title: Quantitation of Met tyrosine phosphorylation using MRM-MS.
abstract: Phosphorylation has long been accepted as a key cellular regulator of cell signaling pathways. The recent development of multiple-reaction monitoring mass spectrometry (MRM-MS) provides a useful tool for measuring the absolute quantity of phosphorylation occupancy at pivotal sites within signaling proteins, even when the phosphorylation sites are in close proximity. Here, we described a targeted quantitation approach to measure the absolute phosphorylation occupancy at Y1234 and Y1235 of Met. The approach is utilized to obtain absolute occupancy of the two phosphorylation sites in the full-length recombinant Met. It is further applied to quantitate the phosphorylation state of these two sites in SNU-5 cells treated with a Met inhibitor.
authors.affiliation: Laboratory of Proteomics and Analytical Technologies, Advanced Technology Program, Frederick National Laboratory for Cancer Research, SAIC-Frederick, Inc., Frederick, MD, USA.
authors.forename: Zhaojing
authors.initials: Z
authors.lastname: Meng
authors.forename: Apurva K
authors.initials: AK
authors.lastname: Srivastava
authors.forename: Ming
authors.initials: M
authors.lastname: Zhou
authors.forename: Timothy
authors.initials: T
authors.lastname: Veenstra
mesh_terms: D006801:Humans; D013058:Mass Spectrometry; D010766:Phosphorylation; D040901:Proteomics; D019859:Proto-Oncogene Proteins c-met / Q000235:genetics / Q000378:metabolism*; D014443:Tyrosine / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*
chemical_list: D014443:Tyrosine; C491743:MET protein, human; D019859:Proto-Oncogene Proteins c-met