator Ndd1p to regulate cell cycle-dependent expression of the CLB2 gene cluster in Saccharomyces cerevisiae. Here, we demonstrate that Fkh2p is a target of cyclin-dependent protein kinases and that phosphorylation of Fkh2p promotes interactions between Fkh2p and the coactivator Ndd1p. These phosphorylation-dependent changes in the Fkh2p-Ndd1p complex play an important role in the cell cycle-regulated expression of the CLB2 cluster. Our data therefore identify an important regulatory target for cyclin-dependent kinases in the cell cycle and further our molecular understanding of the key cell cycle regulatory transcription factor Fkh2p.


Sign in / Sign up

Export Citation Format

Share Document