Factor XIIIA induction in the retina and optic nerve after optic nerve lesion in goldfish

Abstract

Unlike mammals, adult fish CNS neurons have a capacity to regenerate their axons after nerve lesion. To study the mechanisms of gene regulation for axonal regeneration, we have investigated regeneration-associated genes in early stage of optic nerve repair process of fish. A cDNA library was constructed from axotomized retinas 24 h previously. Out of 300,000 clones, a positive clone was identified as coagulation factor XIII A subunit (factor XIIIA). Factor XIIIA is well known as the last enzyme in the blood coagulation cascade, which catalyzes fibrin clot formation. In addition, the important role of factor XIIIA on wound healing process has been recently reported. Here we found that factor XIIIA is strongly expressed in the retina and optic nerve in the early stage of optic nerve regeneration and contribute to neurite regrowth. Level of factor XIIIA mRNA increased in the optic nerve itself within a few days of axotomy. Levels of factor XIIIA mRNA started to increase in the retina 1-3 days and peaked at 7-10 days after axotomy. These changes of factor XIIIA gene expression in the retina were localized to only the ganglion cell layer. Recombinant factor XIIIA protein clearly induced neurite outgrowth from adult goldfish retina. These data suggest that upregulation of factor XIIIA contributes to the successful optic nerve regeneration. © 2012 Springer Science+Business Media, LLC.