A microfluidics-based platform enables discovery of gametogenic rejuvenation factors in Saccharomyces cerevisiae

During mitotic growth, Saccharomyces cerevisiae cells age by dividing asymmetrically producing young daughter cells while retaining age-associated damage in the mother cell, which will eventually become senescent. Gametogenesis naturally and completely resets this replicative lifespan, even in replicative aged cells. Methods to quantify replicative lifespan resetting have been limited to low-throughput and labor-intensive approaches based on repeated manual micromanipulation of individual cells. Here, we introduce a high-throughput microfluidic-based assay that allows systematic characterization of factors required for gametogenic rejuvenation in S. cerevisiae. A key innovation of this method involves two inert genetic modifications that enable specific enrichment of gametes. With this technique, we confirm the rejuvenation of aged precursor cells upon completion of gametogenesis and show that we can capture a wide range of gamete replicative lifespan, consistent with known longevity mutants. Excitingly, using this technique, we identify factors involved in ER-phagy as essential for full restoration of replicative lifespan in gametes. We anticipate this novel technique will enable systematic identification of genes that mediate gametogenic rejuvenation.