10.1021/acscombsci.9b00152.s001
Che-Fan Huang
Che-Fan
Huang
Milan Mrksich
Milan
Mrksich
Profiling Protein Tyrosine Phosphatase Specificity
with Self-Assembled Monolayers for Matrix-Assisted Laser Desorption/Ionization
Mass Spectrometry and Peptide Arrays
American Chemical Society
2019
phosphatase enzymes
phosphotyrosine-containing peptide arrays
SAMDI-MS
profile phosphatase substrate selectivities
Profiling Protein Tyrosine Phosphatase Specificity
protein tyrosine phosphatases
1152Q
MALDI
2019-10-23 21:14:09
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Profiling_Protein_Tyrosine_Phosphatase_Specificity_with_Self-Assembled_Monolayers_for_Matrix-Assisted_Laser_Desorption_Ionization_Mass_Spectrometry_and_Peptide_Arrays/10032140
The
opposing activities of phosphatases and kinases determine the
phosphorylation status of proteins, yet kinases have received disproportionate
attention in studies of cellular processes, with the roles of phosphatases
remaining less understood. This Research Article describes the use
of phosphotyrosine-containing peptide arrays together with matrix-assisted
laser desorption/ionization (MALDI) mass spectrometry to directly
profile phosphatase substrate selectivities. Twenty-two protein tyrosine
phosphatases were characterized with the arrays to give a profile
of their specificities. An analysis of the data revealed that certain
residues in the substrates had a conserved effect on activity for
all enzymes tested, including the general rule that inclusion of a
basic lysine or arginine residue on either side of the phosphotyrosine
decreased activity. This insight also provides a new perspective on
the role of a R1152Q mutant in the insulin receptor, which is known
to exhibit a lower phosphorylation level and which this work suggests
may be due to an increased activity toward phosphatase enzymes. The
use of self-assembled monolayers for matrix-assisted laser desorption/ionization
mass spectrometry (SAMDI-MS) to provide a rapid and quantitative assay
of phosphatase enzymes will be important to gaining a more complete
understanding of the biochemistry and biology of this important enzyme
class.