The conserved zinc finger domain of Aspergillus nidulans SteAp regulates the frequency of cleistothecial initial formation in a veA1 background.

Miller., Emily J. Telfer and Bruce L.


The SteAp of A. nidulans contains an N-terminal homeodomain, homologous to theS.cerevisiae Ste12p homeodomain, as well as two C-terminal C2/H2 Zn+2 fingers, conserved in Sterile 12-like proteins of filamentous fungi and several dimorphic fungi. Sexual development was examined in an A. nidulans veA1 strain carrying an in frame deletion of the steAC2/H2 Zn+2 finger domain. Consistent with results seen in the steA disruption mutant, the steAC2/H2 Zn+2 finger deletion mutant (steA:delta ZnF) does not affect conidiation. However, in contrast to the steAdisruption mutant, steA:delta ZnF produces fertile cleistothecia, containing wild type numbers of viable ascospores (1,000 - 100,000). steA:delta ZnF also suppresses the veA1 mutation with respect to sexual fertility and increases not only the frequency, but also the consistency with which sexual development is initiated. These results suggest steA interacts genetically with veA to regulate the frequency with which cleistothecia are initiated. The C2/H2 Zn+2 finger domain, which has not been shown to bind DNA, may provide a mechanism for this regulation.

abstract No: 

Fungal Genet. Newsl. 50 (Supl):abstract

Full conference title: 

22nd Fungal Genetics Conference
    • Fungal Genetics Conference 22nd (2001)