STE6 is required in yeast MATA cells for production of A-factor pheromone. STE6 is involved in the transport of the farnesyl-derivation of the A-factor pheromone. an [alpha-factor](in) + ATP + H2O = ADP + an [alpha-factor](out) + H(+) + phosphate Degraded via the ubiquitin system. Belongs to the ABC transporter superfamily. Alpha-factor sex pheromone exporter (TC 3.A.1.206) family.