Biopolym. Cell. 2019; 35(4):303-312.
Structure and Function of Biopolymers
Generation and characterization of the MCF-7 cell line with a knockout of a p85-S6K1 isoform of the ribosomal protein S6 kinase 1
1Holiar V. V., 1Gotsulyak N. Ya., 1Khoruzhenko A. I., 1Zaiets I. V.
  1. Institute of Molecular Biology and Genetics, NAS of Ukraine
    150, Akademika Zabolotnoho Str., Kyiv, Ukraine, 03143


Aim. To generate the p85-S6K1 knockout MCF-7 breast cancer cell line and to evaluate the effect of p85-S6K1 on cell growth, migration and survival under stress conditions. Methods. CRISPR/Cas9 genome editing, Western blotting, immunofluorescence staining, MTT assay, in vitro scratch assay. Results. We generated two clones of the p85-S6K1 knockout MCF-7 cell line and tested their survival upon hydrogen peroxide treatment as well as the proliferation and migration rates. The generated cell clones display an impaired ability to survive under oxidative stress, exhibit inhibition of cell growth, cell motility and downregulation of rpS6 phosphorylation on Ser235/236/240/244 under cell starvation compared to the control cells. Conclusions. The p85-S6K1 isoform could be involved in modulation of cancer cell behaviour promoting cell growth, migration and survival. The obtained clones can be further used to study the participation of different S6K1 isoforms in the control of cell function.
Keywords: mTOR/S6K1 signaling, CRISPR/Cas9, p85-S6K1 isoform.


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