Extracellular Signal-regulated Kinase Activation Is Required for Serine 727 Phosphorylation of STAT3 in Schwann Cells in vitro and in vivo.
10.4196/kjpp.2009.13.3.161
- Author:
Hyun Kyoung LEE
1
;
Junyang JUNG
;
Sang Hwa LEE
;
Su Yeong SEO
;
Duk Joon SUH
;
Hwan Tae PARK
Author Information
1. Department of Physiology, Medical Science Research Institute, College of Medicine, Dong-A University, Busan 602-714, Korea. phwantae@dau.ac.kr
- Publication Type:In Vitro ; Original Article
- Keywords:
STAT3;
ERK;
Schwann cells;
Interleukin-6;
Neuregulins-1;
Nerve injury
- MeSH:
Cell Nucleus;
Cytokines;
Intercellular Signaling Peptides and Proteins;
Interleukin-6;
Neuregulin-1;
Peripheral Nerve Injuries;
Peripheral Nerves;
Phosphorylation;
Phosphotransferases;
Schwann Cells;
Sciatic Nerve;
Serine
- From:The Korean Journal of Physiology and Pharmacology
2009;13(3):161-168
- CountryRepublic of Korea
- Language:English
-
Abstract:
In the peripheral nerves, injury-induced cytokines and growth factors perform critical functions in the activation of both the MEK/ERK and JAK/STAT3 pathways. In this study, we determined that nerve injury-induced ERK activation was temporally correlated with STAT3 phosphorylation at the serine 727 residue. In cultured Schwann cells, we noted that ERK activation is required for the serine phosphorylation of STAT3 by neuropoietic cytokine interleukin-6 (IL-6). Serine phosphorylated STAT3 by IL-6 was transported into Schwann cell nuclei, thereby indicating that ERK may regulate the transcriptional activity of STAT3 via the induction of serine phosphorylation of STAT3. Neuregulin-1 (NRG) also induced the serine phosphorylation of STAT3 in an ERK-dependent fashion. In contrast with the IL-6 response, serine phosphorylated STAT3 induced by NRG was not detected in the nucleus, thus indicating the non-nuclear function of serine phosphorylated STAT3 in response to NRG. Finally, we determined that the inhibition of ERK prevented injury-induced serine phosphorylation of STAT3 in an ex-vivo explants culture of the sciatic nerves. Collectively, the results of this study show that ERK may be an upstream kinase for the serine phosphorylation of STAT3 induced by multiple stimuli in Schwann cells after peripheral nerve injury.
