• Bar1 protease;
  • glycosylation;
  • secretion;
  • α-factor pheromone;
  • Sec22p


  1. Top of page
  2. Abstract
  3. References

Saccharomyces cerevisiae MATa and MATα cells secrete α-factor and α-factor pheromones. These peptides act on cells of the opposite mating type. They induce physiological changes which allow the formation of diploid cells. MATa strains produce an extracellular protease which cleaves, and thus inactivates the MATα cell-specific α-factor pheromone. This pepsin-like enzyme is encoded by the BAR1(SST1) gene and is secreted into the periplasmic space of MATa cells. We found that the Bar1p protease is already active in early compartments of the secretory pathway. Our results indicate that Bar1 protease tolerates large N-terminal extensions of its substrate and does not require Golgi-specific modifications such as outer-chain glycosylation for activity.


α-factor pheromone


endoplasmic reticulum

Sec12-α and Sec22-α

α-factor- and c-myc-tagged hybrid proteins derived from Secl2p and Sec22p

Sec12TMD-α and Sec22TMD-α

hybrid proteins lacking their TMD


transmembrane domain

A600 unit

an amount which in 1 ml of solution gives an absorbance of 1 at 600 nm in a 1-cm path length cell


  1. Top of page
  2. Abstract
  3. References
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