Identification and functions of new transporters in yeast mitochondria

The genome of Saccharomyces cerevisiae encodes 35 putative members of the m itochondrial carrier family. Known members of this family transport substra tes and products across the inner membranes of mitochondria. We are attempt ing to identify the functions of the yeast mitochondrial transporters via h igh-yield expression in Escherichia coli and/or S. cerevisiae, purification and reconstitution of their protein products into liposomes, where their t ransport properties are investigated. With this strategy, we have already i dentified the functions of seven S. cerevisiae gene products, whose structu ral and functional properties assigned them to the mitochondrial carrier fa mily. The functional information obtained in the reconstituted system and t he use of knock-out yeast strains can be usefully exploited for the investi gation of the physiological role of individual transporters. Furthermore, t he yeast carrier sequences can be used to identify the orthologous proteins in other organisms, including man. (C) 2000 Elsevier Science B.V. All righ ts reserved.