PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 10601021

Interaction between developmental and cell cycle regulators is required for morphogenesis in Aspergillus nidulans.

X S Ye·S L Lee·T D Wolkow·S L McGuire·J E Hamer·G C Wood·S A Osmani
View original source ↗Export metadata ↓

Abstract

In Aspergillus nidulans, mutation of the transcriptional regulator brlA arrests formation of asexual spore-forming structures called conidiophores but does not hinder vegetative hyphal growth. During conidiophore development a 6-fold, brlA-dependent increase in the kinase activities of NIMX(cdc2) and NIMA occurs. A similar level of kinase induction was promoted by ectopic expression of brlA. Northern and Western analysis revealed marked induction of nimX(cdc2) mRNA after ectopic expression of brlA and increased amounts of NIMX(cdc2). Therefore, nimX(cdc2) is developmentally regulated by brlA indicating a direct role for brlA in the regulation of cell cycle genes. That correct regulation of nimX(cdc2) is important for normal development was further supported by analysis of conidiophore development and septation in cell cycle specific mutants. Most noticeably, the nimX(cdc2AF) mutation promoted inappropriate septation and hindered the switch from filamentous growth to budding growth seen during conidiophore development. Therefore, in contrast to the situation previously reported for other multicellular eukaryotes, interaction between developmental regulators and cell cycle regulators is essential for normal morphogenesis in A.nidulans.

Explore related subjects

Aspergillus nidulansCDC2 Protein KinaseCell CycleCell Cycle ProteinsCell DivisionCyclinsFungal ProteinsKineticsMorphogenesisNIMA-Related Kinase 1NIMA-Related KinasesPhosphorylationProtein Serine-Threonine KinasesRNA, MessengerSpores, FungalTranscription FactorsZinc FingersJournal ArticleResearch Support, U.S. Gov't, P.H.S.

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

X S Ye, S L Lee, T D Wolkow, S L McGuire, J E Hamer, G C Wood, S A Osmani. 1999-12-15. Interaction between developmental and cell cycle regulators is required for morphogenesis in Aspergillus nidulans.. https://doi.org/10.1093/emboj%2F18.24.6994

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2026

Structural Characterization and Engineering of a GH134 β-Mannanase from Aspergillus nidulans for Enhancement of Activity and Stability.

Mannans are abundant plant hemicelluloses, and endo-β-mannanases are important biocatalysts for their conversion into functional manno-oligosaccharides. Here, we report the structural and functional characterization of a glycoside hydrolase family 134 β-mannanase from Aspergillus nidulans (AnGH134) and a structure-guided engineering strategy to improve its performance on locust bean gum. The 1.75 Å crystal structure reveals the conserved lysozyme-like fold of GH134 enzymes and supports an inverting catalytic mechanism with Glu43 and Asp55 as the putative catalytic residues. Docking, mutational, and molecular dynamics analyses indicate that AnGH134 uses an extended substrate-binding groove and that groove-exit residues and the C-terminal region contribute to productive catalysis. Guided by these findings, N-terminal fusion of CBM10 enhanced catalytic efficiency and thermal stability, whereas C-terminal fusion was detrimental. These results provide a framework for engineering GH134 mannanases.

Aspergillus nidulans↗
PubMed2026

In-Silico and Functional Characterization of EcdLp, an ABC Transporter of Aspergillus nidulans NRRL11440.

Echinocandin B (ECB) biosynthesis in Aspergillus nidulans is primarily governed by multiple genes located within the biosynthetic echinocandin (ecd) gene cluster. The contributory functions of many genes, including transcription factors and tailoring enzymes of the ecd gene cluster, have been previously studied. The present study focused on determining the role of transporter proteins, EcdLp, EcdCp, and EcdDp, in ECB efflux using in silico and biochemical approaches. The molecular docking analysis revealed that ECB relatively showed higher binding affinity for EcdLp than the other co-clustered MFS transporters EcdCp and EcdDp, suggesting a preferred substrate of EcdLp. These results were further confirmed by heterologous integration of the ecdL gene in the ABC transporters-deficient Saccharomyces cerevisiae AD1-8u⁻, confirming active efflux. However, the binding of ECB in EcdLp is distinct from the R6G binding, overlapping the promiscuous site of farnesol, resulting in inhibition of R6G efflux in a dose-dependent manner. In conclusion, these results decipher the ECB binding and efflux mechanism and unveil the evolutionarily specialized architecture of EcdLp that permits targeted metabolite export in addition to environmental responsiveness, and lay the groundwork for optimizing ECB production via transporter engineering.

Aspergillus nidulans↗