|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||

* State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan, China; and
Vascular Biology Research Center, Institute of Molecular Medicine and Division of Hematology, University of Texas-Houston Health Science Center, Houston, Texas, USA
1Correspondence: Y.Z., State Key Laboratory of Virology College of Life Sciences Wuhan University Wuhan 430072, China; E-mail: yingzhu{at}whu.edu.cn or wu9988{at}vip.sina.com
We have previously shown that the nucleocapsid protein of SARS-associated coronavirus (SARS-CoV) activated cyclooxygenase-2 (COX-2) expression (1)
. In this study, we identified another viral protein, the spike of SARS-CoV, which played an important role in virus-stimulated COX-2 expression after screening all genes from the SARS-CoV genome. We found that an upstream calcium-dependent PKC isozyme PKC
that modulates the downstream ERK/NF-
B pathway through an influx of extracellular Ca2+ is induced by the spike protein of SARS-CoV. The ERK/NF-
B was identified to be involved in the activation of COX-2 promoter and production of COX-2 protein in HEK293T cells. We also demonstrated that another unusual pathway, the calcium-independent PI3K/PKC
/JNK/CREB pathway, functioned in cooperation with the calcium-dependent pathway to induce COX-2 expression upon stimulation by spike protein. This pathway can be blocked by PKC
-specific, small interfering RNA, PI3K/JNK kinase-specific inhibitors as well as dominant negative JNK. PKC
-specific siRNA also attenuated the phosphorylation of JNK. Our results provide evidence that helps us understand the function of SRAS-CoV spike protein in SARS pathogenesis.Liu, M., Yang, Y., Gu, C., Yue, Y., Wu, K. K., Wu, J., Zhu, Y. Spike protein of SARS-CoV stimulates cyclooxygenase-2 expression via both calcium-dependent and calcium-independent protein kinase C pathways.
Key Words: COX SARS-CoV spike protein transcriptional activation
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |