UNDERSTANDING EISOSOMES MEMBRANE DOMAINS ´ ROLE IN AGING

SALZMAN, VALENTINA; PATERNOSTE, MARIBEL; AGUILAR, PABLO S

CABA

Congreso; Reunion Conjunta de Sociedades de Biociencias; 2017

SAIB, SAIC, SAI, SAFE, SAA, SAB, SAP, SAFIS, SAH

The plasma membrane (PM) of Saccharomyces cerevisiae, containsat least a dozen of different nanodomains. Particularly, eisosomesare reservoirs of more than 25 proteins including transporters,signaling molecules, proteins reported to be involved in cellularaging and proteins of unknown function. Eisosomes are structured inPM invaginations by scaffolds composed mainly by two cytoplasmicproteins Pil1 and Lsp1. In knockout strains of PIL1 domain´s organizationis lost. A model of post-mitotic cellular aging (chronologicalaging) was developed in S. cerevisiae. Cells are induced to enter anon-dividing state and the viability of the population is measured forweeks. Performing Chronological Longevity Survival (CLS) assayswe found that the Δpil1 mutant strain has an extended longevityphenotype. Lifespan extension was observed in two different S. cerevisiaegenetic backgrounds and by different viability measurementmethods. Besides, loss of Pil1 increases lifespan additively withcalorie restriction (CR) and does not influence glucose depletion.These results indicate that simulation of CR is not the underlyingmechanism for Δpil1-dependet increase in lifespan. We also usedalternative approaches to determine if Δpil1 lifespan extension wasindependent of the nutritional environment or the acidification of themedia. CLS assays were performed switching cell´s populations towater (extreme CR) and in the standard medium buffered to alkalinepH. Aging signal transduction pathways also sense amino acidsavailability. Since eisosomes colocalize with sites of tryptophan uptake,we analyzed if incorporation of this amino acid is affected ina Δpil1 mutant strain. Understanding eisosomes´ role in aging willlikely contribute to further describing S. cerevisiae aging processand domains function.