Discordance between eNOS phosphorylation and activation revealed by multispectral imaging and chemogenetic methods

Eroğlu, Emrah and Saeedi Saravi, Seyed Soheil and Sorrentino, Andrea and Steinhorn, Benjamin and Michel, Thomas (2019) Discordance between eNOS phosphorylation and activation revealed by multispectral imaging and chemogenetic methods. Proceedings of the National Academy of Sciences of the United States of America, 116 (40). pp. 20210-20217. ISSN 0027-8424 (Print) 1091-6490 (Online)

Full text not available from this repository. (Request a copy)


Nitric oxide (NO) synthesized by the endothelial isoform of nitric oxide synthase (eNOS) is a critical determinant of vascular homeostasis. However, the real-time detection of intracellular NO—a free radical gas—has been difficult, and surrogate markers for eNOS activation are widely utilized. eNOS phosphorylation can be easily measured in cells by probing immunoblots with phosphospecific antibodies. Here, we pursued multispectral imaging approaches using biosensors to visualize intracellular NO and Ca2+ and exploited chemogenetic approaches to define the relationships between NO synthesis and eNOS phosphorylation in cultured endothelial cells. We found that the G protein-coupled receptor agonists adenosine triphosphate (ATP) and histamine promoted rapid increases in eNOS phosphorylation, as did the receptor tyrosine kinase agonists insulin and Vascular Endothelial Growth Factor (VEGF). Histamine and ATP also promoted robust NO formation and increased intracellular Ca2+. By contrast, neither insulin nor VEGF caused any increase whatsoever in intracellular NO or Ca2+—despite eliciting strong eNOS phosphorylation responses. Our findings demonstrate an unexpected and striking discordance between receptor-modulated eNOS phosphorylation and NO formation in endothelial cells. Previous reports in which phosphorylation of eNOS has been studied as a surrogate for enzyme activation may need to be reassessed.
Item Type: Article
Uncontrolled Keywords: Endothelial cells; Nitric oxide synthase; Phosphorylation; Signal transduction
Divisions: Faculty of Engineering and Natural Sciences > Academic programs > Biological Sciences & Bio Eng.
Faculty of Engineering and Natural Sciences
Depositing User: Emrah Eroğlu
Date Deposited: 27 Jul 2023 11:06
Last Modified: 27 Jul 2023 11:06
URI: https://research.sabanciuniv.edu/id/eprint/46318

Actions (login required)

View Item
View Item