Figure 8 .

Trafficking and regulation of Chs2. Cell cycle-regulated expression of CHS2 peaks at the G₂-M phase transition, and Chs2 is synthesized at the ER. Phosphorylation of Chs2 by Cdk1 retains Chs2 in the ER. Upon chromosomal separation, Cdc14-dependent dephosphorylation of Chs2 allows release of the protein from the ER and its transit to the mother cell–bud junction. Inn1 and Cyk3, localized at the division site, are involved in Chs2 activation. After primary septum formation is complete, Chs2 is endocytosed and degraded. Localization, function, and subsequent removal of Chs2 when the primary septum is complete depend on phosphorylation by Dbf2. Figure is adapted from Lesage and Bussey (2006).