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Updated: May 11, 2026
08:58
En Face Detection of Nitric Oxide and Superoxide in Endothelial Layer of Intact Arteries
Published on: February 25, 2016
MAP kinases bind endothelial nitric oxide synthase.
Carol A Chrestensen1, Jonathan L McMurry, John C Salerno
1Department of Chemistry & Biochemistry, Kennesaw State University, Kennesaw, GA 30144-1203, USA.
FEBS Open Bio
|May 8, 2013
Summary
Endothelial nitric oxide synthase (eNOS) directly binds mitogen-activated protein kinases (MAPKs) like p38 and ERK. This interaction, modulated by calmodulin, suggests MAPKs regulate NOS activity, impacting vascular tone and angiogenesis.
Area of Science:
- Biochemistry
- Molecular Biology
- Cell Signaling
Background:
- Endothelial nitric oxide synthase (eNOS) is crucial for vascular homeostasis.
- Mitogen-activated protein kinases (MAPKs) are key regulators of cellular processes.
- The interaction between eNOS and MAPKs has not been fully elucidated.
Purpose of the Study:
- To investigate the direct binding interactions between eNOS and specific MAPKs (p38 and ERK).
- To characterize the kinetics and affinity of these binding events.
- To explore the role of calmodulin in modulating p38-eNOS interactions.
Main Methods:
- Utilized optical biosensing to measure binding kinetics and affinity.
- Employed calmodulin titration to assess its effect on p38-eNOS binding.
- Investigated the formation of ternary complexes.
Main Results:
- eNOS directly bound p38 and ERK with nanomolar affinity and complex kinetics.
- Binding was found to be diffusion-limited.
- Neuronal NOS showed weaker binding to p38.
- Calmodulin inhibited p38-eNOS binding and promoted dissociation, suggesting ternary complex formation.
Conclusions:
- MAPKs, particularly p38, directly interact with and likely regulate eNOS activity.
- Calmodulin plays a role in modulating this interaction.
- These findings have significant implications for understanding signaling pathways in angiogenesis and vascular tone regulation.
Keywords:
AI, autoinhibitory element of nitric oxide synthaseATF, activating transcription factorAkt, v-akt murine thymoma viral oncogene homolog 1 (a.k.a, protein kinase B)BAEC, bovine aortic endothelial cellsCaM, calmodulinERKERK1/2, mitogen activated protein kinase 1 and 2MAP kinaseMEF, myocyte enhancer factorMK or MAPKAP kinase, mitogen activated protein kinase activated protein kinaseNitric oxide synthaseOptical biosensingPKA, protein kinase AeNOS, endothelial nitric oxide synthasenNOS, neuronal nitric oxide synthasep38More Related Videos
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