A Codon Change in β-Tubulin Which Drastically Affects Microtubule Structure in Drosophila melanogaster Fails To Produce a Significant Phenotype in Saccharomyces cerevisiae

Abstract

The relative uniformity of microtubule ultrastructure in almost all eukaryotic cells is thought to be a consequence of the conserved elements of tubulin sequence. In support of this idea, a mutation in a β-tubulin gene of Drosophila melanogaster, occurring at a highly conserved position, produces U-shaped microtubules, suggesting a defect in either nucleation or packing during assembly (M. T. Fuller, J. H. Caulton, J. A. Hutchens, T. C. Kaufman, and E. C. Raff, J. Cell Biol. 104:385-394, 1987, and J. E. Rudolph, M. Kimble, H. D. Hoyle, M. A. Subler, and E. C. Raff, Mol. Cell. Biol. 7:2231-2242, 1987). Surprisingly, we find that introducing the same mutation into the sole p-tubulin gene of Saccharomyces cerevisiae has virtually no consequences for microtubule structure or function in that organism.