TY - JOUR
T1 - C-Jun N-terminal kinase 2 phosphorylates endothelial nitric oxide synthase at serine 116 and regulates nitric oxide production
AU - Park, Jung Hyun
AU - Park, Meanha
AU - Byun, Catherine Jeonghae
AU - Jo, Inho
N1 - Funding Information:
This work was supported by the RP-Grant 2009 of Ewha Womans University.
PY - 2012/1/6
Y1 - 2012/1/6
N2 - The c-Jun N-terminal kinases (JNKs) belonging to the mitogen-activated protein kinase (MAPK) superfamily play important roles in foam-cell formation, hypercholesterolemia-mediated endothelial dysfunction, and the development of obesity. Although decreased nitric oxide (NO) production via decreased phosphorylation of endothelial NO synthase at serine 1179 (eNOS-Ser 1179) was reported to be partly involved in JNK2-derived endothelial dysfunction, JNK2 seems likely to be indirectly involved in this signaling pathway. Here, using bovine aortic endothelial cells, we examined whether JNK2 directly phosphorylated eNOS-Ser 116, a putative substrate site for the MAPK superfamily, and this phosphorylation resulted in decreased NO release. JNK inhibitor SP60012 increased NO release in a time- and dose-dependent manner, which was accompanied by increased eNOS-Ser 116 phosphorylation. Purified JNK2 directly phosphorylated eNOS-Ser 116 in vitro. Ectopic expression of dominant negative JNK2 repressed eNOS-Ser 116 phosphorylation and increased NO production. Coimmunoprecipitation and confocal microscopy studies revealed a colocalization of eNOS and JNK2. However, all these observed effects were not manifested when JNK1 probes were used. Overall, this study indicates that JNK2 is a physiological kinase responsible for eNOS-Ser 116 phosphorylation and regulates NO production.
AB - The c-Jun N-terminal kinases (JNKs) belonging to the mitogen-activated protein kinase (MAPK) superfamily play important roles in foam-cell formation, hypercholesterolemia-mediated endothelial dysfunction, and the development of obesity. Although decreased nitric oxide (NO) production via decreased phosphorylation of endothelial NO synthase at serine 1179 (eNOS-Ser 1179) was reported to be partly involved in JNK2-derived endothelial dysfunction, JNK2 seems likely to be indirectly involved in this signaling pathway. Here, using bovine aortic endothelial cells, we examined whether JNK2 directly phosphorylated eNOS-Ser 116, a putative substrate site for the MAPK superfamily, and this phosphorylation resulted in decreased NO release. JNK inhibitor SP60012 increased NO release in a time- and dose-dependent manner, which was accompanied by increased eNOS-Ser 116 phosphorylation. Purified JNK2 directly phosphorylated eNOS-Ser 116 in vitro. Ectopic expression of dominant negative JNK2 repressed eNOS-Ser 116 phosphorylation and increased NO production. Coimmunoprecipitation and confocal microscopy studies revealed a colocalization of eNOS and JNK2. However, all these observed effects were not manifested when JNK1 probes were used. Overall, this study indicates that JNK2 is a physiological kinase responsible for eNOS-Ser 116 phosphorylation and regulates NO production.
KW - C-Jun N-terminal kinase 2
KW - Endothelial nitric oxide synthase
KW - Nitric oxide
KW - Phosphorylation
KW - Signal transduction
UR - http://www.scopus.com/inward/record.url?scp=84855772893&partnerID=8YFLogxK
U2 - 10.1016/j.bbrc.2011.11.112
DO - 10.1016/j.bbrc.2011.11.112
M3 - Article
C2 - 22155232
AN - SCOPUS:84855772893
SN - 0006-291X
VL - 417
SP - 340
EP - 345
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
IS - 1
ER -