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Meiotic segregation of a recessive gene (w A2) included in A Dp (II-I) of Aspergillus nidulans

Marialba A.A. de Castro Prado^I; Tânia M.A. Domingues Zucchi^II

^IDepartamento de Biologia, Fundação Universidade Estadual de Maringá, Av. Colombo, 3690, 87015 Maringá, PR, Brasil
^IIDepartamento de Parasitologia, Instituto de Ciências Biomédicas (II), Cidade Universitária, Caixa Postal 4365, 05508 São Paulo, SP. Send correspondence to T.M.A.D.Z.

ABSTRACT

Strains of Aspergillus nidulans, bearing a chromosomal segment in duplicate are mitotically unstable. This research deals with the study of an A. nidulans mutant with a duplication of the meth+ segment translocated from chromosome II to I and inserted in the paba-y interval. We present evidence that this segment in duplicate also includes the wA2 mutation. Meiotic crosses (hybrid or selfed cleistothecium) of a stable segregant, bearing the duplication and being heterozygous for the markers involved on it, demonstrated segregation of the recessive marker wA2. Such segregation is interpreted as the outcome of two different aspects: total or partial deletion in one of the duplicated segments and pairing

Keywords: Gene (w a2); Aspergillus nidulans.

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