2 research outputs found
Efficient Modification of Alpha-Synuclein Serine 129 by Protein Kinase CK1 Requires Phosphorylation of Tyrosine 125 as a Priming Event
S129-phosphorylated
alpha-synuclein (α-syn) is abundantly
found in Lewy-body inclusions of Parkinson’s disease patients.
Residues neighboring S129 include the α-syn tyrosine phosphorylation
sites Y125, Y133, and Y136. Here, we use time-resolved NMR spectroscopy
to delineate atomic resolution insights into the modification behaviors
of different serine and tyrosine kinases targeting these sites and
show that Y125 phosphorylation constitutes a necessary priming event
for the efficient modification of S129 by CK1, both in reconstituted
kinase reactions and mammalian cell lysates. These results suggest
that α-syn Y125 phosphorylation augments S129 modification under
physiological in vivo conditions
A Multiplexed NMR-Reporter Approach to Measure Cellular Kinase and Phosphatase Activities in Real-Time
Cell
signaling is governed by dynamic changes in kinase and phosphatase
activities, which are difficult to assess with discontinuous readout
methods. Here, we introduce an NMR-based reporter approach to directly
identify active kinases and phosphatases in complex physiological
environments such as cell lysates and to measure their individual
activities in a semicontinuous fashion. Multiplexed NMR profiling
of reporter phosphorylation states provides unique advantages for
kinase inhibitor studies and reveals reversible modulations of cellular
enzyme activities under different metabolic conditions