Open AccessMisfolding-prone proteins are reversibly sequestered to an Hsp42-associated granule upon chronological aging
Author(s) -
HsinYi Lee,
Jung-Chi Chao,
Kuo-Yu Cheng,
JunYi Leu
Publication year - 2018
Publication title -
journal of cell science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.384
H-Index - 278
eISSN - 1477-9137
pISSN - 0021-9533
DOI - 10.1242/jcs.220202
Subject(s) - biology , stress granule , saccharomyces cerevisiae , granule (geology) , microbiology and biotechnology , cytosol , yeast , genome , gene , biochemistry , enzyme , messenger rna , paleontology , translation (biology)
Alteration of protein localization is an important strategy for cells to regulate protein homeostasis upon environmental stresses. In the budding yeast Saccharomyces cerevisiae, many proteins relocalize and form cytosolic granules during chronological aging. However, the functions and exact components of these protein granules remain uncharacterized in most cases. In this study, we performed a genome-wide analysis of protein localization in stationary phase cells, leading to the discovery of 307 granule-forming proteins and the identification of new components in the Hsp42-stationary phase granule (Hsp42-SPG), P-bodies, Ret2 granules, and actin bodies. We further characterized the Hsp42-SPG, which contains the largest number of protein components, including many molecular chaperones, metabolic enzymes and regulatory proteins. Formation of the Hsp42-SPG efficiently downregulates the activities of sequestered components, which can be differentially released from the granule based on environmental cues. We found a similar structure in a pre-whole genome duplication yeast species, Lachancea kluyveri, suggesting that the Hsp42-SPG is an common machinery allowing chronologically aged cells to contend with changing environments using limited available energy.