Epidermal growth factor receptor-stimulated intestinal epithelial cell migration requires phospholipase C activity.
OBJECTIVE
Ulceration of intestinal mucosa is rapidly followed by enterocyte migration via restitution. The aim of this study was to investigate signaling mechanisms of epidermal growth factor (EGF) receptor-stimulated monolayer restitution in a mouse intestinal epithelial cell line.


METHODS
EGF-stimulated cell migration was determined using a wound model in the presence of agonists and/or antagonists of tyrosine kinase, phospholipase C, phosphatidylinositol 3-kinase, or protein kinase C. The tyrosine phosphorylation state of the EGF receptor, phosphatidylinositol phospholipase C gamma1 (PLCgamma1), focal adhesion kinase, and cellular lysates was determined by immunodetection.


RESULTS
EGF stimulated cell migration twofold at 4, 8, and 24 hours. Inhibition of EGF receptor tyrosine kinase activity, phospholipase C, or phosphatidylinositol 3-kinase attenuated EGF-induced intestinal cell migration. Pretreatment of cells with phorbol 12-myristate 13-acetate, known to down-regulate protein kinase C expression, blocked EGF-induced cell migration. Increased tyrosine phosphorylation of the EGF receptor and PLCgamma1 was detected within 5 minutes after wounding.


CONCLUSIONS
EGF-stimulated intestinal cell migration requires intact EGF receptor tyrosine kinase, phospholipase, and protein kinase C activities. PLCgamma1 may be a key regulatory molecule in the initial EGF receptor signal transduction pathway of EGF-stimulated cell migration.
Polk
D B
DB
Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-2576, USA. d-brent.polk@mcmail.vanderbilt.edu
D000818:Animals; D002465:Cell Movement / Q000187:drug effects; D002478:Cells, Cultured; D004815:Epidermal Growth Factor / Q000494:pharmacology; D004847:Epithelial Cells / Q000502:physiology; D066246:ErbB Receptors / Q000502:physiology*; D007413:Intestinal Mucosa / Q000166:cytology*; D051379:Mice; D010766:Phosphorylation; D011493:Protein Kinase C / Q000037:antagonists & inhibitors; D051381:Rats; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D010738:Type C Phospholipases / Q000502:physiology*; D014443:Tyrosine / Q000378:metabolism
D014443:Tyrosine; D004815:Epidermal Growth Factor; D066246:ErbB Receptors; D011493:Protein Kinase C; D010738:Type C Phospholipases; D013755:Tetradecanoylphorbol Acetate