Phosphoproteomics Profiling of Receptor Kinase Mutants.

The transmembrane receptor kinase family is the largest protein kinase family in Arabidopsis. Many members of this family play critical roles in plant signaling pathways. However, many of these kinases have yet uncharacterized functions and very little is known about the direct substrates of these kinases. We have developed the "ShortPhos" method, an efficient and simple mass spectrometry (MS)-based phosphoproteomics protocol to perform comparative phosphopeptide profiling of knockout mutants of receptor-like kinases. Through this method, we are able to better understand the functional roles of plant kinases in the context of their signaling networks.