Figure 6

Pak1 is a critical component of the MAPK cascade in our network models. (a) Subnet shows that Pak1 leads directly to activation of Raf, Mek and Erk. (b) Distribution of Pak1 transcript levels used in construction of the initial states. Pak1 yields two clusters: a lower 'absent' cluster centered at -0.26 and an upper 'present' cluster centered at 2.16. (c) Pak1 protein and transcript levels are correlated. Protein abundance is plotted on the x-axis; transcript data (log2 scale) is plotted along the y-axis. The line represents the least-squares fit to the data. (d) Copy number profiles for the region around the Pak1 amplicon on chromosome 11. The vertical lines represent the locations of CCND1 (69 Mb) and Pak1 (76 Mb). (e) Pak1 protein levels are correlated with percent phospho-Mek1. Each dot represents data from one cell line. The line represents the least-squares fit to the data.