A distinct effect of transient and sustained upregulation of cellular factor XIII in the goldfish retina and optic nerve on optic nerve regeneration

Reciprocal Changes in Factor XIII and Retinal Transglutaminase Expressions in the Fish Retina During Optic Nerve Regeneration

“…On the other hand, a large number of FXIII-A positive cells accumulated in the area surrounding the optic nerve injury site within a few hours after nerve injury [3]. Nuclear staining of the crushed optic nerve sections with DAPI showed that DAPI-positive glial cells merged with FXIII-A expressing cells.…”

“…FXIII-A mRNA signals in the retina started to increase at day 1 and peaked at 3-7 days, then had decreased by 20 days after optic nerve injury (Table 95.1). The distribution of FXIII-A was confined to the RGC layers [3,4] during the period of neurite sprouting in the optic nerve regeneration process.…”

“…By the screening of a cDNA library prepared from goldfish retina at 1 day after optic nerve injury, a positive clone with a 2,560 bps fragment was 4 identified as the full-length cDNA clone of FXIII-A (DNA Data Bank of Japan; Accession No. AB622931) encoding a protein of 744 amino acid residues with a predicted molecular mass of 83.8 kDa [3]. FXIII-A mRNA signals in the retina started to increase at day 1 and peaked at 3-7 days, then had decreased by 20 days after optic nerve injury (Table 95.1).…”

“…Out of many candidate molecules, we cloned two types of transglutaminase (TG), protein cross-linking enzymes, were identified as upregulation molecules. Factor XIII-A was upregulated mainly in the first stage of regeneration [3,4], and TG R increased and had axon elongation effects only in the second period of optic nerve regeneration after nerve injury [5].…”

“…We screened for regeneration-associated genes using axotomized fish retinas to identify the molecules for the rescue and repair of mammalian CNS neurons. In our previous study [1][2][3] , four periods of goldfish optic nerve regeneration were reported: (i) the first period, preparation for neurite sprouting (0-6 days after nerve injury); (ii) the second, axon elongation (1-6 weeks after nerve injury); (iii) the third, synaptic refinement in the tectum (2-5 months after nerve injury); and (iv) the last, restoration of visual function (6 months after nerve injury). To identify the genes whose expression was specifically upregulated in each optic nerve regeneration period, a cDNA library was prepared from goldfish optic nerves and retinas after nerve injury.…”