Endogenous, regulatory cysteine sulfenylation of ERK kinases in response to proliferative signals

Abstract

ERK-dependent signaling is key to many pathways through which extracellular signals are transduced into cell-fate decisions. One conundrum is the way in which disparate signals induce specific responses through a common, ERK-dependent kinase cascade. While studies have revealed intricate ways of controlling ERK signaling through spatiotemporal localization and phosphorylation dynamics, additional modes of ERK regulation undoubtedly remain to be discovered. We hypothesized that fine-tuning of ERK signaling could occur by cysteine oxidation. We report that ERK is actively and directly oxidized by signal-generated H2O2 during proliferative signaling, and that ERK oxidation occurs downstream of a variety of receptor classes tested in four cell lines. Furthermore, within the tested cell lines and proliferative signals, we observed that both activation loop-phosphorylated and non-phosphorylated ERK undergo sulfenylation in cells and that dynamics of ERK sulfenylation is dependent on the cell growth conditions prior to stimulation. We also tested the effect of endogenous ERK oxidation on kinase activity and report that phosphotransfer reactions are reversibly inhibited by oxidation by as much as 80 to 90%, underscoring the importance of considering this additional modification when assessing ERK activation in response to extracellular signals.

H2O2 oxidation of cysteine residues in c-Jun N-terminal kinase 2 (JNK2) contributes to redox regulation in human articular chondrocytes

“…These values are physiologically relevant as H 2 O 2 concentrations are estimated to be 10 -100 nM under steady-state conditions and are expected to be even higher under oxidative stress or near the "hot spots" of H 2 O 2 generation (42). Although we do not yet have a full understanding of how JNK2 and other signaling proteins are able to compete for reaction with H 2 O 2 in the presence of abundant and efficient peroxidase proteins such as peroxiredoxins, our data, as well as those of many other investigators, do provide clear indications that such direct oxidation can and does occur during cell signaling events (20,21,43,44).…”

Signaling Diversity Enabled by Rap1-Regulated Plasma Membrane ERK with Distinct Temporal Dynamics

“…Despite our knowledge of substrate localization, little is known about the regulation of ERK in specific subcellular compartments outside of the nucleus. This is largely due to the traditional method of using phospho-specific antibodies on whole lysates, which are equated, perhaps erroneously (50,51), with full activity, and may mask subpopulations of ERK amidst the majority population. While we know that temporal dynamics plays a major role in determining cellular processes resulting from an extracellular cue, we have not been unable to critically assess whether an individual extracellular signal can induce distinct temporal dynamics among two or more different subcellular compartments.…”

Mining for protein S-sulfenylation in Arabidopsis uncovers redox-sensitive sites

“…Notably, Cys161 resides in a conserved docking site that governs the regulatory protein interactions of HsMAPK1 (60-62). In recombinant HsMAPK1, S-sulfenylation was reported to decrease kinase activity toward a substrate protein, Elk1, with Cys161 and/or Cys166 proposed as potential oxidation-sensitive sites that could influence kinase activity given their location within the docking site (63). Noteworthy, the HsMAPK1 Cys166 corresponds to Gly in Arabidopsis MAPKs; hence, we decided to investigate the functional effect of AtMAPK4 Cys181 that corresponds to the HsMAPK1 Cys161.…”