McClean: Alpha Factor Stock
This is the standard stock solution we use for inducing the pheromone pathway in budding yeast. Generally, we find that the different batches of pheromone can be somewhat variable so it is a good idea to make up a stock that will last you through your experiment and keep it in your own -20°C box. If you have to switch stocks mid-experiment you need to do some calibration experiments to make sure the activity is the same.
α1-Mating Factor acetate salt (Sigma T6901-1mg) DMSO (Fluka 41639, Ultra for molecular biology; stored in the Flammables cabinet)
Pipet 1ml of DMSO into the vial of α-factor from Sigma. Pipet up and down and put the lid back on an swirl to dissolve all of the alpha-factor into the DMSO. Then remove the liquid and aliquot it in 100μL eppendorfs into individual eppendorfs and store these in your own -20°C box.