Functional interplay between the cell cycle and cell phenotypes

Johns Hopkins Physical Sciences - Oncology Center, The Johns Hopkins University, Baltimore, Maryland 21218, USA. .
Integrative Biology (Impact Factor: 3.76). 01/2013; 5(3). DOI: 10.1039/c2ib20246h
Source: PubMed


Cell cycle distribution of adherent cells is typically assessed using flow cytometry, which precludes the measurements of many cell properties and their cycle phase in the same environment. Here we develop and validate a microscopy system to quantitatively analyze the cell-cycle phase of thousands of adherent cells and their associated cell properties simultaneously. This assay demonstrates that population-averaged cell phenotypes can be written as a linear combination of cell-cycle fractions and phase-dependent phenotypes. By perturbing the cell cycle through inhibition of cell-cycle regulators or changing nuclear morphology by depletion of structural proteins, our results reveal that cell cycle regulators and structural proteins can significantly interfere with each other's prima facie functions. This study introduces a high-throughput method to simultaneously measure the cell cycle and phenotypes at single-cell resolution, which reveals a complex functional interplay between the cell cycle and cell phenotypes.

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Available from: Jerry Ssu-Hsien Lee, Jun 11, 2015
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    • "h SINC - GFP ( wild type or AB ) were fixed with methanol , stained with DAPI , and stained for indi - rect immunofluorescence with antibodies against GFP or tubulin as the cytoplasmic marker . Images were segmented and analyzed us - ing hTCP , a Matlab script provided by Jacob Sarnecki and Denis Wirtz ( Johns Hopkins University , Baltimore , MD ; Chen et al . , 2013 ) to measure nuclear circularity . GFP - positive transfectants ( n = 300 SINC - GFP wild type ; n = 218 SINC AB - GFP ) were identified as cells with summed GFP intensities >2 SDs above the mean . Untrans - fected ( GFP - negative ) cells numbered 1199 and 1098 , respectively . Nuclei in AB - GFP – transfected cells were significantly "
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