The Aspergillus nidulans METR sulphur regulator belongs to bZIP transcriptional factors.

Renata Natorff, Marzena Sienko, Jerzy Brzywczy, and Andrzej Paszewski.


A new class of tight methionine auxotrophic mutants, which can grow only on methionine as a sulphur source was obtained. Mutations in these strains are recessive and belong to the same locus, named metR. The metR gene has been localised in chromosome III between argB and phenA genes. Mutations in the metR gene are epistatic to mutations in the sulphur negative regulatory genes scon. They impair expression of some sulphur metabolism structural genes (i.e. sulphate permease, arylsulphatase, homocysteine synthase). The expression of the metRgene seems to be not regulated by sulphur source. We have cloned and characterised the genomic and cDNA copies of the metR gene. The deduced METR protein contains a leucine zipper and an adjacent basic region (bZIP), which together constitute a bipartite sequence-specific DNA-binding domain. This domain is highly similar to analogous domain of the Neurospora crassa positive-acting sulphur regulatory protein CYS3. However, no or very little homology is found in the remaining parts of the proteins. The N. crassa cys-3 gene does not complement metR mutations. This work was supported by the KBN grant no 6 P04A 035 14

abstract No: 

Fungal Genet. Newsl. 46 (Supl):

Full conference title: 

Fungal Genetics Conference 20th
    • Fungal Genetics Conference 20th (1999)