scholarly journals Characterization of p96h2bk: immunoreaction with an anti-Erk(extracellular-signal-regulated kinase) peptide antibody and activity in Xenopus oocytes and eggs

1998 ◽  
Vol 335 (1) ◽  
pp. 43-50
Author(s):  
Dong-Hua CHEN ◽  
Chin-Tin CHEN ◽  
Yong ZHANG ◽  
Mei-Ann LIU ◽  
Roberto CAMPOS-GONZALEZ ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Cycle Arrest ◽  
Xenopus Oocytes ◽  
Protein Kinase Activity ◽  
Cell Stage ◽  
Extracellular Signal Regulated Kinase ◽  
Oncogenic Ras ◽  
Cycle Arrest ◽  
Extracellular Signal ◽  
M Phase

We have shown previously that oncogenic Ras induces cell cycle arrest in activated Xenopus egg extracts [Pan, Chen and Lin (1994) J. Biol. Chem. 269, 5968–5975]. The cell cycle arrest correlates with the stimulation of a protein kinase activity that phosphorylates histone H2b in vitro (designated p96h2bk) [Chen and Pan (1994) J. Biol. Chem. 269, 28034–28043]. We report here that p96h2bk is likely to be p96ram, a protein of approx. 96 kDa that immunoreacts with a monoclonal antibody (Mk-1) raised against a synthetic peptide derived from a sequence highly conserved in Erk1/Erk2 (where Erk is extracellular-signal-regulated kinase). This is supported by two lines of evidence. First, activation/inactivation of p96h2bk correlates with upward/downward bandshifts of p96ram in polyacrylamide gels. Secondly, both p96h2bk and p96ram can be immunoprecipitated by antibody Mk-1. We also studied the activity of p96h2bk/p96ram in Xenopus oocytes and eggs. p96h2bk/p96ram was inactive in stage 6 oocytes, was active in unfertilized eggs, and became inactive again in eggs after fertilization. Since stage 6 oocytes are at G2-phase of the cell cycle, unfertilized eggs arrest at M-phase and eggs exit M-phase arrest after fertilization, the results thus indicate that p96h2bk/p96ram activity is cell cycle dependent. Moreover, microinjection of oncogenic Ras into fertilized eggs at the one-cell stage arrests the embryos at the two-cell stage, and this induced arrest is correlated with an inappropriate activation of p96h2bk/p96ram. The data are consistent with the concept that inappropriate activation of p96h2bk/p96ram plays a role in the cell cycle arrest induced by oncogenic Ras.

scholarly journals The Extracellular Signal-regulated Kinase–Mitogen-activated Protein Kinase Pathway Phosphorylates and Targets Cdc25A for SCFβ-TrCP-dependent Degradation for Cell Cycle Arrest

2009 ◽  
Vol 20 (8) ◽  
pp. 2186-2195 ◽  
Author(s):  
Michitaka Isoda ◽  
Yoshinori Kanemori ◽  
Nobushige Nakajo ◽  
Sanae Uchida ◽  
Katsumi Yamashita ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Cycle Arrest ◽  
Genotoxic Stress ◽  
Mitogen Activated Protein Kinase ◽  
Erk Pathway ◽  
Erk Activation ◽  
Extracellular Signal Regulated Kinase ◽  
Cycle Arrest ◽  
Erk Phosphorylation ◽  
Extracellular Signal

The extracellular signal-regulated kinase (ERK) pathway is generally mitogenic, but, upon strong activation, it causes cell cycle arrest by a not-yet fully understood mechanism. In response to genotoxic stress, Chk1 hyperphosphorylates Cdc25A, a positive cell cycle regulator, and targets it for Skp1/Cullin1/F-box protein (SCF)β-TrCP ubiquitin ligase-dependent degradation, thereby leading to cell cycle arrest. Here, we show that strong ERK activation can also phosphorylate and target Cdc25A for SCFβ-TrCP-dependent degradation. When strongly activated in Xenopus eggs, the ERK pathway induces prominent phosphorylation and SCFβ-TrCP-dependent degradation of Cdc25A. p90rsk, the kinase downstream of ERK, directly phosphorylates Cdc25A on multiple sites, which, interestingly, overlap with Chk1 phosphorylation sites. Furthermore, ERK itself phosphorylates Cdc25A on multiple sites, a major site of which apparently is phosphorylated by cyclin-dependent kinase (Cdk) in Chk1-induced degradation. p90rsk phosphorylation and ERK phosphorylation contribute, roughly equally and additively, to the degradation of Cdc25A, and such Cdc25A degradation occurs during oocyte maturation in which the endogenous ERK pathway is fully activated. Finally, and importantly, ERK-induced Cdc25A degradation can elicit cell cycle arrest in early embryos. These results suggest that strong ERK activation can target Cdc25A for degradation in a manner similar to, but independent of, Chk1 for cell cycle arrest.

scholarly journals The Antiproliferative Activity of Oxypeucedanin via Induction of G2/M Phase Cell Cycle Arrest and p53-Dependent MDM2/p21 Expression in Human Hepatoma Cells

Molecules ◽  
2020 ◽  
Vol 25 (3) ◽  
pp. 501
Author(s):  
So Hyun Park ◽  
Ji-Young Hong ◽  
Hyen Joo Park ◽  
Sang Kook Lee
Keyword(s):  
Cell Cycle ◽  
Cell Cycle Arrest ◽  
Cancer Cells ◽  
Antiproliferative Activity ◽  
Hepatoma Cells ◽  
Phase Cell ◽  
Human Hepatoma Cells ◽  
Cycle Arrest ◽  
Growth Inhibitory Activity ◽  
M Phase

Oxypeucedanin (OPD), a furocoumarin compound from Angelica dahurica (Umbelliferae), exhibits potential antiproliferative activities in human cancer cells. However, the underlying molecular mechanisms of OPD as an anticancer agent in human hepatocellular cancer cells have not been fully elucidated. Therefore, the present study investigated the antiproliferative effect of OPD in SK-Hep-1 human hepatoma cells. OPD effectively inhibited the growth of SK-Hep-1 cells. Flow cytometric analysis revealed that OPD was able to induce G2/M phase cell cycle arrest in cells. The G2/M phase cell cycle arrest by OPD was associated with the downregulation of the checkpoint proteins cyclin B1, cyclin E, cdc2, and cdc25c, and the up-regulation of p-chk1 (Ser345) expression. The growth-inhibitory activity of OPD against hepatoma cells was found to be p53-dependent. The p53-expressing cells (SK-Hep-1 and HepG2) were sensitive, but p53-null cells (Hep3B) were insensitive to the antiproliferative activity of OPD. OPD also activated the expression of p53, and thus leading to the induction of MDM2 and p21, which indicates that the antiproliferative activity of OPD is in part correlated with the modulation of p53 in cancer cells. In addition, the combination of OPD with gemcitabine showed synergistic growth-inhibitory activity in SK-Hep-1 cells. These findings suggest that the anti-proliferative activity of OPD may be highly associated with the induction of G2/M phase cell cycle arrest and upregulation of the p53/MDM2/p21 axis in SK-HEP-1 hepatoma cells.

N-(3'-acetyl-8-nitro-2,3-dihydro-1H,3'H-spiro[quinoline-4,2'-[1,3,4]thiadiazol]-5'-yl) acetamides Induced Cell death in MCF-7 cells via G2/M Phase Cell Cycle Arrest

2022 ◽  
Author(s):  
Selvaraj Shyamsivappan ◽  
Raju Vivek ◽  
Thangaraj Suresh ◽  
Palanivel Naveen ◽  
Kaviyarasu Adhigaman ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Death ◽  
Cell Cycle Arrest ◽  
Spectroscopic Studies ◽  
Phase Cell ◽  
X Ray ◽  
Cycle Arrest ◽  
M Phase ◽  
Mcf 7

A progression of new N-(3'-acetyl-8-nitro-2,3-dihydro-1H,3'H-spiro[quinoline-4,2'-[1,3,4]thiadiazol]-5'-yl) acetamide derivatives were synthesized from potent 8-nitro quinoline-thiosemicarbazones. The synthesized compounds were characterized by different spectroscopic studies and single X-ray crystallographic studies. The compounds were...

scholarly journals Dual effect of 2-methoxyestradiol on cell cycle events in human osteosarcoma 143B cells.

2002 ◽  
Vol 49 (1) ◽  
pp. 59-65 ◽  
Author(s):  
Justyna Gołebiewska ◽  
Piotr Rozwadowski ◽  
Jan Henryk Spodnik ◽  
Narcyz Knap ◽  
Takashi Wakabayashi ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Cell Cycle Arrest ◽  
Growth Inhibitor ◽  
Cytotoxic Action ◽  
M Cell ◽  
Human Osteosarcoma ◽  
Cycle Arrest ◽  
M Phase ◽  
The Stability

We have demonstrated for the first time that the steroid metabolite, 2-methoxyestradiol (2-ME) is a powerful growth inhibitor of human osteosarcoma 143 B cell line by pleiotropic mechanisms involving cell cycle arrest at two different points and apoptosis. The ability of 2-ME to inhibit cell cycle at the respective points has been found concentration dependent. 1 microM 2-ME inhibited cell cycle at G1 phase while 10 microM 2-ME caused G2/M cell cycle arrest. As a natural estrogen metabolite 2-ME is expected to perturb the stability of microtubules (MT) in vivo analogously to Taxol--the MT binding anticancer agent. Contrary to 2-ME, Taxol induced accumulation of osteosarcoma cells in G2/M phase of cell cycle only. The presented data strongly suggest two different mechanisms of cytotoxic action of 2-ME at the level of a single cell.

Sign in / Sign up

Export Citation Format

Share Document