Transforming growth factor-beta expression in rat eyes with mechanical debridement of corneal epithelium or epithelial flap.

Purpose: To compare corneal haze and transforming growth factor (TGF)-beta expression in rat eyes with mechanical debridement of corneal epithelium or a chemically induced epithelial flap.

Setting: Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Korea.

Methods: Sixty corneas from 60 Sprague-Dawley rats were treated in 1 of 4 ways using a 2.

Phosphorylation of p85 beta PIX, a Rac/Cdc42-specific guanine nucleotide exchange factor, via the Ras/ERK/PAK2 pathway is required for basic fibroblast growth factor-induced neurite outgrowth.

Guanine nucleotide exchange factors (GEFs) have been implicated in growth factor-induced neuronal differentiation through the activation of small GTPases. Although phosphorylation of these GEFs is considered an activation mechanism, little is known about the upstream of PAK-interacting exchange factor (PIX), a member of the Dbl family of GEFs. We report here that phosphorylation of p85 betaPIX/Cool/p85SPR is mediated via the Ras/ERK/PAK2 pathway.

Basic fibroblast growth factor-induced translocation of p21-activated kinase to the membrane is independent of phospholipase C-gamma1 in the differentiation of PC12 cells.

p21-activated kinase (PAK) targeting to the plasma membrane is essential for PC12 cell neurite outgrowth. Phospholipase C-gamma1 (PLC-gamma1) can mediate the PAK translocation in response to growth factors, since PLC-gamma1 binds to both tyrosine-phosphorylated receptor tyrosine kinases and PAK through its SH2 and SH3 domain, respectively. In the present study, we examined a potential role for PLC-gamma1 in the basic fibroblast growth factor (bFGF)-induced PAK translocation using stable PC12 cell lines that overexpress in a tetracycline-inducible manner either the wild-type FGFR-1 or the Y766F FGFR-1 mutant.