Optimization of Yeast Cell Cycle Analysis and Morphological Characterization by Multispectral Imaging Flow Cytometry

Cytometry Part A  73A: 825833, 2008

Abstract

Budding yeast Saccharoymyces cerevisiae is a powerful model system for analyzing eukaryotic

cell cycle regulation. Yeast cell cycle analysis is typically performed by visual

analysis or flow cytometry, and both have limitations in the scope and accuracy of data

obtained. This study demonstrates how multispectral imaging flow cytometry (MIFC)

provides precise quantitation of cell cycle distribution and morphological phenotypes

of yeast cells in flow. Cell cycle analysis of wild-type yeast, nap1D, and yeast overexpressing

NAP1, was performed visually, by flow cytometry and by MIFC. Quantitative morphological

analysis employed measurements of cellular length, thickness, and aspect ratio

in an algorithm to calculate a novel feature, bud length. MIFC demonstrated reliable

quantification of the yeast cell cycle compared to morphological and flow cytometric

analyses. By employing this technique, we observed both the G2/M delay and elongated

buds previously described in the nap1D strain. Using MIFC, we demonstrate that overexpression

of NAP1 causes elongated buds yet only a minor disruption in the cell cycle.

The different effects of NAP1 expression level on cell cycle and morphology suggests

that these phenotypes are independent. Unlike conventional yeast flow cytometry,

MIFC generates complete cell cycle profiles and concurrently offers multiple parameters

for morphological analysis.

 

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