PRM of Nth1 phospho-peptides in response to AGC-kinase inhibition

Protein phosphorylation cascades play a central role in the regulation of cell growth and protein kinases PKA, Sch9 and Ypk1 take centre stage in regulating this process in S. cerevisiae. To understand how these kinases co-ordinately regulate cellular functions we compared the phospho-proteome of exponentially growing cells without and with acute chemical inhibition of PKA, Sch9 and Ypk1. Reduced phosphorylation of Nth1 S83 upon PKA- and Ypk1-inhibition was validated by Western blotting and PRM.