Full text in pdf format

Mitotic instability of a compact mutant of Aspergillus nidulans

Yoko Bomu a Rosato^I; João Lúcio de Azevedo^II

^IDepartamento de Genética e Evolução, Instituto de Biologia, Caixa Postal 6107, 13081 Campinas, SP, Brasil
^IIInstituto de Genética, ESALQ-USP, Caixa Postal 83, 13400 Piracicaba, SP. Send correspondence to J.L.A.

ABSTRACT

A new morphological mutant of Aspergillus nidulans, obtained by mutagenesis with ultraviolet light, has been analyzed. Colonies of this mutant, designated corn-I, showed genetic instability at mitosis by producing sectors with altered morphology, including revertants to normal type. Genetic analysis of the coin-I mutant, and of derived sectors (corn-IA to corn-IE), showed in all cases a genetic determinant of morphological abnormality in linkage group V; additional genetic changes were detected in linkage groups VII and III, respectively, of the corn-IC and com-1E derivatives. The system is discussed and compared with other cases of mitotic instability in A. nidulans.

Keywords: mitotic; instability; mutant; Aspergillus nidulans.

REFERENCES

Azevedo, J.L. and Roper, J.A. (1970). Mitotic non-conformity in Aspergillus: successive and transposable genetic changes. Genet. Res., Camb. 16: 79-93.

Azevedo, J.L., Santana, E.P. and Bonatelli, R., Jr. (1977). Resistance and mitotic instability to chloroneb and 1,4 oxathiin in Aspergillus nidulans. Mutar. Res. 48: 163-172.

Bainbridge, B.W. and Roper, J.A. (1966). Observations on the effects of a chromosome duplication in Aspergillus nidulans. J. Gen. Microbiol. 42: 417-424.

Birkett, J.A. and Roper, J.A. (1977). Chromosome aberrations in Aspergillus nidulans. In: The Genetics and Physiology of Aspergillus (Smith, J.E. and Pateman, J.A., eds.). Academic Press, New York, pp. 293-303.

Burr, K.W., Roper, J.A. and Relton, J. (1982). Modification of chromosome instability in Aspergillus nidulans. J. Gen. Microbiol. 128: 2899-2907.

Carle, G.F. and Olson, M.V. (1985). An electrophoretic karyotype for yeast. Proc. NatL Acad Sci., USA, 82:3756-3760.

Case, B.L. and Roper, J.A. (1981). Mitotic processes which restore genome balance in Aspergillus nidulans. J. Gen. MicrobioL 124: 9-16.

Clutterbuck, A.J. (1974). Aspergillus nidulans. Handbook of Genetics, Vol. I. (King, R.C., ed.). Plenum Press, New York, pp. 447-510.

Clutterburck, A.J. and Glansdorff, N. (1981). Bursting of hyphal tips when transferred to acetate medium. Aspergillus News Letter 15: 29.

McCully, K.S. and Forbes, E. (1965). The use of p-fluorophenylalanine with "master strains" of Aspergillus nidulans for assigning genes to linkage groups. Genet. Res., Camb. 6: 352-359.

Nga, B.H. and Roper, J.A. (1968). Quantitative intrachromosomal changes arising at mitosis in Aspergillus nidulans. Genetics 57: 193-209.

Nga, B.H. and Roper, J.A. (1969). A system generating spontaneous intrachromosomal changes at mitosis in Aspergillus nidulans. Genet. Res., Camb, 13: 63-70.

Niffineger-Souza, D.R. and Azevedo, J.L. (1981). Growth of Aspergillus nidulans mycelia and conidia on acetate media. Aspergillus News Letter 15:27-28.

Pontecorvo, G., Roper, J.A., Hemmons, L.M., MacDonald, K.D. and Bufton, A.W.J. (1953). The genetics of Aspergillus nidulans. Adv. Genet. 5: 141-238.

Roper, J.A. (1952). Production of heterozygous diploids in filamentous fungi. Experientia 8: 1415.

Roper, J.A. and Nga, B.H. (1969). Mitotic non-conformity in Aspergillus nidulans: The production of hypodiploid and hipohaploid nuclei. Genet. Res., Camb. 14: 127-136.

Sexton, C.E. and Roper, J.A. (1984). Spontaneous duplication and transposition of a large chromosome segment in Aspergillus nidulans. J. Gen. Microbiol. 130: 583-595.