» Articles » PMID: 22692200

Coupling Cellular Localization and Function of Checkpoint Kinase 1 (Chk1) in Checkpoints and Cell Viability

Overview
Journal J Biol Chem
Specialty Biochemistry
Date 2012 Jun 14
PMID 22692200
Citations 28
Authors
Affiliations
Soon will be listed here.
Abstract

Chk1 plays a key role in regulating the replication checkpoint and DNA damage response. Recent evidence suggests that mammalian Chk1 regulates both the nuclear and cytoplasmic checkpoint events. However, mechanisms regulating cellular mobilization of Chk1 were not well understood. Here, we report the identification of regions of human Chk1 that regulate its protein cellular localization and checkpoint function. We demonstrate that the two highly conserved motifs (CM1 and CM2) at the C terminus of Chk1 function as a nuclear export signal and nuclear localization signal, respectively. Mutating five highly conserved residues within these two motifs of Chk1 resulted in its accumulation mainly in the cytoplasm. These cytoplasmic Chk1 mutants were less stable and exhibited significantly reduced phosphorylation by DNA damage treatment, yet they retained, at least partially, checkpoint function. Using an adenovirus-mediated gene targeting technique, we attempted to create an HCT116 cell line in which endogenous Chk1 is mutated so that it is expressed exclusively in the cytoplasm. However, we failed to obtain homozygous mutant cell lines. We found that even the heterozygous mutant cell lines showed cell survival defects accompanied by spontaneous cell death. Together, these results reveal novel regulatory mechanisms that couple protein cellular localization with the checkpoint response and cell viability of Chk1.

Citing Articles

SARS-CoV-2 infection induces DNA damage, through CHK1 degradation and impaired 53BP1 recruitment, and cellular senescence.

Gioia U, Tavella S, Martinez-Orellana P, Cicio G, Colliva A, Ceccon M Nat Cell Biol. 2023; 25(4):550-564.

PMID: 36894671 PMC: 10104783. DOI: 10.1038/s41556-023-01096-x.


In search for biomarkers and potential drug targets for uterine serous endometrial cancer.

Dinoi G, Mariani A, Martinelli E, Ciucci A, Zannoni G, Weaver A J Cancer Res Clin Oncol. 2021; 147(6):1647-1658.

PMID: 33754208 PMC: 8076151. DOI: 10.1007/s00432-021-03566-x.


HDAC6 Regulates Radiosensitivity of Non-Small Cell Lung Cancer by Promoting Degradation of Chk1.

Moses N, Zhang M, Wu J, Hu C, Xiang S, Geng X Cells. 2020; 9(10).

PMID: 33020410 PMC: 7600810. DOI: 10.3390/cells9102237.


Testis transcriptome profiling identified genes involved in spermatogenic arrest of cattleyak.

Wu S, Mipam T, Xu C, Zhao W, Shah M, Yi C PLoS One. 2020; 15(2):e0229503.

PMID: 32092127 PMC: 7039509. DOI: 10.1371/journal.pone.0229503.


Melanoma LAMP-2C Modulates Tumor Growth and Autophagy.

Perez L, Sinn A, Sandusky G, Pollok K, Blum J Front Cell Dev Biol. 2018; 6:101.

PMID: 30211163 PMC: 6123356. DOI: 10.3389/fcell.2018.00101.


References
1.
Kaneko Y, Watanabe N, Morisaki H, Akita H, Fujimoto A, Tominaga K . Cell-cycle-dependent and ATM-independent expression of human Chk1 kinase. Oncogene. 1999; 18(25):3673-81. DOI: 10.1038/sj.onc.1202706. View

2.
Lam M, Liu Q, Elledge S, Rosen J . Chk1 is haploinsufficient for multiple functions critical to tumor suppression. Cancer Cell. 2004; 6(1):45-59. DOI: 10.1016/j.ccr.2004.06.015. View

3.
Scorah J, Dong M, Yates 3rd J, Scott M, Gillespie D, McGowan C . A conserved proliferating cell nuclear antigen-interacting protein sequence in Chk1 is required for checkpoint function. J Biol Chem. 2008; 283(25):17250-9. PMC: 2427339. DOI: 10.1074/jbc.M800369200. View

4.
Jackson S, Bartek J . The DNA-damage response in human biology and disease. Nature. 2009; 461(7267):1071-8. PMC: 2906700. DOI: 10.1038/nature08467. View

5.
Zhang Y, Brognard J, Coughlin C, You Z, Dolled-Filhart M, Aslanian A . The F box protein Fbx6 regulates Chk1 stability and cellular sensitivity to replication stress. Mol Cell. 2009; 35(4):442-53. PMC: 2736145. DOI: 10.1016/j.molcel.2009.06.030. View