Quantitative assessment of changes in cell growth, size and morphology during telomere-initiated cellular senescence in Saccharomyces cerevisiae.
Exp Cell Res
; 381(1): 18-28, 2019 08 01.
Article
en En
| MEDLINE
| ID: mdl-31075257
ABSTRACT
Telomerase-deficient cells of the budding yeast S. cerevisiae experience progressive telomere shortening and undergo senescence in a manner similar to that seen in cultured human fibroblasts. The cells exhibit a DNA damage checkpoint-like stress response, undergo changes in size and morphology, and eventually stop dividing. In this study, a new assay is described that allowed quantitation of senescence in telomerase-deficient est2 cells with applied statistics. Use of the new technique revealed that senescence was strongly accelerated in est2 mutants that had homologous recombination genes RAD51, RAD52 or RAD54 co-inactivated, but was only modestly affected when RAD55, RAD57 or RAD59 were knocked out. Additionally, a new approach for calculating population doublings indicated that loss of growth capacity occurred after approximately 64 generations in est2 cells but only 42 generations in est2 rad52â¯cells. Phase contrast microscopy experiments demonstrated that senescing est2 cells became enlarged in a time-dependent manner, ultimately exhibiting a 60% increase in cell size. Progressive alterations in physical properties were also observed, including striking changes in light scattering characteristics and cellular sedimentation rates. The results described herein will facilitate future studies of genetic and environmental factors that affect telomere shortening-associated cell senescence rates using the yeast model system.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Saccharomyces cerevisiae
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Técnicas Microbiológicas
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Telómero
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Senescencia Celular
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Telomerasa
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Proteínas de Saccharomyces cerevisiae
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Proliferación Celular
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Tamaño de la Célula
Tipo de estudio:
Prognostic_studies
Idioma:
En
Revista:
Exp Cell Res
Año:
2019
Tipo del documento:
Article
País de afiliación:
Estados Unidos