Related Experiment Video
Updated: Aug 18, 2026

Detection and Visualization of DNA Damage-induced Protein Complexes in Suspension Cell Cultures Using the Proximity Ligation Assay
Published on: June 9, 2017
Involvement of protein kinase PKN1 in G2/M delay caused by arsenite
Takayuki Isagawa1, Mikiko Takahashi, Tomohisa Kato
1Graduate School of Science and Technology, Kobe University, Japan.
Abstract:
PKN1 is a serine/threonine protein kinase that has been reported to mediate cellular response to stress. We show here that in response to arsenite exposure, PKN1 kinase activity was stimulated, which was associated with increased binding of PKN1 to Cdc25C and delayed mitotic entry. A role for PKN1 in mediating arsenite-induced G(2)/M delay was supported by the finding that expression of a constitutively active form of PKN1 (PKN1AF3) in HeLa cells delayed the mitotic entry of cell cycle. Further experiments indicate that PKN1 directly phosphorylated serine 216 (Ser216) in Cdc25C, which then facilitated association between Cdc25C and 14-3-3. Significantly, expression of a phosphorylation mutant of Cdc25C (S216A) partially abrogated the cell-cycle arrest in response to arsenite. Together, our results suggest that PKN1 mediates arsenite-induced delay of the G(2)/M transition by binding to and phoshorylating Cdc25C.
Related Concept Videos
DNA Damage can Stall the Cell Cycle
DNA Damage Can Stall the Cell Cycle
Inhibition of Cdk Activity
Negative Regulator Molecules
PI3K/mTOR/AKT Signaling Pathway
Abnormal Proliferation

