Protein synthesis and transport in the regenerating goldfish visual system, Neurochem

The nature of the proteins ynthesized in the goldfish retina and axonally trans-ported to the tectum during optic nerve regeneration has been examined. Elec-trophoretic analysis of labeled soluble retinal proteins by fluorography verified our previous observation ofa greatly enhanced synthesis of the microtubule sub-units. In addition, labeling of a tubulin-like protein in the retinal particulate fraction was also increased uring regeneration. Like soluble tubulin, the particulate ma-terial had an apparent MW of 53-55K and could be tyrosylated in the presence of cycloheximide and [3H]tyrosine. Comparison of post-crush and normal retinal proteins by two-dimensional gel electrophoresis al o revealed a marked enhance-ment in the labeling of two acidic 68-70K proteins. Analysis of proteins lowly transported to the optic tectum revealed changes following nerve crush similar to those observed in the retina, with enhanced labeling of both soluble and par-ticulate tubulin and of 68-70K polypeptides. The most striking change in the profile of rapidly transported protein was the appearance of a labeled 45K protein which was barely detectable in control fish