Molecular characterization and analysis of the acrB gene of Aspergillus nidulans: A gene identified by genetic interaction as a component of the regulatory network that includes the CreB deubiquitination enzyme

Copyright © 2003 by the Genetics Society of AmericaMutations in the acrB gene, which were originally selected through their resistance to acriflavine, also result in reduced growth on a range of sole carbon sources, including fructose, cellobiose, raffinose, and starch, and reduced utilization of ω-amino acids, including GABA and ß-alanine, as sole carbon and nitrogen sources. The acrB2 mutation suppresses the phenotypic effects of mutations in the creB gene that encodes a regulatory deubiquitinating enzyme, and in the creC gene that encodes a WD40-repeat-containing protein. Thus AcrB interacts with a regulatory network controlling carbon source utilization that involves ubiquitination and deubiquitination. The acrB gene was cloned and physically analyzed, and it encodes a novel protein that contains three putative transmembrane domains and a coiled-coil region. AcrB may play a role in the ubiquitination aspect of this regulatory network.Natasha A. Boase, Robin A. Lockington, Julian R. J. Adams, Louise Rodbourn and Joan M. Kell