Aim of the experiment: To undertake a quantitative assessment of baseline (i.e. growth factor-replete conditions) changes in total and phosphorylated proteins within the PI3K and MAPK siganlling pathway, in addition to several other signalling components of relevance to pluripotent stem cell biology. Model system: human iPSCs expressing either wild-type *PIK3CA*, or *PIK3CA*-H1047R from either one or both endogenous alleles. Cells were fed fresh E8/F 3h before collection. To assess variability due to differences in collection timing, clones from each iPSC genotype were collected on each one of three days according to a block design, giving rise to a total of 22 cultures. RPPA technical procedure performed by Edinburgh Cancer Research Centre (Kenneth Macleod, Carragher Group) For additional information on the remaining files in this folder, see the accompanying RNotebook. If opened within the accompanying RProject alongside the .RData file, the remaining files contained within this folder should be sufficient to reproduce the results presented in the associated publication, in addition to more in-depth QC results.