A novel role for activating transcription factor-2 in 15(S)-hydroxyeicosatetraenoic acid-induced angiogenesis.
To investigate the mechanisms underlying 15(S)-HETE-induced angiogenesis, we have studied the role of the small GTPase, Rac1. We find that 15(S)-HETE activated Rac1 in human retinal microvascular endothelial cells (HRMVEC) in a time-dependent manner. Blockade of Rac1 by adenovirus-mediated expression of its dominant negative mutant suppressed HRMVEC migration as well as tube formation and Matrigel plug angiogenesis. 15(S)-HETE stimulated Src in HRMVEC in a time-dependent manner and blockade of its activation inhibited 15(S)-HETE-induced Rac1 stimulation in HRMVEC and the migration and tube formation of these cells as well as Matrigel plug angiogenesis. 15(S)-HETE stimulated JNK1 in Src-Rac1-dependent manner in HRMVEC and adenovirus-mediated expression of its dominant negative mutant suppressed the migration and tube formation of these cells and Matrigel plug angiogenesis. 15(S)-HETE activated ATF-2 in HRMVEC in Src-Rac1-JNK1-dependent manner and interference with its activation via adenovirus-mediated expression of its dominant negative mutant abrogated migration and tube formation of HRMVEC and Matrigel plug angiogenesis. In addition, 15(S)-HETE-induced MEK1 stimulation was found to be dependent on Src-Rac1 activation. Blockade of MEK1 activation inhibited 15(S)-HETE-induced JNK1 activity and ATF-2 phosphorylation. Together, these findings show that 15(S)-HETE activates ATF-2 via the Src-Rac1-MEK1-JNK1 signaling axis in HRMVEC leading to their angiogenic differentiation.
T. Zhao and D. Wang contributed equally to this work; Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163.
Tieqiang
T
Zhao
T. Zhao and D. Wang contributed equally to this work; Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163.
Dong
D
Wang
Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163.
Sergey Y
SY
Cheranov
Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163.
Manjula
M
Karpurapu
Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163.
Koteswara R
KR
Chava
Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163.
Venkatesh
V
Kundumani-Sridharan
Department of Ophthalmology, University of Tennessee Health Science Center, Memphis, TN 38163.
Dianna A
DA
Johnson
Vanderbilt Eye Institute, Vanderbilt University School of Medicine, Nashville, TN 37232.
John S
JS
Penn
Department of Physiology, University of Tennessee Health Science Center, Memphis, TN 38163. Electronic address: grao@physio1.utmem.edu.
Gadiparthi N
GN
Rao
D051698:Activating Transcription Factor 2 / Q000378:metabolism*; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D003094:Collagen; D004338:Drug Combinations; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D006801:Humans; D006893:Hydroxyeicosatetraenoic Acids / Q000378:metabolism / Q000494:pharmacology*; D007797:Laminin; D048055:Mitogen-Activated Protein Kinase 8 / Q000378:metabolism; D008954:Models, Biological; D009389:Neovascularization, Pathologic / Q000139:chemically induced* / Q000378:metabolism / Q000473:pathology; D011509:Proteoglycans; D015861:Retinal Neovascularization / Q000139:chemically induced / Q000378:metabolism / Q000473:pathology; D012171:Retinal Vessels / Q000187:drug effects / Q000378:metabolism / Q000473:pathology; D015398:Signal Transduction / Q000187:drug effects; D020830:rac1 GTP-Binding Protein / Q000378:metabolism; D019061:src-Family Kinases / Q000378:metabolism
C497105:ATF2 protein, human; D051698:Activating Transcription Factor 2; D004338:Drug Combinations; D006893:Hydroxyeicosatetraenoic Acids; D007797:Laminin; D011509:Proteoglycans; C107953:RAC1 protein, human; C059485:matrigel; C025984:15-hydroxy-5,8,11,13-eicosatetraenoic acid; D003094:Collagen; D019061:src-Family Kinases; D048055:Mitogen-Activated Protein Kinase 8; D020830:rac1 GTP-Binding Protein