Shear stress activates p60src-Ras-MAPK signaling pathways in vascular endothelial cells.
The aim of this study was to elucidate the upstream signaling mechanism that mediates the fluid shear stress activation of mitogen-activated protein kinases (MAPKs), including c-Jun NH2-terminal kinase (JNK) and extracellular signal-regulated kinases (ERKs), in vascular endothelial cells (ECs). Our results indicate that p60src is rapidly activated by fluid shear stress in bovine aortic endothelial cells (BAECs). Shear stress induction of the hemagglutinin (HA) epitope-tagged HA-JNK1 and the Myc epitope-tagged Myc-ERK2 was significantly attenuated by v-src(K295R) and c-src(K295R), the kinase-defective mutants ofv-src and c-src, respectively. HA-JNK1 and Myc-ERK2 were activated by c-src(F527), a constitutively activated form of p60src, and the activation was abolished by RasN17, a dominant-negative mutant of p2lras. In contrast, although HA-JNK1 and Myc-ERK2 were also activated by RasL61, an activated form of p21ras, the activation was not affected by v-src(K295R). These results indicate that p60src is upstream to the Ras-JNK and Ras-ERK pathways in response to shear stress. The shear stress inductions of the promoters of monocyte chemotactic protein-1 (MCP-1) and c-fos, driven by TPA-responsive element (TRE) and serum-responsive element (SRE), respectively, were attenuated by v-src(K295R). This attenuation is associated with decreased transcriptional activities of c-Jun and Elk-1, the transcription factors targeting TRE and SRE, respectively. Thus, p60src plays a critical role in the shear stress activation of MAPK pathways and induction of Activating Protein-1 (AP- 1)/TRE and Elk-1/SRE-mediated transcription in ECs.
Jalali
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Department of Bioengineering and Institute for Biomedical Engineering, University of California, San Diego, La Jolla 92093-0412, USA.
Li
Y S
YS
Sotoudeh
M
M
Yuan
S
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Li
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Chien
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Shyy
J Y
JY
D000818:Animals; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism / Q000502:physiology*; D002417:Cattle; D002478:Cells, Cultured; D004268:DNA-Binding Proteins; D004730:Endothelium, Vascular / Q000166:cytology / Q000502:physiology*; D048031:JNK Mitogen-Activated Protein Kinases; D019950:Mitogen-Activated Protein Kinase 1; D020928:Mitogen-Activated Protein Kinases; D009154:Mutation; D015688:Oncogene Protein pp60(v-src) / Q000235:genetics / Q000502:physiology*; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D016755:Proto-Oncogene Proteins c-jun / Q000378:metabolism; D016392:Proto-Oncogene Proteins pp60(c-src) / Q000235:genetics / Q000502:physiology*; D015398:Signal Transduction / Q000502:physiology*; D013314:Stress, Mechanical; D014157:Transcription Factors; D050807:ets-Domain Protein Elk-1; D018631:ras Proteins / Q000502:physiology*
D004268:DNA-Binding Proteins; D011518:Proto-Oncogene Proteins; D016755:Proto-Oncogene Proteins c-jun; D014157:Transcription Factors; D050807:ets-Domain Protein Elk-1; D015688:Oncogene Protein pp60(v-src); D016392:Proto-Oncogene Proteins pp60(c-src); D017871:Calcium-Calmodulin-Dependent Protein Kinases; D048031:JNK Mitogen-Activated Protein Kinases; D019950:Mitogen-Activated Protein Kinase 1; D020928:Mitogen-Activated Protein Kinases; D018631:ras Proteins