title: Depletion of Aspergillus nidulans cotA causes a severe polarity defect which is not suppressed by the nuclear migration mutation nudA2.
abstract: The Aspergillus nidulans homologue of Neurospora crassa cot-1, cotA, encoding a member of the NDR protein kinase family, has been cloned and expressed under the control of the conditional alcA promoter. Depletion of CotA by repression of the alcA promoter led to a severe growth defect accompanied by loss of polarity. Germlings show greatly enlarged volume of the spores and hyphae, accompanied by an increase in number of nuclei per compartment, though the nucleus/volume ratio is not significantly altered. The depleted CotA phenotype was not suppressed by a nuclear migration mutation nudA2. Double mutants showed an additive, defective phenotype, unlike the suppression of the cot-1 ts mutation by ropy mutations seen in N. crassa, suggesting a different relationship between nuclear migration and the cot signalling pathway in A. nidulans. A functional CotA-GFP fusion protein was found in punctate regions of fluorescence similar to the distribution reported for human NDR2, and as a cap at the hyphal tip.
authors.affiliation: Department of Molecular Biology and Biotechnology, University of Sheffield, Western Bank, S10 2TN, Sheffield, UK. s.a.johns@sheffield.ac.uk
authors.forename: Sarah Anne
authors.initials: SA
authors.lastname: Johns
authors.forename: Abigail Claire
authors.initials: AC
authors.lastname: Leeder
authors.forename: Mehran
authors.initials: M
authors.lastname: Safaie
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Turner
mesh_terms: D001233:Aspergillus nidulans / Q000235:genetics*; D005656:Fungal Proteins / Q000235:genetics*; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D009154:Mutation; D011401:Promoter Regions, Genetic; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D005656:Fungal Proteins; D049452:Green Fluorescent Proteins