Current Genetics

, Volume 23, Issue 5, pp 382–387

Lack of correlation between trehalase activation and trehalose-6 phosphate synthase deactivation in cAMP-altered mutants of Saccharomyces cerevisiae

Authors

  • Juan-Carlos Argüelles
    • Departamento de Genética y Microbiologia, Facultad de BiologíaUniversidad de Murcia
  • Dolores Carrillo
    • Departamento de Genética y Microbiologia, Facultad de BiologíaUniversidad de Murcia
  • Jerónima Vicente-Soler
    • Departamento de Genética y Microbiologia, Facultad de BiologíaUniversidad de Murcia
  • Francisco Garcia-Carmona
    • Departamento de Bioquimica, Facultad de BiologíaUniversidad de Murcia
  • Mariano Gacto
    • Departamento de Genética y Microbiologia, Facultad de BiologíaUniversidad de Murcia
Original Articles

DOI: 10.1007/BF00312622

Cite this article as:
Argüelles, J., Carrillo, D., Vicente-Soler, J. et al. Curr Genet (1993) 23: 382. doi:10.1007/BF00312622

Abstract

The rise in cAMP level that follows the addition of glucose or 2,4-dinitrophenol (DNP) to stationaryphase cells of Saccharomyces cerevisiae was accompanied by a marked activation of trehalase (3-fold increase) and a concomitant deactivation of trehalose-6 phosphate synthase (50% of the basal levels). In glucose-grown exponential cells, which are deficient in glucose-induced cAMP signalling, the addition of glucose also prompted a decrease in trehalose-6 phosphate synthase, but had no effect on trehalase activity. Mutants defective in the RAS-adenylate cyclase pathway (ras1 ras2 bcy1 strain), as well as mutants containing greatly reduced protein kinase activity either cAMP-dependent (tpkw1BCY1 strains) or cAMP-independent (tpk1w1bcy1 strains), were unable to show glucose- or DNP-induced trehalase activation but still displayed a clear decrease in trehalose-6 phosphate synthase activity upon addition of these compounds. These data suggest that the activity of trehalose-6 phosphate synthase, as opposed to that of trehalase, is not controlled by the cAMP signalling pathway “in vivo”. Trehalose-6 phosphate synthase was competitively inhibited by glucose (Ki=15 mM) and resulted unaffected by ATP in assays performed “in vitro”.

Key words

TrehalaseTrehalose-6-P synthasecAMP mutantsSaccharomyces cerevisiae

Copyright information

© Springer-Verlag 1993