• Mycobiology
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• v.30 no.3
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• pp.117-127
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• 2002

Cleistothecial development in Aspergillus nidulans(teleomorph, Emericella nidulans) was examined with the transmission electron microscopy. Cleistothecial initial was a small coiled lump of cells, ca. 6 ${\mu}m$ in diameter, which was consisted of a slightly swollen core with a short "tail" hypha. Initials were wrapped with a loose layer of hyphae. Core cells of cleistothecial initials were broad and multinucleated at first, then formed dikaryotic ascogenous cells, followed by post-meiotic tetra-nucleate or octa-nucleate protoasci and finally mature ascospores. Croziers were formed early during cleistothecium development. The peridial layer of mature cleistothecia was derived from the wrapping hyphae which originally invested the young cleistothecium. Completion of peridial layers development was associated with the depositing of a non-enzyme reactive material around peridial cells. $H\ddot{u}lle$ cell formation during the cleistothecial development appeared to be somewhat coordinated with the developmental stages of cleistothecium.

• Mycobiology
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• v.43 no.1
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• pp.31-36
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• 2015

We have previously isolated ${\varepsilon}$-COP, the ${\alpha}$-COP interactor in COPI of Aspergillus nidulans, by yeast two-hybrid screening. To understand the function of ${\varepsilon}$-COP, the $aneA^+$ gene for ${\varepsilon}$-COP/AneA was deleted by homologous recombination using a gene-specific disruption cassette. Deletion of the ${\varepsilon}$-COP gene showed no detectable changes in vegetative growth or asexual development, but resulted in decrease in the production of the fruiting body, cleistothecium, under conditions favorable for sexual development. Unlike in the budding yeast Saccharomyces cerevisiae, in A. nidulans, over-expression of ${\varepsilon}$-COP did not rescue the thermo-sensitive growth defect of the ${\alpha}$-COP mutant at $42^{\circ}C$. Together, these data show that ${\varepsilon}$-COP is not essential for viability, but it plays a role in fruiting body formation in A. nidulans.

• Journal of Microbiology and Biotechnology
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• v.3 no.2
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• pp.134-138
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• 1993

Monascus anka 732Y3 was induced from Monascus anka KFCC 11832 (IFO 4478, ATCC 16360) by ultra-violet light irradiation. The growth of this new fungus is frequently more dependent on sexual propagation than asexual propagation, compared with that of its parental strain, M. anka KFCC 11832. Less conidia than those of M. anka KFCC 11832 were observed by a microscope. The optical density of the red pigments ($OD_{500}$) produced by M. anka 732Y3 was 157, which was about 10 times higer than that of M. anka KFCC 11832. Such high production of the red pigments by the mutant could be explained by the following observations.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.95-96
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• 2012

This study makes with the environment-friendly artificial stone which doesn't use the cement and natural aggregate and increases the blast furnace slag that is the eco-friendly material that is the industrial byproduct, fly ash, and availability of the red mud and applies the coares aggregate substitute material as the cleistothecium. The experimental plan according to it indicated the compressive strength and flexural strength which is the most excellent in the mixied ratio 40% of the result degree of closeness magnetism of experimenting with the optimal mix obtained through the preceding stude.

• Mycobiology
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• v.49 no.3
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• pp.258-266
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• 2021

The velvet regulators VosA and VelB are primarily involved in spore maturation and dormancy. Previous studies found that the VosA-VelB hetero-complex coordinates certain target genes that are related to fungal differentiation and conidial maturation in Aspergillus nidulans. Here, we characterized the VosA/VelB-inhibited developmental gene vidD in A. nidulans. Phenotypic analyses demonstrated that the vidD deleted mutant exhibited defect fungal growth, a reduced number of conidia, and delayed formation of sexual fruiting bodies. The deletion of vidD decreased the amount of conidial trehalose, increased the sensitivity against heat stress, and reduced the conidial viability. Moreover, the absence of vidD resulted in increased production of sterigmatocystin. Together, these results show that VidD is required for proper fungal growth, development, and sterigmatocystin production in A. nidulans.

• Journal of Microbiology
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• v.41 no.1
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• pp.34-40
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• 2003

Aspergillus nidulans, a homothalic ascomycete, has a complete sexual reproductive cycle as well as an asexual one. Both sexual and asexual development are known to be genetically programmed, but are also strongly affected by environmental factors including nutrients, light, temperature and osmolarity. We have examined these factors to define favored conditions for fruiting body (cleistothecium) formation. In general, fruiting body formation was enhanced where carbon and nitrogen sources were sufficient. Limitation of C-source caused predominant asexual development while inhibiting sexual development. When higher concentrations of glucose were supplied, more cleistothecia were formed. Other carbon sources including lactose, galactose and glycerol made the fungus develop cleistothecia very well, whereas acetate caused asexual sporulation only. Organic nitrogen sources like casein hydrolysate and glycine, and an increase in nitrate or ammonium concentration also enhanced sexual development. In addition to nutrient effects, low levels of aerobic respiration, caused either by platesealing or treatment with various chemicals, favored sexual development. Carbon limitation, light exposure and a high concentration of salts promoted asexual development preferentially, suggesting that stress conditions may drive the cell to develop asexual sporulation while comfortable and wellnourished growth conditions favored sexual development.

• Research in Plant Disease
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• v.8 no.3
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• pp.166-170
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• 2002

Powdery mildew of mug bean was found in Suwon on September 2000. Many white and powdery mycelial colonies appeared on leaves of the plants. Conidia with fibrosin bodies were ellipsoid to elongate-ellipsoid, 25~38$\times$16~22 ${\mu}{\textrm}{m}$ in size and farmed in chains. Conidiophores were erect on superfical mycelium, 67~100 ${\mu}{\textrm}{m}$ in length. Foot cells were cylindric with 37~65$\times$10~11 ${\mu}{\textrm}{m}$ in size. Appressoria were indisdinct. Germ tubes from conidia were simple, not branched. Dark brown cleistothecia were observed on the leaves of mung bean. Cleisto-thecia were globose or subglobose, 85~1130 ${\mu}{\textrm}{m}$ in size. Wall cells were irregularly polygonal with 15~45$\times$7~26 ${\mu}{\textrm}{m}$. Appendages were mycelioid, 6-11 per ascocarp, coloured, throught when mature or paler upwards, 1~7 septa, 192~223$\times$5~7 ${\mu}{\textrm}{m}$ in size. A single sun had in a cleistothecium and was ovoid or subglobose with 62~95$\times$50~67 ${\mu}{\textrm}{m}$ in size. Ascusspore had 8 spores in an ascus and rarely developed, mostly imatuna ellipsoid-ovoid with 16~24$\times$12~16 ${\mu}{\textrm}{m}$. On the basis of morphological characters of the conidial stage and teleo-morph, the fungus was identified as Sphaerotheca phaseoli.