Familial pancreatic cancer (FPC) is broadly defined as two first-degree-relatives with pancreatic cancer (PC) and accounts for 4%-10% of PC. Several genetic syndromes, including Peutz-Jeghers syndrome, hereditary panc...Familial pancreatic cancer (FPC) is broadly defined as two first-degree-relatives with pancreatic cancer (PC) and accounts for 4%-10% of PC. Several genetic syndromes, including Peutz-Jeghers syndrome, hereditary pancreatitis, hereditary breast-ovarian cancer syndrome(HBOC), Lynch syndrome, and familial adenomatous polyposis (FAP), also have increased risks of PC, but the narrowest definition of FPC excludes these known syndromes. When compared with other familial tumors, proven genetic alterations are limited to a small proportion (<20%) and the familial aggregation is usually modest. However, an ethnic deviation (Ashkenazi Jewish>Caucasian) and a younger onset are common also in FPC. In European countries, "anticipation" is reported in FPC families, as with other hereditary syndromes; a trend toward younger age and worse prognosis is recognized in the late years. The resected pancreases of FPC kindred often show multiple pancreatic intraepithelial neoplasia (Pan IN) foci, with various K-ras mutations, similar to colorectal polyposis seen in the FAP patients. As with HBOC patients, a patient who is a BRCA mutation carrier with unresectable pancreatic cancer (accounting for 0%-19% of FPC patients) demonstrated better outcome following platinum and Poly (ADP-ribose) polymerase inhibitor treatment. Western countries have established FPC registries since the 1990 s and several surveillance projects for highrisk individuals are now ongoing to detect early PCs. Improvement in lifestyle habits, including non-smoking, is recommended for individuals at risk. In Japan, the FPC study group was initiated in 2013 and the Japanese FPC registry was established in 2014 by the Japan Pancreas Society.展开更多
An isolate GT4028 was obtained from soil samples collected from a field in Gotsu city (Kawahira), Shimane. The use of a culture suspension and culture filtrate of this isolate significantly suppressed the spore germin...An isolate GT4028 was obtained from soil samples collected from a field in Gotsu city (Kawahira), Shimane. The use of a culture suspension and culture filtrate of this isolate significantly suppressed the spore germination in Magnaporthe oryzae. The inhibitory activity of the culture filtrate was heat-stable. The formation of rice blast lesions by M. oryzae was significantly suppressed in the presence of the culture suspension of isolate GT4028. Furthermore, mycelial growth of some plant pathogenic fungi was inhibited by the isolate in a dual culture assay. Sequence analysis of 16S rDNA region of the isolate indicated that it shared similarities with species of the genus Burkholderia. Also, isolate GT4028 could be grown even in the presence of fungicides (Blastin, Kasugamycin, and Amistar) that act against M. oryzae. These results suggest that isolate GT4028 might be a potential control agent for plant protection against diseases, such as rice blast disease.展开更多
Bipolaris oryzae is the causal agent of brown leaf spot disease in rice, and its asexual spore (conidium) formation is known to be induced by near-ultraviolet (NUV) irradiation. In order to reveal the photomorphogenic...Bipolaris oryzae is the causal agent of brown leaf spot disease in rice, and its asexual spore (conidium) formation is known to be induced by near-ultraviolet (NUV) irradiation. In order to reveal the photomorphogenic response and to identify new genes upregulated by NUV irradiation, suppression subtractive hybridization (SSH) was carried out in B. oryzae. To confirm the differential gene expression in NUV-irradiated mycelia, quantitative real-time PCR (qRT-PCR) analysis was performed among 301 genes arbitrarily chosen from 1170 cDNA clones. The expression of 46 genes (named NUV01 to NUV46) was found to be significantly enhanced (>4-fold) by NUV irradiation. Sequence analysis revealed that 23 out of the 46 sequences (50%) showed significant matches to known fungal genes. The 46 genes were categorized as either BLR1-dependent or BLR1-independent expression groups using the BLR1-deficient mutant, which presumably lacks the blue/UVA-absorbing photoreceptor. This finding demonstrates that NUV irradiation can induce gene regulation, and that this response may be mediated by both a blue/UVA-absorbing photoreceptor and an as-yet-unidentified photoreceptor in B. oryzae.展开更多
Bipolaris oryzae is the causal agent of brown spot disease in rice and produces the dark pigment melanin. We isolated and characterized T4HR1 gene encoding 1,3,6,8-tetrahydroxynaphthalene (1,3,6,8-THN) reductase, whic...Bipolaris oryzae is the causal agent of brown spot disease in rice and produces the dark pigment melanin. We isolated and characterized T4HR1 gene encoding 1,3,6,8-tetrahydroxynaphthalene (1,3,6,8-THN) reductase, which converted 1,3,6,8-THN to scytalone in the melanin biosynthesis from B. oryzae. A sequence analysis showed that the T4HR1 gene encoded a putative protein of 268 amino acids showing 50% - 99% sequence identity to other fungal 1,3,6,8-THN reductases. Targeted disruption of the T4HR1 gene showed a different phenotype of mycelial color due to an accumulation of shunt products compared to those of wild-type on PDA plates using tricyclazole as a melanin biosynthesis inhibitor. A quantitative real-time PCR analysis showed that the expression of T4HR1 transcripts was enhanced by near-ultraviolet (NUV) irradiation and regulated by transcriptional factor BMR1, similar to three other melanin biosynthesis genes (polyketide synthase gene [PKS1], scytalone dehydratase gene [SCD1], and 1,3,8-THN reductase gene [THR1]) in the melanin biosynthesis of B. oryzae. These results suggested that common transcriptional mechanisms could regulate the enhanced gene expression of these melanin biosynthesis genes by NUV irradiation in B. oryzae.展开更多
A specific and sensitive polymerase chain reaction (PCR) assay based on the internal transcribed spacer (ITS) region of rDNA sequences was developed to detect endophytic and phytopathogenic fungi from needles of the J...A specific and sensitive polymerase chain reaction (PCR) assay based on the internal transcribed spacer (ITS) region of rDNA sequences was developed to detect endophytic and phytopathogenic fungi from needles of the Japanese black pine, Pinus thunbergii. Sequences of the ITS regions of Lophodermium conigenum, Lecanosticta acicola, Pestalotiopsis neglecta, Rhizosphaera kalkhoffii, and Septorioides pini-thunbergii were compared, and each specific primer pair for these species was designed. First, the designed primer pairs were tested for their specificity to detect each species. A PCR product was amplified only each combination of species and its specific primer pair, confirming the specificity of the designed primer pairs. These primer pairs were also tested on DNA extracted from the needles of P. thunbergii. The PCR products were amplified not only in needles with lesions but also in healthy needles without symptoms. Furthermore, several endophytic and phytopathogenic fungi could be simultaneously detected from the same region in a needle. The PCR-mediated detection method developed in this study will be a valuable tool for the detection of the endophytic and phytopathogenic fungi, not only as a rapid diagnostic tool for early detection but also for monitoring variations in both the quality and quantity of the endophytic and phytopathogenic fungi in needles in Japanese black pines.展开更多
Fungal strains isolated from the fruiting bodies of wild mushrooms were evaluated for fungicidal activity against Magnaporthe oryzae, the causal agent of the rice blast disease. Fungal isolates (n = 105) were obtained...Fungal strains isolated from the fruiting bodies of wild mushrooms were evaluated for fungicidal activity against Magnaporthe oryzae, the causal agent of the rice blast disease. Fungal isolates (n = 105) were obtained from 46 samples of wild mushrooms. Infection behaviors of M. oryzae were assessed in the presence of culture filtrates from 90 fungal isolates, of which 20 inhibited spore germination. Heat-treated culture filtrates of these isolates were classified into 3 groups according to biological activity. Blast lesion formation by M. oryzae was significantly inhibited by pretreatment with culture filtrates from 4 fungal isolates. ITS region sequence analysis indicated that these?isolates shared similarities with species of the genera Annulohypoxylon, Nigrospora, and Penicillium. Studies of symbiotic and parasitic fungi from wild mushrooms may yield potential control agents for plant diseases such as the rice blast disease.展开更多
Spore germination and appressorium formation of Magnaporthe oryzae spores was completely suppressed by an ethyl acetate extract of the culture filtrate from the H921 isolate (H921-EAE-CF). Production of antifungal sub...Spore germination and appressorium formation of Magnaporthe oryzae spores was completely suppressed by an ethyl acetate extract of the culture filtrate from the H921 isolate (H921-EAE-CF). Production of antifungal substance(s) in the H921-EAE-CF began to increase up to 3 days after isolate H921 incubation. Furthermore, heat treatment (105°C or 121°C) of H921-EAE-CF did not alter its inhibitory effect on M. oryzae spore germination compared to non-heat-treated H921-EAE-CF. Blast lesion formation inhibition by H921-EAE-CF was dose-dependent. Internal transcribed spacer (ITS) region sequence analysis indicated that this isolate shared similarities with species of the genera Trichoderma. This study suggests that H921-EAE-CF contains some antifungal substances that could be promising candidates for control of rice blast disease.展开更多
Microorganism isolates (n = 49) were obtained from the soil samples collected from field in Gotsu city (Kawahira), Shimane. Isolate GT2-E culture inhibited the growth of Xanthomonas oryzae pv. oryzae in disk diffusion...Microorganism isolates (n = 49) were obtained from the soil samples collected from field in Gotsu city (Kawahira), Shimane. Isolate GT2-E culture inhibited the growth of Xanthomonas oryzae pv. oryzae in disk diffusion method. Rice bacterial leaf blight was suppressed by GT2-E culture in the pre- and post-treated rice leaves. Sequence analysis of 16S rDNA region of the GT2-E isolate indicated that it shared 99% similarity with Paenibacillus polymyxa. The growth of GT2-E on LB medium was observed at 15°C, 28°C, 37°C, and 45°C, but not at 4°C. GT2-E isolate could be grown even in the presence of agrochemicals (Amister, Blasin and Kasumin). Furthermore, the growth of X. oryzae pv. oryzae was inhibited by the culture filtrate of GT2-E isolate in disk diffusion method. However, the inhibitory activity of the culture filtrate was heat-unstable. This result suggested that GT2-E isolate can produce heat-unstable inhibitory compound(s). In conclusion, GT2-E isolate might contribute to the development of a new bactericide and biological agent against rice bacterial leaf blight.展开更多
文摘Familial pancreatic cancer (FPC) is broadly defined as two first-degree-relatives with pancreatic cancer (PC) and accounts for 4%-10% of PC. Several genetic syndromes, including Peutz-Jeghers syndrome, hereditary pancreatitis, hereditary breast-ovarian cancer syndrome(HBOC), Lynch syndrome, and familial adenomatous polyposis (FAP), also have increased risks of PC, but the narrowest definition of FPC excludes these known syndromes. When compared with other familial tumors, proven genetic alterations are limited to a small proportion (<20%) and the familial aggregation is usually modest. However, an ethnic deviation (Ashkenazi Jewish>Caucasian) and a younger onset are common also in FPC. In European countries, "anticipation" is reported in FPC families, as with other hereditary syndromes; a trend toward younger age and worse prognosis is recognized in the late years. The resected pancreases of FPC kindred often show multiple pancreatic intraepithelial neoplasia (Pan IN) foci, with various K-ras mutations, similar to colorectal polyposis seen in the FAP patients. As with HBOC patients, a patient who is a BRCA mutation carrier with unresectable pancreatic cancer (accounting for 0%-19% of FPC patients) demonstrated better outcome following platinum and Poly (ADP-ribose) polymerase inhibitor treatment. Western countries have established FPC registries since the 1990 s and several surveillance projects for highrisk individuals are now ongoing to detect early PCs. Improvement in lifestyle habits, including non-smoking, is recommended for individuals at risk. In Japan, the FPC study group was initiated in 2013 and the Japanese FPC registry was established in 2014 by the Japan Pancreas Society.
文摘An isolate GT4028 was obtained from soil samples collected from a field in Gotsu city (Kawahira), Shimane. The use of a culture suspension and culture filtrate of this isolate significantly suppressed the spore germination in Magnaporthe oryzae. The inhibitory activity of the culture filtrate was heat-stable. The formation of rice blast lesions by M. oryzae was significantly suppressed in the presence of the culture suspension of isolate GT4028. Furthermore, mycelial growth of some plant pathogenic fungi was inhibited by the isolate in a dual culture assay. Sequence analysis of 16S rDNA region of the isolate indicated that it shared similarities with species of the genus Burkholderia. Also, isolate GT4028 could be grown even in the presence of fungicides (Blastin, Kasugamycin, and Amistar) that act against M. oryzae. These results suggest that isolate GT4028 might be a potential control agent for plant protection against diseases, such as rice blast disease.
文摘Bipolaris oryzae is the causal agent of brown leaf spot disease in rice, and its asexual spore (conidium) formation is known to be induced by near-ultraviolet (NUV) irradiation. In order to reveal the photomorphogenic response and to identify new genes upregulated by NUV irradiation, suppression subtractive hybridization (SSH) was carried out in B. oryzae. To confirm the differential gene expression in NUV-irradiated mycelia, quantitative real-time PCR (qRT-PCR) analysis was performed among 301 genes arbitrarily chosen from 1170 cDNA clones. The expression of 46 genes (named NUV01 to NUV46) was found to be significantly enhanced (>4-fold) by NUV irradiation. Sequence analysis revealed that 23 out of the 46 sequences (50%) showed significant matches to known fungal genes. The 46 genes were categorized as either BLR1-dependent or BLR1-independent expression groups using the BLR1-deficient mutant, which presumably lacks the blue/UVA-absorbing photoreceptor. This finding demonstrates that NUV irradiation can induce gene regulation, and that this response may be mediated by both a blue/UVA-absorbing photoreceptor and an as-yet-unidentified photoreceptor in B. oryzae.
文摘Bipolaris oryzae is the causal agent of brown spot disease in rice and produces the dark pigment melanin. We isolated and characterized T4HR1 gene encoding 1,3,6,8-tetrahydroxynaphthalene (1,3,6,8-THN) reductase, which converted 1,3,6,8-THN to scytalone in the melanin biosynthesis from B. oryzae. A sequence analysis showed that the T4HR1 gene encoded a putative protein of 268 amino acids showing 50% - 99% sequence identity to other fungal 1,3,6,8-THN reductases. Targeted disruption of the T4HR1 gene showed a different phenotype of mycelial color due to an accumulation of shunt products compared to those of wild-type on PDA plates using tricyclazole as a melanin biosynthesis inhibitor. A quantitative real-time PCR analysis showed that the expression of T4HR1 transcripts was enhanced by near-ultraviolet (NUV) irradiation and regulated by transcriptional factor BMR1, similar to three other melanin biosynthesis genes (polyketide synthase gene [PKS1], scytalone dehydratase gene [SCD1], and 1,3,8-THN reductase gene [THR1]) in the melanin biosynthesis of B. oryzae. These results suggested that common transcriptional mechanisms could regulate the enhanced gene expression of these melanin biosynthesis genes by NUV irradiation in B. oryzae.
文摘A specific and sensitive polymerase chain reaction (PCR) assay based on the internal transcribed spacer (ITS) region of rDNA sequences was developed to detect endophytic and phytopathogenic fungi from needles of the Japanese black pine, Pinus thunbergii. Sequences of the ITS regions of Lophodermium conigenum, Lecanosticta acicola, Pestalotiopsis neglecta, Rhizosphaera kalkhoffii, and Septorioides pini-thunbergii were compared, and each specific primer pair for these species was designed. First, the designed primer pairs were tested for their specificity to detect each species. A PCR product was amplified only each combination of species and its specific primer pair, confirming the specificity of the designed primer pairs. These primer pairs were also tested on DNA extracted from the needles of P. thunbergii. The PCR products were amplified not only in needles with lesions but also in healthy needles without symptoms. Furthermore, several endophytic and phytopathogenic fungi could be simultaneously detected from the same region in a needle. The PCR-mediated detection method developed in this study will be a valuable tool for the detection of the endophytic and phytopathogenic fungi, not only as a rapid diagnostic tool for early detection but also for monitoring variations in both the quality and quantity of the endophytic and phytopathogenic fungi in needles in Japanese black pines.
文摘Fungal strains isolated from the fruiting bodies of wild mushrooms were evaluated for fungicidal activity against Magnaporthe oryzae, the causal agent of the rice blast disease. Fungal isolates (n = 105) were obtained from 46 samples of wild mushrooms. Infection behaviors of M. oryzae were assessed in the presence of culture filtrates from 90 fungal isolates, of which 20 inhibited spore germination. Heat-treated culture filtrates of these isolates were classified into 3 groups according to biological activity. Blast lesion formation by M. oryzae was significantly inhibited by pretreatment with culture filtrates from 4 fungal isolates. ITS region sequence analysis indicated that these?isolates shared similarities with species of the genera Annulohypoxylon, Nigrospora, and Penicillium. Studies of symbiotic and parasitic fungi from wild mushrooms may yield potential control agents for plant diseases such as the rice blast disease.
文摘Spore germination and appressorium formation of Magnaporthe oryzae spores was completely suppressed by an ethyl acetate extract of the culture filtrate from the H921 isolate (H921-EAE-CF). Production of antifungal substance(s) in the H921-EAE-CF began to increase up to 3 days after isolate H921 incubation. Furthermore, heat treatment (105°C or 121°C) of H921-EAE-CF did not alter its inhibitory effect on M. oryzae spore germination compared to non-heat-treated H921-EAE-CF. Blast lesion formation inhibition by H921-EAE-CF was dose-dependent. Internal transcribed spacer (ITS) region sequence analysis indicated that this isolate shared similarities with species of the genera Trichoderma. This study suggests that H921-EAE-CF contains some antifungal substances that could be promising candidates for control of rice blast disease.
文摘Microorganism isolates (n = 49) were obtained from the soil samples collected from field in Gotsu city (Kawahira), Shimane. Isolate GT2-E culture inhibited the growth of Xanthomonas oryzae pv. oryzae in disk diffusion method. Rice bacterial leaf blight was suppressed by GT2-E culture in the pre- and post-treated rice leaves. Sequence analysis of 16S rDNA region of the GT2-E isolate indicated that it shared 99% similarity with Paenibacillus polymyxa. The growth of GT2-E on LB medium was observed at 15°C, 28°C, 37°C, and 45°C, but not at 4°C. GT2-E isolate could be grown even in the presence of agrochemicals (Amister, Blasin and Kasumin). Furthermore, the growth of X. oryzae pv. oryzae was inhibited by the culture filtrate of GT2-E isolate in disk diffusion method. However, the inhibitory activity of the culture filtrate was heat-unstable. This result suggested that GT2-E isolate can produce heat-unstable inhibitory compound(s). In conclusion, GT2-E isolate might contribute to the development of a new bactericide and biological agent against rice bacterial leaf blight.
