Regulation of Human Cdc25A Stability by Serine 75 Phosphorylation Is Not Sufficient to Activate a S-phase Checkpoint
نویسندگان
چکیده
منابع مشابه
Phosphorylation at serine 75 is required for UV-mediated degradation of human Cdc25A phosphatase at the S-phase checkpoint.
The human Cdc25A phosphatase plays a pivotal role at the G1/S transition by activating cyclin E and A/Cdk2 complexes through dephosphorylation. In response to ionizing radiation, Cdc25A is phosphorylated by both Chk1 and Chk2 on Ser-123. This in turn leads to ubiquitylation and rapid degradation of Cdc25A by the proteasome resulting in cell cycle arrest. We found that in response to UV irradiat...
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Although it is well established that inheritance of mutations in the Brca1 gene significantly increases the chances of developing breast or ovarian cancers, the mechanisms underlying this specific tumor susceptibility remain to be clarified. It is clear that one of the roles of the Brca1 protein is to facilitate cellular responses to DNA damage. We recently reported that Brca1 function is requi...
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Background and objectives: Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) inhibition results in an increase in apoptosis. It has been demonstrated that NF-κB subunit p65 phosphorylation at the IκB kinase phosphorylation site serine 536 (Ser536) is essential for the NF-κB nuclear translocation and activation. Therefore, NF-κB can be downregulated by suppressing its phosph...
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ژورنال
عنوان ژورنال: Cell Cycle
سال: 2003
ISSN: 1538-4101,1551-4005
DOI: 10.4161/cc.2.5.482