Use of alpha- and beta-tubulin mutants for the study of spontaneous and induced chromosomal mis-distribution in Aspergillus nidulans.
The effect of two different mutations, one involving an alpha-tubulin (tubA) and the other a beta-tubulin (benA33) gene, on somatic segregation has been investigated in diploid strains of A. nidulans. Both mutations, particularly benA33, increase the level of spontaneous chromosomal mis-distribution (CMD) phenomena, without affecting the frequency of crossing-over. The employment of homozygous strains for each of the two mutations in sensitivity tests toward various chemicals, allowed the clear identification of those interfering with microtubule assembly-disassembly processes (i.e. chloral hydrate, diamide, aminocarb, N-ethyl-maleimide, p-chlormercuribenzoate). Such compounds turned out to be very efficient and specific inducers of CMD in a somatic segregation assay performed using the wild-type strain P1. The same assay, when carried out with some of these compounds but employing a tubA/tubA strain, revealed a marked proneness toward CMD to be associated with such mutation, which is known to confer microtubule hypostability.
D001230:Aspergillus / Q000235:genetics*; D002869:Chromosome Aberrations; D005800:Genes, Fungal; D008870:Microtubules / Q000187:drug effects; D008938:Mitosis / Q000187:drug effects*; D009152:Mutagenicity Tests; D009154:Mutation; D013696:Temperature; D014404:Tubulin / Q000235:genetics*
D014404:Tubulin