Table 1. Summary of Stimulators and Inhibitors of Corneal Epithelial Actin Reorganization^a.

No Effect on Actin Reorganization	Stimulate Organization of the Actin Cortical Mat	Blocked Actin Cortical Mat Organization
Albumin	Collagen (I–IV) #α2β1,α3β1, α6β1, αvβ5, α6β4	Actin inhibitors (Cytochalasin D)
Hyaluronic Acid	Fibronectin - α3β1, α5β1, α6β1, α9β1, αvβ1, αvβ6, α6β4	Phospho-tyrosine inhibitors
Antibodies IgG	Laminin (type I) α2β1, α3β1, α6β1, αvβ1, αvβ5, α6β4	Decreasing Rho protein or activity
Proteoglycans and glycosaminoglycans including CS, HS, HSPG	Vitronectin - αvβ3, αvβ6	ROCK inhibitors
Serum	LPA*	PI-3 Kinase inhibitors
	Bombesin*	MAP Kinase inhibitors

^aMolecules that had no effect on organizing the corneal epithelial actin cortical mat included proteoglycans, glycosaminoglycans, serum, albumin and antibodies (Sugrue and Hay, 1982). Most of the extracellular matrix (ECM) molecules that bound to integrin receptor subunits (Stepp, 2006) reorganized the actin cytoskeleton: these included collagens, fibronectin, laminin (Sugrue and Hay, 1982) and vitronectin (Svoboda, unpublished). Molecules that directly stimulated the Rho pathway, including lysophosphatidic acid (LPA) and bombesin, reorganized the actin cortical mat faster (15 min) than integrin stimulation (2–6 hr; Svoboda et al., 1999b). Inhibitors of actin reorganization or the signaling pathways (broad phospho-tyrosine blockers, MAP-kinase, PI-3 kinase, ROCK inhibitors, or interference with Rho or its activity) blocked reorganization of the actin cortical mat (Svoboda and Hay, 1987; Svoboda, et al., 1999b, 2004, Chu et al., 2000; Reenstra et al., 2002).

^#Integrin subunits identified in corneal epithelia (Stepp, 2006).

^*G-protein receptor- direct Rho stimulator with an Actin response in 15 min.