Advances in quantitative biology methods for studying replicative aging in Saccharomyces cerevisiae

Abstract

Aging is a complex, yet pervasive phenomenon in biology. As human cells steadily succumb to the deteriorating effects of aging, so too comes a host of age-related ailments such as neurodegenerative disorders, cardiovascular disease and cancer. Therefore, elucidation of the molecular networks that drive aging is of paramount importance to human health. Progress toward this goal has been aided by studies from simple model organisms such as Saccharomyces cerevisiae . While work in budding yeast has already revealed much about the basic biology of aging as well as a number of evolutionarily conserved pathways involved in this process, recent technological advances are poised to greatly expand our knowledge of aging in this simple eukaryote. Here, we review the latest developments in microfluidics, single-cell analysis and high-throughput technologies for studying single-cell replicative aging in S. cerevisiae . We detail the challenges each of these methods addresses as well as the unique insights into aging that each has provided. We conclude with a discussion of potential future applications of these techniques as well as the importance of single-cell dynamics and quantitative biology approaches for understanding cell aging.

Replicative Aging in Pathogenic Fungi

“…This method requires the use of a dissection microscope, which includes a microneedle. The microneedle is a 50 µm fiber optic needle with the help of which around 30–40 naïve yeast cells are lined up on a culture plate ( Figure 2 a) [ 8 , 9 ]. The microneedle then helps to separate buds from these naïve cells after the cells replicate every 1–2 h. These budding events are observed through the microscope, manually scored, and the total number of buds that a mother cell produces before senescing is recorded and used to calculate the RLS of the cell.…”

Comparative Analysis of Yeast Replicative Lifespan in Different Trapping Structures Using an Integrated Microfluidic System

“…Moreover, the height of the trapping areas could be set to be larger than the size of yeast, which reduced the mechanical compressive stress caused by the increase in the cell size during aging. [24] Although many microfluidic devices have been developed for yeast replicative aging studies, they have not been systemically compared. The aforementioned experiments were performed independently in different labs using different experimental conditions or settings (e.g., medium flow rate, microscope light intensity, etc.).…”

“…The trapping methods can be broadly divided into two strategies of mechanical and hydrodynamic trapping. [24,25] Mechanical trapping relies on physical constraints to limit the free movement of mother cells and achieve long-term immobilization. Three published studies relied on mechanical trapping.…”

“…Moreover, the height of the trapping areas could be set to be larger than the size of yeast, which reduced the mechanical compressive stress caused by the increase in the cell size during aging. [ 24 ]…”

Fitmix: An R Package for Mixture Modeling of the Budding Yeast S. cerevisiae Replicative Lifespan (RLS) Distributions

“…Recent studies show that yeast replicative aging is heterogeneous and contains at least two subpopulations [10,11], which argues for mixture models. Finite mixtures are studied and applied to several applications, especially in biological (failure data) and medical (disease distributions) areas since the end of the 19th century.…”