title: A dually located multi-HMG-box protein of Aspergillus nidulans has a crucial role in conidial and ascospore germination.
abstract: Seven HMG-box proteins of Aspergillus nidulans have been identified in the genomic databases. Three of these have the characteristics of non-specific DNA-binding proteins. One of these, AN1267 (HmbB), comprises one canonical HMG-box in its C-terminus and upstream of the canonical box two structurally related boxes, to be called Shadow-HMG-boxes. This protein defines, together with the Podospora anserina mtHMG1, a clade of proteins present in the Pezizomycotina, with orthologues in some of the Taphrinomycotina. HmbB localizes primarily to the mitochondria but occasionally in nuclei. The deletion of the cognate gene results in a number of pleiotropic effects, including those on hyphal morphology, sensitivity to oxidative stress, absence of sterigmatocystin production and changes in the profile of conidial metabolites. The most striking phenotype of deletion strains is a dramatic decrease in conidial and ascospore viability. We show that this is most likely due to the protein being essential to maintain mitochondrial DNA in spores.
authors.affiliation: University of Szeged Faculty of Sciences and Informatics, Department of Microbiology, H-6726, Szeged, Közép fasor 52, Hungary.
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Karácsony
authors.forename: Attila
authors.initials: A
authors.lastname: Gácser
authors.forename: Csaba
authors.initials: C
authors.lastname: Vágvölgyi
authors.forename: Claudio
authors.initials: C
authors.lastname: Scazzocchio
authors.forename: Zsuzsanna
authors.initials: Z
authors.lastname: Hamari
mesh_terms: D000595:Amino Acid Sequence; D001233:Aspergillus nidulans / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism* / Q000502:physiology; D002467:Cell Nucleus / Q000737:chemistry; D005656:Fungal Proteins / Q000235:genetics / Q000378:metabolism; D017353:Gene Deletion; D024002:HMGB Proteins / Q000235:genetics / Q000378:metabolism*; D050296:Microbial Viability; D008928:Mitochondria / Q000737:chemistry; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016415:Sequence Alignment; D013172:Spores, Fungal / Q000254:growth & development*
chemical_list: D005656:Fungal Proteins; D024002:HMGB Proteins