Does Inter-Organellar Proteostasis Impact Yeast Quality and Performance During Beer Fermentation?

Abstract

with one another and with biological processes that may modulate the viability and/or vitality of yeast populations during HG/VHG beer fermentation and serial repitching.

Rethinking the role of lipids in lager yeast cells during beer fermentation from a transcriptome and systems biology perspective

“…In addition to being important during proteostasis, LDs are essential for macroautophagy , helping to assemble autophagosomes and induce mitophagy (Carmona-Gutierrez et al, 2012) and microlipophagy (Vevea et al, 2015). Notably, six upregulated proteostasis-associated genes identified in this study that are linked to the inter-organellar proteostasis mechanism (CPR5, KAR2, PDI1, PMT1, RPL5, and SSA1) (Telini et al, 2020) are also found in LD structures (Suppl. Fig.…”

“…3 and 4). All these processes are known to be modulated by the stressful conditions that yeast cells are exposed to during beer fermentation, including ethanol toxicity (Telini et al, 2020) and nitrogen and carbohydrate starvation (Gibson et al, 2007).…”

“…In fact, regulation of inter-organellar proteostasis is an important mechanism underlying stress tolerance and it was recently shown that beer fermentation in lager yeast cells promotes a so-called "interorganellar/cross-organellar communication/response" (CORE mechanism). This involves a series of signaling-associated protein networks that regulate inter-organellar proteostasis, which includes the ER and mitochondria UPRs, chaperone and co-chaperone activity, and N-glycosylation quality control pathway proteins (Telini et al, 2020). A major aspect of the inter-organellar proteostasis mechanism induced by ethanol stress is the coordination and/or activation of organellar-linked microautophagy responses, such as mitophagy (Carmona-Gutierrez et al, 2012) and lipophagy of LDs (Vevea et al, 2015).…”

Fast genetic mapping using insertion-deletion polymorphisms in Caenorhabditis elegans

“…We mapped a previously unknown iw108 mutation present in an MMP strain VC20379. VC20379 is a part of 2,007 whole-genome sequenced strains that had been inbred following mutagenesis 36 , and we found an unknown mutation that is associated with a constitutive temperature-dependent dauer mutant phenotype at 28 °C 45 . Using pooled and individual F2 mutants, we mapped the mutation to the left side of chromosome X using the i40-699 indel detection primer set (Supplementary Figure S3 ).…”

“…Next, F1 heterozygous hermaphrodites were placed in new plates as L4 larvae to reproduce F2 progeny by self-fertilization. Finally, F2 homozygous mutants were identified by their mutant phenotype, which could be clear (Clr) and blistering body 42 , squashed vulva (Sqv) at L4 larval stage 43 and associated sterility with a stereotypical morphology of embryos incapable of cytokinesis 44 , or a temperature-dependent constitutive dauer mutant phenotype 45 . Collection of temperature-dependent dauer mutants involved placing a mixed population of embryos and L1 larvae at 28 °C for 10 days in the presence of plenty of E. coli bacteria serving as food prior to a return to 20 °C to allow mutant dauer survivors to become mutant fertile adults.…”