Receptor tyrosine kinases (RTKs) control key cellular processes such as proliferation, migration and fate specification. RTKs often transduce extracellular signals via the common Ras/Raf/MEK/MAPK cytoplasmic cascade. Once MAPK/Erk, the key pathway effector kinase, is activated, it enters the nucleus where it phosphorylates target transcription factors, and in this way alters profiles of gene expression. Surprisingly, despite the critical roles played by RTK signaling in multiple developmental processes, only a handful of confirmed transcription factors that are directly targeted by MAPK/Erk have been identified to date in Drosophila. We are, therefore, utilising a high throughput genome-wide proteomics approach aimed at uncovering novel, direct nuclear MAPK/Erk targets.