De novo protein synthesis is essential for thermotolerance acquisition in a Saccharomyces cerevisiae trehalose synthase mutant

Abstract

Heat shock (25~ to 37~ for 30 rain) acquisition of thennotolerance (at 50~ was observed in a yeast trehalose synthase mutant and the corresponding control strain. The acquisition of thennotolerance in the control strain was maintained for a significantly longer time than in the trehalose synthase mutant. The heat shock was associated with the synthesis of specific heat shock proteins and, in the case of the control strain, also trehalose accumulation. Inhibition of protein synthesis during the heat shock totally abolished acquisition of thermotolerance in both strains but not trehalose accumulation in the control. It was concluded that trehalose may only be required for prolonged stress protection while heat shock proteins are required for heat shock acquisition of thermotolerance.

Role of Trehalose Biosynthesis in Aspergillus fumigatus Development, Stress Response, and Virulence

“…In addition to serving as a reserve carbohydrate in development, trehalose protects actively growing cells from environmental injury. Thermosensitivity is a common defect of trehalosedeficient fungi, including S. cerevisiae (18), C. albicans (1,43), and A. nidulans (8,16). In wild-type A. fumigatus, trehalose levels increased during exposure to 50°C, and the ⌬tpsAB double mutant had a severe defect in growth and viability at this temperature.…”

Use of physiological constraints to identify quantitative design principles for gene expression in yeast adaptation to heat shock

“…For example, heat shock also induces adaptation responses to other stresses [ 6 ]. Cells that are adapted to a mild heat shock become resistant to larger temperatures shifts [ 7 ], to oxidative stress [ 8 ], to osmotic stress and to freezing [ 9 , 10 ]. Physiological events that are common to the different types of stress responses include cell cycle arrest [ 11 , 12 ], changes in cell wall architecture [ 13 , 14 ], increase in the synthesis of heat shock proteins (most of them chaperones), and increase in the concentration of small protective molecules (glycerol and trehalose) [ 6 , 15 , 16 ].…”

The yeast response to heat shock

“…Wild type cells shifted from 30˚C to 37˚C for one hour prior to exposure to a 55˚C shock show dramatically increased survival relative to cells shifted directly from 30˚C to 55˚C (Gross and Watson 1998;Sanchez and Lindquist 1990). During this pretreatment, both the Hsf1p-mediated heat shock response and the Msn2p/4p-mediated general stress response are activated, resulting in the accumulation of HSPs and other cytoprotective proteins.…”