Long-lived asymmetrically retained proteins and approaches to identify modulators of lifespan and age-associated phenotypes of budding yeast

Abstract

The budding yeast, Saccharomyces cerevisiae, is an excellent model for studying aging because it is a highly tractable, unicellular eukaryote that experiences a short, finite, replicative lifespan (RLS). Despite these advantages, genome-wide and unbiased approaches for studying aging in yeast have been hindered by technical difficulties in observing cells of any significant age. Using the previously described Mother Enrichment Program (MEP), our lab has recently been able to identify several age- associated phenotypes. In this dissertation, I will present three projects in which I adapted the MEP to study the replicative aging process and age-associated phenotypes. In the first project, I will present the identification and characterization of a novel type of protein that we have termed Long-lived Asymmetrically Retained Proteins (LARPs). Some of the proteins identified likely contribute to the aging process. In the second project, I will present a lifespan assay that was designed to monitor the lifespan of aging yeast cells and require minimal experimentalist intervention during the aging process. The assay presented here should be amenable to high-throughput screening and allow unbiased screens for novel modulators of lifespan. In the third project, I will present an unbiased genome-wide screen for genetic suppressors of the age- associated loss of mitochondrial membrane potential. This screening strategy identified several effectors of this process and should be adaptable to study the genetic regulators of other age-associated processes.