NEUTRAL TREHALASE NTH1P OF SACCHAROMYCES-CEREVISIAE ENCODED BY THE NTH1 GENE IS A MULTIPLE STRESS-RESPONSIVE PROTEIN

We have shown previously that expression of the NTH1 gene is increased at heat stress (40 degrees C) both at the mRNA and enzymatic activity levels, This increased expression was correlated to the requirement o f the NTH1 gene for recovery after heat shock at 50 degrees C and the presence of stress responsive elements STRE (CCCCT) 3 times in its pro moter region [S, Nwaka et al., FEBS Lett, 360 (1995) 286-290; S, Nwaka et al., J. Biol, Chem. 270 (1995) 10193-10198], We show here that exp ression of the NTH1 gene and its product, neutral trehalase (Nth1p), a re also induced by other stressors such as H2O2, CuSO4, NaAsO2, and cy cloheximide (CHX). Heat-induced expression of the NTH1 gene is shown t o be accompanied by accumulation of trehalose, In contrast, the chemic al stressors which also induce the expression of NTH1 did not lead to accumulation of trehalose under similar conditions, Our data suggest t hat: (1) heat-and chemical stress-induced expression of neutral trehal ase is largely due to de novo protein synthesis, and (2) different mec hanisms may control the heat- and chemical stress-induced expression o f NTH1 at the transcriptional level, Participation of neutral trehalas e (Nth1p) in multiple stress response dependent and independent on tre halose is discussed. (C) 1997 Federation of European Biochemical Socie ties.