Evidence for the synthesis of tubulin on membrane-bound and free ribosomes from rat forebrain.

Evidence is presented that tubulin is synthesized in cell-free systems derived from rat forebrain containing either membrane-bound or free ribosomes. Both systems were supplemented with saturating amounts of messenger RNA (from either membrane-bound of free ribosomes) and soluble enzyme and initiation factors from whole forebrain. Synthesized products were chracterized by two biochemical purification methods for brain tubulin isolation. These methods of tubulin analysis indicated that both cell free systems synthesized the same relative amounts of tubulin.