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1.
Biosci Biotechnol Biochem ; 88(7): 824-829, 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38664007

ABSTRACT

We found that the culture broth of fungi showed anti-fungal activity against multidrug-sensitive budding yeast. However, we could not identify the anti-fungal compound due to the small quantity. Therefore, we attempted to increase the productivity of the target compound by the introduction of a global secondary metabolism regulator, laeA to the strain, which led to the successful isolation of 10-folds greater amount of MS-347a (1) than Aspergillus sp. FKI-5362. Compound 1 was not effective against Candida albicans and the detailed anti-fungal activity of 1 remains unverified. After our anti-fungal activity screening, 1 was found to inhibit the growth of broad plant pathogenic fungal species belonging to the Ascomycota. It is noteworthy that 1 showed little insecticidal activity against silkworms, suggesting its selective biological activity against plant pathogenic fungi. Our study implies that the combination strategy of multidrug-sensitive yeast and the introduction of laeA is useful for new anti-fungal drug discovery.


Subject(s)
Drug Discovery , Saccharomyces cerevisiae , Saccharomyces cerevisiae/drug effects , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Drug Discovery/methods , Candida albicans/drug effects , Secondary Metabolism , Fungicides, Industrial/pharmacology , Antifungal Agents/pharmacology , Antifungal Agents/chemistry , Microbial Sensitivity Tests , Ascomycota/drug effects , Ascomycota/genetics , Aspergillus/drug effects , Aspergillus/genetics , Aspergillus/metabolism , Drug Evaluation, Preclinical/methods , Saccharomyces cerevisiae Proteins/genetics , Saccharomyces cerevisiae Proteins/metabolism , Fungal Proteins/genetics , Fungal Proteins/metabolism
2.
Prog Rehabil Med ; 7: 20220004, 2022.
Article in English | MEDLINE | ID: mdl-35178482

ABSTRACT

BACKGROUND: COVID-19 is associated with an increased risk of venous thromboembolism (VTE), and prophylactic anticoagulation is recommended for the prevention of VTE in COVID-19 patients. We encountered a patient with COVID-19 who developed iliopsoas hematoma (IPH) that was likely caused by prophylactic anticoagulation against VTE; we report the case here because IPH is an important risk in rehabilitation treatment. CASE: The patient was a 73-year-old man with severe COVID-19 who received anticoagulation therapy from the time of admission (day 0). On day 22, decreased hemoglobin levels, muscle weakness in the left lower extremity, and pain on passive movement of the left hip joint were noted. On day 29, computed tomography (CT) was performed and revealed a mass lesion suspicious of a hematoma in the left iliopsoas muscle. On day 36, magnetic resonance imaging (MRI) was carried out to re-evaluate the mass lesion and revealed a multicystic lesion that could also have been an abscess. CT-guided puncture drainage was performed, but no pus-like material was collected; this finding led to a diagnosis of IPH. Subsequent exercise loads were gradually increased while the status of the hematoma was assessed. DISCUSSION: The prevalence of IPH in COVID-19 patients has been reported to be 7.6 cases per 1000 admissions, and the use of anticoagulation is likely to increase the risk of IPH. Because rehabilitative interventions can lead to the discovery or aggravation of IPH, the possibility of IPH should be kept in mind when providing rehabilitation treatment for COVID-19 patients.

3.
Foods ; 10(2)2021 Jan 29.
Article in English | MEDLINE | ID: mdl-33573087

ABSTRACT

Previously, we reported that apple polyphenols and their major active compounds, the flavan-3-ols and the procyanidins, can result in various health benefits in animals and humans, according to clinical studies. Here, we developed a rapid method for quantifying flavan-3-ols and procyanidins using high-performance liquid chromatography with fluorescence detection, where we investigated the amounts of flavan-3-ols and procyanidins in the Japanese major apple production centre, the Aomori Prefecture, from 2016 to 2018. The non-bagged 'Fuji (n = 609)', the bagged 'Fuji (n = 1101)', and the 'Orin (n = 504)' apples were evaluated in terms of their differences in flavan-3-ols and procyanidins based on apple variety and the controlled atmosphere storage. The bagging treatments of the 'Fuji' apples resulted in significantly higher concentrations of procyanidins, while changes in flavan-3-ols concentrations were not clearly observed by treatment. In addition, 'Orin' had a significantly higher concentration of procyanidins than that of 'Fuji'. In contrast, the controlled atmosphere storage hardly caused any changes in the flavan-3-ol and procyanidin contents. Hence, we present the concentrations of flavan-3-ols and procyanidins in major Japanese apples using the rapid high-performance liquid chromatography method with fluorescence detection.

4.
Article in English | MEDLINE | ID: mdl-30305913

ABSTRACT

BACKGROUND: Translocated chromosomal duplications occur spontaneously in many organisms; segmental duplications of large chromosomal regions are expected to result in phenotypic changes because of gene dosage effects. Therefore, experimentally generated segmental duplications in targeted chromosomal regions can be used to study phenotypic changes and determine the functions of unknown genes in these regions. Previously, we performed tandem duplication of a targeted chromosomal segment in Aspergillus oryzae. However, in tandem chromosomal duplication, duplication of chromosomal ends and multiple chromosomal duplication are difficult. In this study, we aimed to generate fungal strains with a translocated duplication or triplication of a targeted chromosomal region via break-induced replication. RESULTS: Double-strand breaks were introduced into chromosomes of parental strains by treating protoplast cells with I-SceI meganuclease. Subsequently, strains were generated by nonreciprocal translocation of a 1.4-Mb duplicated region of chromosome 2 to the end of chromosome 4. Another strain, containing a triplicated region of chromosome 2, was generated by translocating a 1.4-Mb region of chromosome 2 onto the ends of chromosomes 4 and 7. Phenotypic analyses of the strains containing segmental duplication or triplication of chromosome 2 showed remarkable increases in protease and amylase activities in solid-state cultures. Protease activity was further increased in strains containing the duplication and triplication after overexpression of the transcriptional activator of proteases prtT. This indicates that the gene-dosage effect and resulting phenotypes of the duplicated chromosomal region were enhanced by multiple duplications, and by the combination of the structural gene and its regulatory genes. Gene expression analysis, conducted using oligonucleotide microarrays, showed increased transcription of a large population of genes located in duplicated or triplicated chromosomal regions. CONCLUSION: In this study, we performed translocated chromosomal duplications and triplications of a 1.4-Mb targeted region of chromosome 2. Strains containing a duplication of chromosome 2 showed significant increases in protease and amylase activities; these enzymatic activities were further increased in the strain containing a triplication of chromosome 2. This indicates that segmental duplications of chromosomes enhance gene-dosage effects, and that the resulting phenotypes play important phenotypic roles in A. oryzae.

5.
J Stroke Cerebrovasc Dis ; 27(11): 3342-3344, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30181037

ABSTRACT

Botulinum neurotoxin injection therapy and rehabilitation have been conducted for stroke patients to reduce the spasticity of their affected limbs and improve their walking ability and daily living. Furthermore, their disability was reported to be related to muscle wasting. Supplementation of l-carnitine was reported to improve physical endurance and was used to treat sarcopenia in, for example, patients with cancer. Here, we report a case of chronic stroke with muscle wasting in a patient with improved walking endurance by l-carnitine supplementation, botulinum neurotoxin injection, and rehabilitation. A 58-year-old woman had a left putamen hemorrhage 9years before, and right spastic hemiplegia and walking disability. She could walk no more than 20m. Botulinum neurotoxin injection and rehabilitation were performed 6times every 3 months. The first time, walking speed and continuous walking distance increased as her spasticity decreased. However, the improvement declined after the second and third treatments. She had right leg pain during walking, accompanied by muscle wasting. The l-carnitine prescription contributed to the attenuation of her leg pain during walking and rapid improvement of her continuous walking distance. Walking speed and endurance further improved. In addition, the withdrawal of l-carnitine did not decrease her walking ability or induce a recurrence of her leg pain. Interestingly, creatine phosphokinase increased after l-carnitine was stopped, indicating that l-carnitine had helped to reduce muscle damage during rehabilitation. This case suggests that chronic stroke patients with muscle wasting have an abnormality in the mitochondrial energy metabolism of their muscles.


Subject(s)
Acetylcholine Release Inhibitors/administration & dosage , Botulinum Toxins/administration & dosage , Carnitine/administration & dosage , Dietary Supplements , Muscle, Skeletal/drug effects , Muscular Atrophy/drug therapy , Stroke Rehabilitation/methods , Stroke/drug therapy , Walking , Combined Modality Therapy , Disability Evaluation , Energy Metabolism/drug effects , Exercise Tolerance , Female , Gait , Humans , Injections , Middle Aged , Mitochondria, Muscle/drug effects , Mitochondria, Muscle/metabolism , Muscle, Skeletal/metabolism , Muscle, Skeletal/physiopathology , Muscular Atrophy/diagnosis , Muscular Atrophy/metabolism , Muscular Atrophy/physiopathology , Recovery of Function , Stroke/diagnosis , Stroke/metabolism , Stroke/physiopathology , Time Factors , Treatment Outcome
6.
Appl Environ Microbiol ; 80(15): 4547-58, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24837372

ABSTRACT

We describe here the first successful construction of a targeted tandem duplication of a large chromosomal segment in Aspergillus oryzae. The targeted tandem chromosomal duplication was achieved by using strains that had a 5'-deleted pyrG upstream of the region targeted for tandem chromosomal duplication and a 3'-deleted pyrG downstream of the target region. Consequently,strains bearing a 210-kb targeted tandem chromosomal duplication near the centromeric region of chromosome 8 and strains bearing a targeted tandem chromosomal duplication of a 700-kb region of chromosome 2 were successfully constructed. The strains bearing the tandem chromosomal duplication were efficiently obtained from the regenerated protoplast of the parental strains. However, the generation of the chromosomal duplication did not depend on the introduction of double-stranded breaks(DSBs) by I-SceI. The chromosomal duplications of these strains were stably maintained after five generations of culture under nonselective conditions. The strains bearing the tandem chromosomal duplication in the 700-kb region of chromosome 2 showed highly increased protease activity in solid-state culture, indicating that the duplication of large chromosomal segments could be a useful new breeding technology and gene analysis method.


Subject(s)
Aspergillus oryzae/genetics , Chromosomes, Fungal/genetics , Gene Duplication , Aspergillus oryzae/metabolism , Fungal Proteins/genetics , Fungal Proteins/metabolism , Gene Targeting
7.
Article in Japanese | MEDLINE | ID: mdl-23358340

ABSTRACT

PURPOSE: Homogeneity of static magnetic field (B(0)) is unstable for head and neck magnetic resonance (MR) examination; consequently, chemical shift selective fat suppression becomes inhomogeneous. There is a commercially available additional pad to attenuate the B(0) inhomogeneity, but it is expensive. It has been reported that uncooked rice can be used as a material in the pad, but it has hygienic and weight problems. We searched for a material which can replace the uncooked rice, and evaluated its performance. METHOD: After filling various materials into the cylindrical phantom, each material was evaluated by image distortion of gradient filed echo and spin echo single-shot echo planar images. A prototype additional pad was made with a material which showed less image distortion in the phantom experiment and is easily available in clinical examination. For comparison, an uncooked rice pad with the same volume was also prepared. Fat suppressed head and neck magnetic resonance imaging (MRI) of normal volunteers were visually compared when the three additional pads, including the commercial product, were used or not. RESULT: The polystyrene ball bullet (BB bullet) was adopted as a material for the additional pad. The improvement of the fat suppression in the head and neck MRI was almost the same between the three additional pads. BB bullet pad was the lightest. CONCLUSION: BB bullet can be used as a material of additional pad attenuating the B(0) inhomogeneity instead of uncooked rice.


Subject(s)
Magnetic Resonance Imaging/methods , Echo-Planar Imaging/methods , Head/anatomy & histology , Humans , Magnetic Fields , Neck/anatomy & histology , Oryza , Phantoms, Imaging , Polystyrenes
8.
Eukaryot Cell ; 11(4): 507-17, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22286092

ABSTRACT

Loop-out-type recombination is a type of intrachromosomal recombination followed by the excision of a chromosomal region. The detailed mechanism underlying this recombination and the genes involved in loop-out recombination remain unknown. In the present study, we investigated the functions of ku70, ligD, rad52, rad54, and rdh54 in the construction of large chromosomal deletions via loop-out recombination and the effect of the position of the targeted chromosomal region on the efficiency of loop-out recombination in Aspergillus oryzae. The efficiency of generation of large chromosomal deletions in the near-telomeric region of chromosome 3, including the aflatoxin gene cluster, was compared with that in the near-centromeric region of chromosome 8, including the tannase gene. In the Δku70 and Δku70-rdh54 strains, only precise loop-out recombination occurred in the near-telomeric region. In contrast, in the ΔligD, Δku70-rad52, and Δku70-rad54 strains, unintended chromosomal deletions by illegitimate loop-out recombination occurred in the near-telomeric region. In addition, large chromosomal deletions via loop-out recombination were efficiently achieved in the near-telomeric region, but barely achieved in the near-centromeric region, in the Δku70 strain. Induction of DNA double-strand breaks by I-SceI endonuclease facilitated large chromosomal deletions in the near-centromeric region. These results indicate that ligD, rad52, and rad54 play a role in the generation of large chromosomal deletions via precise loop-out-type recombination in the near-telomeric region and that loop-out recombination between distant sites is restricted in the near-centromeric region by chromosomal structure.


Subject(s)
Aspergillus oryzae/genetics , Chromosome Deletion , Chromosomes, Fungal/genetics , Recombination, Genetic , Aspergillus oryzae/metabolism , Carboxylic Ester Hydrolases/genetics , Centromere/genetics , Centromere/metabolism , Comparative Genomic Hybridization , DNA Breaks, Double-Stranded , DNA, Fungal/genetics , Endonucleases/metabolism , Fungal Proteins/genetics , Fungal Proteins/metabolism , Fungal Proteins/physiology , Gene Knockout Techniques , Telomere/genetics , Telomere/metabolism
9.
Mol Genet Genomics ; 287(2): 177-87, 2012 Feb.
Article in English | MEDLINE | ID: mdl-22207035

ABSTRACT

Our goal in this work was to develop a method to minimize the chromosomes of Aspergillus oryzae, to arrive at a deeper understanding of essential gene functions that will help create more efficient industrially useful strains. In a previous study, we successfully constructed a highly reduced chromosome 7 using multiple large-scale chromosomal deletions (Jin et al. in Mol Genet Genomics 283:1-12, 2010). Here, we have created a further reduced chromosome A. oryzae mutant harboring a reduced chromosome 7 and a reduced chromosome 8 both of which contain a large number of non-syntenic blocks. These are the smallest A. oryzae chromosomes that have been reported. Protoplast fusion between the two distinct chromosome-reduced mutants produced a vigorous and stable fusant which was isolated. PCR and flow cytometry confirmed that two kinds of nuclei, derived from the parent strains, existed in this fusant and that the chromosome DNA per nucleus was doubled, suggesting that the fusant was a heterozygous diploid strain. By treating the cell with 1 µg/ml benomyl, cell nuclei haploidization was induced in the stable diploid strain. Array comparative genomic hybridization and pulsed-field gel electrophoresis confirmed that the reduced chromosomes 7 and 8 co-existed in the haploid fusant and that no other chromosomal modifications had occurred. This method provides a useful tool for chromosome engineering in A. oryzae to construct an industry-useful strain.


Subject(s)
Aspergillus oryzae/genetics , Chromosome Deletion , Chromosomes, Fungal/genetics , Protoplasts/metabolism , Aspergillus oryzae/classification , Aspergillus oryzae/drug effects , Benomyl/pharmacology , Cell Fusion , Cell Nucleus/genetics , Comparative Genomic Hybridization , DNA, Fungal/genetics , Diploidy , Electrophoresis, Gel, Pulsed-Field , Flow Cytometry , Fungicides, Industrial/pharmacology , Genotype , Haploidy , Mutation , Phenotype , Protoplasts/cytology
10.
J Sep Sci ; 34(20): 2925-32, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21922668

ABSTRACT

A solid-phase extraction element based on epoxy polymer monolith was fabricated for sorptive enrichment of polar compounds from liquid and gaseous samples. After ultrasonication of the element in an aqueous solution for a given period of time, the thermal desorption (TD) using a pyrolyzer with gas chromatography/mass spectrometry (GC/MS), in which TD temperature was programmed from 50 to 250 °C for the analytes absorbed in the element, was used to evaluate the element for basic extraction performance using the aqueous standard mixtures consisting of compounds having varied polarities such as hexanol, isoamyl acetate, linalool, furfural and decanoic acid, in concentrations ranging from 10 µg/L to 1 mg/L. Excellent linear relationships were observed for all compounds in the standard mixture, except decanoic acid. In the extraction of beverages such as red wine, the extraction element showed stronger adsorption characteristics for polar compounds such as alcohols and acids than a non-polar polydimethylsiloxane-based element. This feature is derived from the main polymer structure along with hydroxyl and amino groups present in the epoxy-based monolith polymer matrix.


Subject(s)
Epoxy Resins/chemistry , Organic Chemicals/isolation & purification , Solid Phase Extraction/methods , Wine/analysis , Adsorption , Organic Chemicals/chemistry , Solid Phase Extraction/instrumentation
11.
DNA Res ; 18(3): 165-76, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21659486

ABSTRACT

We conducted genome sequencing of the filamentous fungus Aspergillus sojae NBRC4239 isolated from the koji used to prepare Japanese soy sauce. We used the 454 pyrosequencing technology and investigated the genome with respect to enzymes and secondary metabolites in comparison with other Aspergilli sequenced. Assembly of 454 reads generated a non-redundant sequence of 39.5-Mb possessing 13 033 putative genes and 65 scaffolds composed of 557 contigs. Of the 2847 open reading frames with Pfam domain scores of >150 found in A. sojae NBRC4239, 81.7% had a high degree of similarity with the genes of A. oryzae. Comparative analysis identified serine carboxypeptidase and aspartic protease genes unique to A. sojae NBRC4239. While A. oryzae possessed three copies of α-amyalse gene, A. sojae NBRC4239 possessed only a single copy. Comparison of 56 gene clusters for secondary metabolites between A. sojae NBRC4239 and A. oryzae revealed that 24 clusters were conserved, whereas 32 clusters differed between them that included a deletion of 18 508 bp containing mfs1, mao1, dmaT, and pks-nrps for the cyclopiazonic acid (CPA) biosynthesis, explaining the no productivity of CPA in A. sojae. The A. sojae NBRC4239 genome data will be useful to characterize functional features of the koji moulds used in Japanese industries.


Subject(s)
Aspergillus/genetics , Genome, Fungal , Aspergillus/metabolism , Base Sequence , DNA Transposable Elements , Multigene Family , Phylogeny
12.
Chembiochem ; 12(9): 1376-82, 2011 Jun 14.
Article in English | MEDLINE | ID: mdl-21608094

ABSTRACT

Aspergillus oryzae is a fungus widely used in traditional Japanese fermentation industries. Its inability to produce mycotoxins, due to mutation or transcriptional repression of the genes responsible for their biosynthesis, is consistent with the hypothesis that A. oryzae is a domesticated species derived from A. flavus, a wild species that is a well-known producer of aflatoxin. In contrast, the cyclopiazonic acid (CPA) biosynthetic gene (cpa) cluster in A. oryzae contains genes that have been lost in A. flavus. Through targeted gene inactivation, isolation of the corresponding metabolite, and evaluation of biological activity of the metabolite, we demonstrated that an A. oryzae-specific gene-cpaH-mediates the conversion of CPA into the less toxic 2-oxocyclopiazonic acid, a new analogue of CPA. The detoxifying properties of cpaH, which have been lost in the A. flavus pathway, reflect the relationship of the two species.


Subject(s)
Aspergillus oryzae/genetics , Aspergillus oryzae/metabolism , Indoles/metabolism , Mycotoxins/metabolism , Amino Acid Sequence , Aspergillus flavus/genetics , Aspergillus flavus/metabolism , Aspergillus oryzae/chemistry , Evolution, Molecular , Magnetic Resonance Spectroscopy , Molecular Sequence Data , Molecular Structure , Mycotoxins/genetics , Signal Transduction
13.
Eukaryot Cell ; 10(7): 945-55, 2011 Jul.
Article in English | MEDLINE | ID: mdl-21551246

ABSTRACT

Most known basic-region helix-loop-helix (bHLH) proteins belong to a superfamily of transcription factors often involved in the control of growth and differentiation. Therefore, inappropriate expression of genes encoding bHLH proteins is frequently associated with developmental dysfunction. In our previously reported study, a novel bHLH protein-encoding gene (AO090011000215) of Aspergillus oryzae was identified. The gene-disrupted strain was found to produce dense conidia, but sparse sclerotia, relative to the parent strain. Here, to further analyze its function, we generated an overexpressing strain using the A. oryzae amyB gene promoter. Genetic overexpression led to a large number of initial hyphal aggregations and then the formation of mature sclerotia; it was therefore designated sclR (sclerotium regulator). At the same time, the sclR-overexpressing strain also displayed both delayed and decreased conidiation. Scanning electron microscopy indicated that the aerial hyphae of the sclR-overexpressing strain were extremely branched and intertwined with each other. In the generation of the SclR-enhanced green fluorescent protein (EGFP) expression strain, the SclR-EGFP protein fusion was conditionally detected in the nuclei. In addition, the loss of sclR function led to rapid protein degradation and cell lysis in dextrin-polypeptone-yeast extract liquid medium. Taken together, these observations indicate that SclR plays an important role in hyphal morphology, asexual conidiospore formation, and the promotion of sclerotial production, even retaining normal cell function, at least in submerged liquid culture.


Subject(s)
Aspergillus oryzae/genetics , Aspergillus oryzae/metabolism , Basic Helix-Loop-Helix Transcription Factors/metabolism , Fungal Proteins/metabolism , Hyphae/physiology , Spores, Fungal/physiology , Aspergillus oryzae/cytology , Basic Helix-Loop-Helix Transcription Factors/genetics , DNA Primers , Fungal Proteins/genetics , Gene Expression Regulation, Fungal , Gene Knockout Techniques , Green Fluorescent Proteins/genetics , Helix-Loop-Helix Motifs/genetics , Hyphae/genetics , Polymerase Chain Reaction , Spores, Fungal/genetics
14.
Mol Genet Genomics ; 283(1): 1-12, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19855999

ABSTRACT

We aim to create an Aspergillus oryzae mutant with a highly reduced chromosome, but better growth, by eliminating the nonessential regions coding various dispensable functions for its better industrial use. In our previous study, we successfully determined the outline of essential and nonessential regions by constructing a series of large chromosomal deletions in A. oryzae chromosome 7. Based on these results, we here constructed two mutants, designated RkuAF7A and RkuAF7B, lacking 24.7 and 24% (725 and 705 kb) of wild type chromosome 7, respectively, using multiple large-scale chromosomal deletions in a recursive pyrG-mediated transformation system. Both showed higher amylase activity in DPY liquid medium and faster growth rate on malt agar medium relative to the parent strain. The two mutants also displayed soft fluffy hyphal morphology when grown in DPY liquid media. In addition, the gene expression profile obtained by DNA microarray indicated that although the deletion regions were fewer than 2% of the whole genome, the effect on whole gene expression exceeded 20%. Among these, the genes involved in secondary metabolism showed a relatively large change in their gene expression levels. Together, the constructed mutants showing better growth and potential usefulness is possibly suitable for further industrial use.


Subject(s)
Aspergillus oryzae/genetics , Chromosome Deletion , Chromosomes, Fungal/genetics , Chromosomes, Fungal/drug effects , Industrial Microbiology , Mutagenesis, Insertional , Orotic Acid/analogs & derivatives , Orotic Acid/pharmacology
15.
Fungal Genet Biol ; 47(1): 10-8, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19850144

ABSTRACT

Conidia of koji-mold Aspergillus oryzae are often used as starters in the fermented food industry. However, little is known about conidiation regulation in A. oryzae. To improve the productivity of conidia in A. oryzae, it is necessary to understand conidiation regulation in the strain. Therefore, we analyzed the conidiation regulatory system in A. oryzae using 10 kinds of conidiation regulatory gene disruptants. The phenotypes of AorfluG, AorflbA, AorflbB, AorflbC, AorflbD, AorflbE, AorbrlA, AorabaA, AorwetA, and AorfadA mutants are almost identical to those of the corresponding mutants in Aspergillus nidulans. The results indicated that the functions of conidiation regulatory genes are almost conserved between A. oryzae and A. nidulans. However, the severely reduced conidiation phenotype of the AorfluG disruptant in A. oryzae differs from the phenotype of the corresponding mutant in Aspergillus fumigatus in air-exposed culture conditions. These results suggest that A. oryzae, A. nidulans, and A. fumigatus have a G-protein signaling pathway and brlA orthologs in common, and only A. fumigatus has particular brlA activation pathways that are independent of the fluG ortholog. Furthermore, the analyses of AorflbA disruptant and AorfadA dominant-active mutants implicated that AorFadA-mediated G-protein signaling suppresses vegetative growth of A. oryzae.


Subject(s)
Aspergillus oryzae/genetics , Gene Expression Regulation, Fungal , Metabolic Networks and Pathways/genetics , Spores, Fungal/genetics , Aspergillus oryzae/growth & development , GTP-Binding Proteins/genetics , Gene Deletion , Gene Expression Profiling , Multigene Family , Signal Transduction , Spores, Fungal/growth & development
16.
Fungal Genet Biol ; 46(11): 815-24, 2009 Nov.
Article in English | MEDLINE | ID: mdl-19654050

ABSTRACT

Gene targeting is a technique of introducing a genetic trait at a predetermined site within a genome; it is also used to eliminate undesirable chromosomal regions from the relevant genome. Thus far, replacement-type recombination between two homologous regions separated by a large nonhomologous sequence has been hardly achieved probably due to the low frequency of homologous recombination in filamentous fungi. In this study, we report the successful and highly efficient deletion by replacement-type recombination of up to 470-kb regions of chromosome 8 and 200-kb region in chromosome 3, which includes a homologue of aflatoxin gene cluster, by nonhomologous end-joining deficient strains of Aspergillus oryzae. Our study results indicate that the deficiency of nonhomologous end-joining increases the distance of nonhomologous regions in replacement-type recombination, i.e., the possible deletion range in generation of large chromosomal deletion by one cycle of replacement-type recombination is increased in nonhomologous end-joining deficient strains.


Subject(s)
Aspergillus oryzae/genetics , Chromosomes, Fungal , DNA, Fungal/genetics , Gene Targeting/methods , Recombination, Genetic , Sequence Deletion
17.
Appl Environ Microbiol ; 75(18): 5943-51, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19633118

ABSTRACT

We previously developed two methods (loop-out and replacement-type recombination) for generating large-scale chromosomal deletions that can be applied to more effective chromosomal engineering in Aspergillus oryzae. In this study, the replacement-type method is used to systematically delete large chromosomal DNA segments to identify essential and nonessential regions in chromosome 7 (2.93 Mb), which is the smallest A. oryzae chromosome and contains a large number of nonsyntenic blocks. We constructed 12 mutants harboring deletions that spanned 16- to 150-kb segments of chromosome 7 and scored phenotypic changes in the resulting mutants. Among the deletion mutants, strains designated Delta5 and Delta7 displayed clear phenotypic changes involving growth and conidiation. In particular, the Delta5 mutant exhibited vigorous growth and conidiation, potentially beneficial characteristics for certain industrial applications. Further deletion analysis allowed identification of the AO090011000215 gene as the gene responsible for the Delta5 mutant phenotype. The AO090011000215 gene was predicted to encode a helix-loop-helix binding protein belonging to the bHLH family of transcription factors. These results illustrate the potential of the approach for identifying novel functional genes.


Subject(s)
Aspergillus oryzae/genetics , Genes, Fungal , Genes, Regulator , Helix-Loop-Helix Motifs , Transcription Factors/genetics , Transcription, Genetic , Amino Acid Sequence , Aspergillus oryzae/growth & development , Aspergillus oryzae/physiology , Chromosomes, Fungal/genetics , DNA, Fungal/genetics , Molecular Sequence Data , Sequence Alignment , Sequence Deletion , Spores, Fungal/growth & development
18.
J Magn Reson Imaging ; 29(6): 1471-7, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19472424

ABSTRACT

PURPOSE: To evaluate whether short-tau inversion-recovery (STIR) fat suppression is worthwhile in non-contrast-enhanced respiration-triggered free-breathing time-spatial labeling inversion pulse (Time-SLIP) renal magnetic resonance angiography (MRA) compared with chemical shift selective (CHESS) fat suppression. MATERIALS AND METHODS: Simulation-based analyses of inversion time (TI) for spatial-selective inversion-recovery (ssIR) pulse and breathing rate were performed, and confirmed on a phantom and in human subjects using a three-dimensional (3D) coherent steady-state free precession (SSFP) sequence on a 1.5T Toshiba scanner. RESULTS: The STIR fat suppression successfully suppressed signals from the intestines and parenchymous organs and provided better contrast between the arteries and the background, although an extension of TI was required for the ssIR pulse when a patient's respiration was extremely slow. CONCLUSION: STIR fat suppression provides better renal artery contrast than CHESS fat suppression in non-contrast free-breathing Time-SLIP MRA; it is also an effective screening tool for renal artery stenosis because of the lack of interference from intestinal signals. However, close attention is needed if the patient has slow respiration. As the TI for the ssIR pulse decreases, the STIR method requires faster-paced respiration.


Subject(s)
Arterial Occlusive Diseases/diagnosis , Hypertension, Renovascular/diagnosis , Kidney/blood supply , Magnetic Resonance Angiography/methods , Respiratory-Gated Imaging Techniques/methods , Aged, 80 and over , Computer Simulation , Humans , Imaging, Three-Dimensional , Male , Middle Aged , Phantoms, Imaging , Spin Labels
20.
Eukaryot Cell ; 8(3): 296-305, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19136573

ABSTRACT

The Woronin body, a unique organelle found in the Pezizomycotina, plugs the septal pore upon hyphal damage to prevent excessive cytoplasmic bleeding. Although it was previously shown that the Woronin body buds out from the peroxisome, the relationship between peroxisomal proliferation/division and Woronin body differentiation has not been extensively investigated. In this report, we examined whether Pex11 required for peroxisomal proliferation participates in Woronin body formation in Aspergillus oryzae. A. oryzae contained two orthologous PEX11 genes that were designated Aopex11-1 and Aopex11-2. Deletion of Aopex11 genes revealed that only the DeltaAopex11-1 strain showed reduced growth and enlarged peroxisomes in the presence of oleic acid as a sole carbon source, indicating a defect in peroxisomal function and proliferation. Disruption of Aopex11-1 gene impaired the Woronin body function, leading to excessive loss of the cytosol upon hyphal injury. Dual localization analysis of the peroxisome and Woronin body protein AoHex1 demonstrated that Woronin bodies fail to fully differentiate from peroxisomes in the DeltaAopex11-1 strain. Furthermore, distribution of AoHex1 was found to be peripheral in the enlarged peroxisome or junctional in dumbbell-shaped peroxisomes. Electron microscopy of the DeltaAopex11-1 strain revealed the presence of Woronin bodies that remained associated with organelles resembling peroxisomes, which was supported from the sucrose gradient centrifugation confirming that the Woronin body protein AoHex1 overlapped with the density-shifted peroxisome in the DeltaAopex11-1 strain. In conclusion, the present study describes the role of Pex11 in Woronin body differentiation for the first time.


Subject(s)
Aspergillus oryzae/genetics , Fungal Proteins/genetics , Gene Silencing , Organelles/genetics , Peroxisomes/genetics , Aspergillus oryzae/classification , Aspergillus oryzae/metabolism , Aspergillus oryzae/ultrastructure , Fungal Proteins/metabolism , Organelles/metabolism , Organelles/ultrastructure , Peroxisomes/metabolism , Peroxisomes/ultrastructure , Phylogeny
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