Targeting of endothelial nitric-oxide synthase to the cytoplasmic face of the Golgi complex or plasma membrane regulates Akt- versus calcium-dependent mechanisms for nitric oxide release

David J Fulton, Roger Babbitt, Stefan Zoellner, Jason Fontana, Lisette Acevedo, Timothy J. McCabe, Yasuko Iwakiri, William C. Sessa

Research output: Contribution to journalArticle

101 Scopus citations


The heterogeneous localization of endothelial nitric-oxide synthase (eNOS) on the Golgi complex versus the plasma membrane has made it difficult to dissect the regulation of each pool of enzyme. Here, we generated fusion proteins that specifically target the plasma membrane or cytoplasmic aspects of the Golgi complex and have assessed eNOS activation. Plasma membrane-targeted eNOS constructs were constitutively active, phosphorylated, and responsive to transmembrane calcium fluxes, yet were insensitive to further activation by Akt-mediated phosphorylation. In contrast, cis-Golgi complex-targeted eNOS behaved similarly to wild-type eNOS and was less sensitive to calcium-dependent activation and highly responsive to Akt-dependent phosphorylation compared with plasma membrane versions. In plasma membrane- and Golgi complex-targeted constructs, Ser1179 is critical for NO production. This study provides clear evidence for functional roles of plasma membrane- and Golgi complex-localized eNOS and supports the concept that proteins thought to be regulated and to function exclusively in the plasma membrane of cells can indeed signal and be regulated in internal Golgi membranes.

Original languageEnglish (US)
Pages (from-to)30349-30357
Number of pages9
JournalJournal of Biological Chemistry
Issue number29
Publication statusPublished - Jul 16 2004


ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology

Cite this