Plasma membrane nanodomains disassembly increases yeast’s lifespan

SALZMAN, VALENTINA; BUSTAMANTE TORRES, MOISES; PELLIZZA, LEONARDO; ARAN, MARTIN; AGUILAR, PABLO S.

Congreso; LIX Reunión Anual de la SAIB; 2023

SAIB

The plasma membrane (PM) of eukaryotic cells is compartmentalized into domains enriched in specificlipids and proteins. Eisosomes are protein and lipid nanodomains assembled onto the PM of thebudding yeast Saccharomyces cerevisiae. Many eisosomal proteins have been associated to stressresistance and nutrition. However, the role of proteins ́ localization in eisosomes is not clear and is a hottopic under study. Using a microfluidic device, we measured the replicative lifespan (RLS) of eisosomes ́mutants. We found that the knockout strain for the main structural protein Pil1 (disassembledeisosomes) has significantly extended lifespan (unpublished results). A decrease in the concentrationof glucose or certain amino acids in the culture medium extends RLS in S. cerevisiae. Four differentamino acid’s transporters are stored in eisosomes and diffuse all along the PM in the pil1 mutant. Westudied if the absence of eisosomal organization leads to a nutrient imbalance state extending RLS.Measuring glucose concentration in the culture media we found that extension of longevity in the pil1mutant is not given by a difference in glucose consumption. A metabolomics analysis using 1HNMRspectroscopy coupled with multivariate statistical analysis clearly distinguished differences betweenpil1 and wt strains. Interestingly, the deletion of the PIL1 gene significantly decreases the intracellularcontent of some amino acids transported by eisosomal permeases, suggesting for the first time anassociation between the extended lifespan phenotype under study and intracellular amino acids levels.As the sensitivity of the method was not sufficient to detect Trp we complete the analysis measuring3HTrp import in vivo. We found that PIL1 deletion does not generate a decrease in Trp incorporation.LIX Annual Meeting SAIB 2023General Aminoacid Control pathway activity was determined performing reporter gene assays ineisosomal mutants. RLS experiments in starving conditions together with nutrient control pathwayactivity measurements will enable us to determine whether an amino acids imbalance state isunderlying eisosome dissasembly-dependent RLS extension.