Full text in pdf format

Location of the suppressor of the meth A₁₇ mutation in mutant 29 of Aspergillus nidulans

Tânia M.A. Domingues Zucchi

Departamento de Parasitologia, Instituto de Ciências Biomédicas, USP, Av. Prof. Linen Prestes, 1374, Cidade Universitária, 05508-900 São Paulo, SP, Brasil. Fax number (55)(11)81-3845

ABSTRACT

A suppressor gene of meth A₁₇ was located on chromosome II. This suppressor is called silent because it appears in a strain that is meth⁺ and can only be expressed in crosses with meth A₁₇ strains. This mutation is evidenced by an alteration in the number of meth⁺ w⁺ recombinants and by the compact morphology it confers to the meth suppressed strains.
Genetic analysis of the 29 mutant was made more complex by the presence of an anti-suppressor gene that abolishes the action of the suppressor in a non related strain.
In the course of the genetic analysis the location of the anti-suppressor was determined.

Keywords: Suppressor; Meth A₁₇; Aspergillus nidulans.

REFERENCES

Anita, K.II., Loren, D.S. and Robert, A.S. (1980). Processing of intervening sequences; a new yeast umlaut which fails to excise intervening sequences from precursor tRNAs. Cell 19: 741-751.

*Castro-Prado, M.A.A. and Zucchi, T.M.A.D. (1991). Stabilization of a duplicated segment Dp (II-1) in an uvs mutant of Aspergillus nidulans through genetic mechanisms. Rev. Bras. Genet. 14: 239-248.

*Castro-Prado, M.A.A. and Zucchi, T.M.A.D. (1992). Meiotic segregation of a recessive gene (w A₂) included in a Dp (II-I) of Aspergillus nidulans. Rev. Bras. Genet. 14: 249-260.

Gallucci, E. and Garen, A. (1966). Suppressor genes of nonsense mutants. II. The su 4 and su 5 suppressor genes of Escherichia coli. J. Mol. Biology 15: 193-200.

Laien, II., Gorman, J. and Bock, R.M. (1978). Isopentenyladenosine deficient tRNA from an antisuppressor mutant of Saccharomyces cerevisiae. Nucleic Acids Res. 5: 4329-4342.

Lewis, D. and Casselton, L.A. (1975). Missense suppression in Coprinus lagopus associated with a chromosome duplication. J. Gen. Microbiology 88: 20-26.

Liebman, S.W. and Sherman, F. (1976). Inhibition of growth by amber suppressor in yeast. Genetics 82: 233-249.

Liebman, S.W. and Sherman, F. (1979). Extrachromosomal Φ⁺ determinant suppresses nonsense mutation in yeast. J. Bact. 139: 1068-1071.

Liebman, S.W., Sherman, F. and Stewart, J.W. (1976). Isolation and characterization of amber suppressors in yeast. Genetics 82: 251-272.

*Marin, J.M. and Zucchi, T.M.A.D. (1991). Genetic analysis of some factors affecting mitotic and meiotic behavior of a mutant of Aspergillus nidulans. Rev. Bras. Genet. 14: 9-20.

*Marin, J.M. and Zucchi, T.M.A.D. (1992). The effects of a Dp (II-I) in the meiotic recombination of Aspergillus nidulans. Rev. Bras. Genet. 15: 281-290.

McReady, S.J. and Cox, B.S. (1976). Suppressor-specificity of anti-suppressors in yeast. Genet. Res. Camb. 28: 129-138.

Moon, B.P. and Kang, H.S. (1982). Studies on the mechanisms of suppression in Aspergillus nidulans. Kor. J. Microbiol. 20: 1-10.

Thuriaux, P., Minet, M., Ilofer, F. and Leupold, B. (1975). Genetic analysis of antisuppressor mutants in the fission yeast Sehyzossaccharomyces pombe. Mol. Gen. Genet. 142: 251-261.

Zucchi, T.M.A.D. (1986). Estudos de fatores genéticos que alteram as frequências dc recombinação ein Aspergillus nidulans (Eidam) Winter. "Livre Docência" Thesis, Faculdade de Odontologia, USP, São Paulo.

*Zucchi, T.M.A.D. (1990a). Isolation of putative recombination mutants of Aspergillus nidulans. Rev. Bras. Genet. 13: 409-424.

*Zucchi, T.M.A.D. (1990b). Location of the suppression of meth An nutation in the 30 mutant of Aspergillus nidulans. Rev Bras. Genet. 13: 425-443.

*Zucchi, T.M.A.D. (1992). Another meth: A₁₇ suppressor of Aspergillus nidulans. Rev Bras. Genet. 15: 267-279.

*Added after acceptance.