Skip to main content
. 2006 Aug;8(8):630–644. doi: 10.1593/neo.06334

Figure 3.

Figure 3

A diagram showing growth signal-mediated c-Myc phosphorylation and ubiquitylation pathways. Growth signals such as serum stimulation activate RAS. The RAS/Raf/MEK/ERK kinase cascade phosphorylates c-Myc at S62. The RAS-PI3K/Akt cascade inhibits GSK3β activity. GSK3β mediates the phosphorylation of c-Myc at T58. Phosphorylation of T58 recruits the Pin 1 prolyl isomerase, which may catalyze cis-trans isomerization at the P63 bond. This conformational change facilitates the targeting of c-Myc by PP2A phosphatase, which dephosphorylates c-Myc at S62. Phosphorylation of T58 and dephosphorylation of S62 serve as signals that trigger subsequent ubiquitylation and degradation of c-Myc by the SCFFbw7 complex.