Characterization of tpp1(+) as encoding a main trehalose-6P phosphatase inthe fission yeast Schizosaccharomyces pombe

We have characterized an open reading frame of 2,454 bp on chromosome I of Schizosaccharomyces pombe as the gene encoding trehalose-6P phosphatase (tp p1(+)). Disruption of tpp1(+) caused in vivo accumulation of trehalose-6P u pon heat shock and prevented cell growth at 37 to 40 degrees C. Accumulatio n of trehalose-6P in cells hearing a chromosomal disruption of the tpp1(+) gene and containing a plasmid with tpp1(+) under the control of the thiamin e-repressible promotor correlated with tpp1(+) repression. The level of tpp 1(+) mRNA rose upon heat shock, osmostress, or oxidative stress and was neg atively controlled by cyclic AMP-dependent protein kinase activity. Express ion of tpp1(+) during oxidative or osmotic stress, but not during heat shoc k, was under positive control bu the wis1-sty1 (equivalent to phh1 and spel l mitogen-activated protein kinase pathway. Analysis of Tpp1 protein levels suggests that the synthesis of trehalose-6P phosphatase may also be subjec ted to translational or posttranslational control.