FNTA and diabetic retinopathy: Experimental models of diabetic retinopathy have demonstrated that in hyperglycemic milieu, while the levels of the prenylating enzyme, farnesyltransferase (FNTA) and GEF Vav2 are increased in the retinal vasculature, that of GDI are decreased, suggesting the importance of GDIs in diabetic retinopathy (Figure 1) [55].