- PKA and Sch9 control a molecular switch important for the proper adaptation to nutrient availability. Roosen, J., Engelen, K., Marchal, K., Mathys, J., Griffioen, G., Cameroni, E., Thevelein, J.M., De Virgilio, C., De Moor, B., Winderickx, J. Mol. Microbiol. (2005)