A gemcitabine sensitivity screen identifies a role for NEK9 in the replication stress response.
Nucleic Acids Res
; 42(18): 11517-27, 2014 Oct.
Article
in En
| MEDLINE
| ID: mdl-25217585
ABSTRACT
The Replication Stress Response (RSR) is a signaling network that recognizes challenges to DNA replication and coordinates diverse DNA repair and cell-cycle checkpoint pathways. Gemcitabine is a nucleoside analogue that causes cytotoxicity by inducing DNA replication blocks. Using a synthetic lethal screen of a RNAi library of nuclear enzymes to identify genes that when silenced cause gemcitabine sensitization or resistance in human triple-negative breast cancer cells, we identified NIMA (never in mitosis gene A)-related kinase 9 (NEK9) as a key component of the RSR. NEK9 depletion in cells leads to replication stress hypersensitivity, spontaneous accumulation of DNA damage and RPA70 foci, and an impairment in recovery from replication arrest. NEK9 protein levels also increase in response to replication stress. NEK9 complexes with CHK1, and moreover, NEK9 depletion impairs CHK1 autophosphorylation and kinase activity in response to replication stress. Thus, NEK9 is a critical component of the RSR that promotes CHK1 activity, maintaining genome integrity following challenges to DNA replication.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Stress, Physiological
/
Protein Serine-Threonine Kinases
/
Deoxycytidine
/
DNA Replication
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Antimetabolites, Antineoplastic
Type of study:
Diagnostic_studies
/
Prognostic_studies
Limits:
Female
/
Humans
Language:
En
Journal:
Nucleic Acids Res
Year:
2014
Document type:
Article
Affiliation country:
United States