Characterization of a bovine acidic FGF cDNA clone and its expression in brain and retina.

A cDNA encoding the acidic eye-derived growth factor (EDGF II) similar to the acidic fibroblast growth factor (aFGF), a potent cell mitogen, has been isolated from a bovine retinal cDNA library. The cDNA, 4.1 kb in size, has a sequence coding for the 155 amino acids of bovine aFGF, and shows similarity with human aFGF (87% identity). The coding sequence is flanked by a 5'-untranslated region of 0.8 kb and a 3'-untranslated end of 3.0 kb. Northern blot analysis of bovine brain and retina poly(A+) RNAs showed the existence of four aFGF mRNA species. Two of these species are 9.9 and 6.0 kb in size, not abundant and could represent premessengers. The other two species, 4.2 and 2.5 kb, are abundant.