FIGURE 3: A scheme of biphasic Cdc42 polarization in the G1 phase. Cdc42 polarization occurs stepwise triggered by its two GEFs: first by Bud3 and subsequently by Cdc24 [37]. Whi5 partitions the G1 phase into two temporal steps, and the ‘Start' transition corresponds to the time of the nuclear exit of approximately 50% of Whi5 [24]. The sites of Cdc42 polarization prior to the onset of cytokinesis and until a new bud appears are marked with purple color.

24. Doncic A, Falleur-Fettig M, Skotheim JM (2011). Distinct interactions select and maintain a specific cell fate. Mol Cell 43(4): 528-539. 10.1016/j.molcel.2011.06.025

37. Kang PJ, Lee ME, Park H-O (2014). Bud3 activates Cdc42 to establish a proper growth site in budding yeast. J Cell Biol 206(1): 19-28. 10.1083/jcb.201402040