Serrano, A.; Puerner, C.; Plumb, E.; Chevalier, L.; Elferich, J.; Sinn, L. R.; Grigorieff, N.; Ralser, M.; Delarue, M.; Bassilana, M.; Arkowitz, R. A.

The molecular crowding of the cytoplasm impacts a range of cellular processes. Using a fluorescent microrheological probe (GEMs), we observed a striking decrease in molecular crowding during the yeast to filamentous growth transition in the human fungal pathogen Candida albicans. This decrease in crowding is due to a decrease in ribosome concentration that results in part from an inhibition of ribosome biogenesis, combined with an increase in cytoplasmic volume; leading to a dilution of the major cytoplasmic crowder. Moreover, our results suggest that inhibition of ribosome biogenesis is a trigger for C. albicans morphogenesis.