tailieunhanh - Báo cáo Y học: Molecular interaction of neutral trehalase with other enzymes of trehalose metabolism in the fission yeast Schizosaccharomyces pombe

Trehalose metabolism is an essential component of the stress response in yeast cells. In this work we show that the products of the principal genes involved in trehalose metabolism in Schizosaccharomyces pombe, tps1+ (coding for trehalose6-P synthase, Tps1p), ntp1+ (encoding neutral trehalase, Ntp1p) and tpp1+ (that codes for trehalose-6-P phosphatase, Tpp1p), interact in vitro with each other and with themselves to form protein complexes. Disruption of the gene tps1+ blocks the activation of the neutral trehalase induced by heat shock but not by osmotic stress. We propose that this association may reflect the Tps1p-dependent requirement for thermal activation of trehalase | Eur. J. Biochem. 269 3847-3855 2002 FEBS 2002 doi Molecular interaction of neutral trehalase with other enzymes of trehalose metabolism in the fission yeast Schizosaccharomyces pombe Teresa Soto Alejandro Franco S. Padmanabhan Jero Vicente-Soler Jose Cansado and Mariano Gacto Department of Genetics and Microbiology Facultad de Biologla University of Murcia Spain Trehalose metabolism is an essential component of the stress response in yeast cells. In this work we show that the products of the principal genes involved in trehalose metabolism in Schizosaccharomyces pombe tps1 coding for trehalose-6-P synthase Tps1p ntp1 encoding neutral trehalase Ntp1p and tpp1 that codes for trehalose-6-P phosphatase Tpp1p interact in vitro with each other and with themselves to form protein complexes. Disruption of the gene tps1 blocks the activation of the neutral trehalase induced by heat shock but not by osmotic stress. We propose that this association may reflect the Tps1p-dependent requirement for thermal activation of trehalase. Data reported here indicate that following a heat shock the enzyme activity of trehalase is associated with Ntp1p dimers or trimers but not with either Ntp1p monomers or with complexes involving Tps1p. These results raise the possibility that heat shock and osmotic stress activate trehalase differentially by acting in the first case through an specific mechanism involving Tps1p-Ntp1p complexes. This study provides the first evidence for the participation of the catabolic enzyme trehalase in the structural framework of a regulatory macromolecular complex containing trehalose-6-P synthase in the fission yeast. Keywords neutral trehalase stress protein interaction. Synthesis and degradation of the nonreducing disaccharide trehalose is carried out by several enzymes that are widely distributed and conserved among prokaryotes and eukaryotes. One probable reason for this conservation is the ability of trehalose to function as