36 results on '"Katsunori Murota"'
Search Results
2. Determining vector competence of Aedes aegypti from Ghana in transmitting dengue virus serotypes 1 and 2
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Michael Amoa-Bosompem, Daisuke Kobayashi, Kentaro Itokawa, Katsunori Murota, Astri Nur Faizah, Faustus Akankperiwen Azerigyik, Takaya Hayashi, Mitsuko Ohashi, Joseph H. Kofi Bonney, Samuel Dadzie, Cuong Chi Tran, Phong Vu Tran, Ryosuke Fujita, Yoshihide Maekawa, Shinji Kasai, Shoji Yamaoka, Nobuo Ohta, Kyoko Sawabe, Shiroh Iwanaga, and Haruhiko Isawa
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Aedes aegypti ,Vector competence ,Dengue virus ,Susceptibility ,Ghana ,West Africa ,Infectious and parasitic diseases ,RC109-216 - Abstract
Abstract Background Dengue virus (DENV) is a mosquito-borne arbovirus transmitted by Aedes mosquitoes, but is not endemic in all areas where this vector is found. For example, the relatively sparse distribution of cases in West Africa is generally attributed to the refractory nature of West African Aedes aegypti (Ae. aegypti) to DENV infection, and particularly the forest-dwelling Ae. aegypti formosus. However, recent studies have shown these mosquitoes to be competent vectors within some West African countries that have suffered outbreaks in the past, such as Senegal. There is however little information on the vector competence of the Ae. aegypti in West African countries such as Ghana with no reported outbreaks. Methods This study examined the vector competence of 4 Ae. aegypti colonies from urban, semi-urban, and two rural locations in Ghana in transmitting DENV serotypes 1 and 2, using a single colony from Vietnam as control. Midgut infection and virus dissemination were determined by quantitative reverse transcription polymerase chain reaction (qRT-PCR), while the presence and concentration of DENV in the saliva of infectious mosquitoes was determined by the focus forming assay. Results There were significant differences in the colonies’ susceptibility to virus infection, dissemination, and transmission. All examined Ghanaian mosquitoes were refractory to infection by DENV serotype 2, while some colonies exhibited potential to transmit DENV serotype 1. None of the tested colonies were as competent as the control group colony. Conclusions These findings give insight into the possible risk of outbreaks, particularly in the urban areas in the south of Ghana, and highlight the need for continuous surveillance to determine the transmission status and outbreak risk. This study also highlights the need to prevent importation of different DENV strains and potential invasion of new highly vector-competent Ae. aegypti strains, particularly around the ports of entry. Graphic Abstract
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- 2021
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3. Endemic and Emerging Arboviruses in Domestic Ruminants in East Asia
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Tohru Yanase, Katsunori Murota, and Yoko Hayama
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arthropod-borne virus ,cattle ,Culicoides ,mosquito ,orbivirus ,orthobunyavirus ,Veterinary medicine ,SF600-1100 - Abstract
Epizootic congenital abnormalities caused by Akabane, Aino, and Chuzan viruses have damaged the reproduction of domestic ruminants in East Asia for many years. In the past, large outbreaks of febrile illness related to bovine ephemeral fever and Ibaraki viruses severely affected the cattle industry in that region. In recent years, vaccines against these viruses have reduced the occurrence of diseases, although the viruses are still circulating and have occasionally caused sporadic and small-scaled epidemics. Over a long-term monitoring period, many arboviruses other than the above-mentioned viruses have been isolated from cattle and Culicoides biting midges in Japan. Several novel arboviruses that may infect ruminants (e.g., mosquito- and tick-borne arboviruses) were recently reported in mainland China based on extensive surveillance. It is noteworthy that some are suspected of being associated with cattle diseases. Malformed calves exposed to an intrauterine infection with orthobunyaviruses (e.g., Peaton and Shamonda viruses) have been observed. Epizootic hemorrhagic disease virus serotype 6 caused a sudden outbreak of hemorrhagic disease in cattle in Japan. Unfortunately, the pathogenicity of many other viruses in ruminants has been uncertain, although these viruses potentially affect livestock production. As global transportation grows, the risk of an accidental incursion of arboviruses is likely to increase in previously non-endemic areas. Global warming will also certainly affect the distribution and active period of vectors, and thus the range of virus spreads will expand to higher-latitude regions. To prevent anticipated damages to the livestock industry, the monitoring system for arboviral circulation and incursion should be strengthened; moreover, the sharing of information and preventive strategies will be essential in East Asia.
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- 2020
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4. Deciphering the Virome of Culex vishnui Subgroup Mosquitoes, the Major Vectors of Japanese Encephalitis, in Japan
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Astri Nur Faizah, Daisuke Kobayashi, Haruhiko Isawa, Michael Amoa-Bosompem, Katsunori Murota, Yukiko Higa, Kyoko Futami, Satoshi Shimada, Kyeong Soon Kim, Kentaro Itokawa, Mamoru Watanabe, Yoshio Tsuda, Noboru Minakawa, Kozue Miura, Kazuhiro Hirayama, and Kyoko Sawabe
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virome ,culex tritaeniorhynchus ,japanese encephalitis virus ,flavivirus ,metagenomics ,insect-specific virus ,arbovirus ,culex vishnui subgroup ,Microbiology ,QR1-502 - Abstract
Japanese encephalitis (JE) remains a public health concern in several countries, and the Culex mosquito plays a central role in its transmission cycle. Culex mosquitoes harbor a wide range of viruses, including insect-specific viruses (ISVs), and can transmit a variety of arthropod-borne viruses (arboviruses) that cause human and animal diseases. The current trend of studies displays enhanced efforts to characterize the mosquito virome through bulk RNA sequencing due to possible arbovirus−ISV interactions; however, the extent of viral diversity in the mosquito taxon is still poorly understood, particularly in some disease vectors. In this study, arboviral screening and RNA virome analysis of Culex tritaeniorhynchus and C. pseudovishnui, which are part of the Culex vishnui subgroup mosquitoes, were performed. Results from these two mosquito species, known as the major vectors of JE virus (JEV) in Asia, collected in three prefectures in Japan were also compared with the sympatric species C. inatomii. A total of 27 viruses, including JEV, were detected from these Culex mosquitoes. Molecular and phylogenetic analyses of the detected viruses classified 15 of the 27 viruses as novel species, notably belonging to the Flaviviridae, Rhabdoviridae, Totiviridae, and Iflaviridae families. The successful isolation of JEV genotype I confirmed its continuous presence in Japan, suggesting the need for periodic surveillance. Aside from JEV, this study has also reported the diversity of the RNA virome of disease vectors and broadened the knowledge on mosquito virome profiles containing both arbovirus and ISV. Mosquito taxon seemed to contribute largely to the virome structure (e.g., virome composition, diversity, and abundance) as opposed to the geographical location of the mosquito species. This study therefore offers notable insights into the ecology and evolution of each identified virus and viral family. To the authors’ knowledge, this is the first study to characterize the viromes of the major JE vectors in Japan.
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- 2020
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5. Persistent viruses in mosquito cultured cell line suppress multiplication of flaviviruses
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Ryosuke Fujita, Fumihiro Kato, Daisuke Kobayashi, Katsunori Murota, Tomohiko Takasaki, Shigeru Tajima, Chang-Kweng Lim, Masayuki Saijo, Haruhiko Isawa, and Kyoko Sawabe
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Virology ,Molecular biology ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
In the growth kinetics analysis of flaviviruses in Aedes albopictus C6/36 cell lines obtained from the Japanese Collection of Research Bioresources (JCRB) Cell Bank and the European Collection of Authenticated Cell Culture (ECACC), these two cells line showed different viral susceptibility for Zika virus (ZIKV), Dengue virus (DENV), and Japanese encephalitis virus (JEV). Next-generation sequencing (NGS) analysis revealed that the C6/36 JCRB strain was persistently infected with two viruses without showing any cytopathic effects. The complete sequence analysis demonstrated that the one virus was Menghai rhabdovirus (MERV), which has been found from Aedes albopictus mosquito. The other virus was a novel virus, designated as Shinobi tetravirus (SHTV). Interestingly, the viral susceptibility of these two strains was almost even for Sindbis virus and Getah virus. We cloned SHTV and MERV from JCRB C6/36 cell line and then re-infected them into another C6/36 cell line, resulting in the reproduction of persistent infection with each virus. ZIKV growth was suppressed in SHTV and/or MERV re-infected C6/36 cells also. To our knowledge, this is the first demonstration that persistent infection with rhabdovirus and/or permutotetravirus suppressed flavivirus replication in mosquito cells.
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- 2018
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6. Entomological Assessment of the Status and Risk of Mosquito-borne Arboviral Transmission in Ghana
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Michael Amoa-Bosompem, Daisuke Kobayashi, Katsunori Murota, Astri Nur Faizah, Kentaro Itokawa, Ryosuke Fujita, Joseph Harold Nyarko Osei, Esinam Agbosu, Deborah Pratt, Shohei Kimura, Kofi Dadzie Kwofie, Mitsuko Ohashi, Joseph H. Kofi Bonney, Samuel Dadzie, Toshinori Sasaki, Nobuo Ohta, Haruhiko Isawa, Kyoko Sawabe, and Shiroh Iwanaga
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aedes aegypti ,culex spp. ,cryptic species ,dengue virus ,mosquito virome ,insect-specific virus ,totivirus ,ghana ,virus-virus interaction ,Microbiology ,QR1-502 - Abstract
Entomological surveillance is one of the tools used in monitoring and controlling vector-borne diseases. However, the use of entomological surveillance for arboviral infection vector control is often dependent on finding infected individuals. Although this method may suffice in highly endemic areas, it is not as effective in controlling the spread of diseases in low endemic and non-endemic areas. In this study, we examined the efficiency of using entomological markers to assess the status and risk of arbovirus infection in Ghana, which is considered a non-endemic country, by combining mosquito surveillance with virus isolation and detection. This study reports the presence of cryptic species of mosquitoes in Ghana, demonstrating the need to combine morphological identification and molecular techniques in mosquito surveillance. Furthermore, although no medically important viruses were detected, the importance of insect-specific viruses in understanding virus evolution and arbovirus transmission is discussed. This study reports the first mutualistic relationship between dengue virus and the double-stranded RNA Aedes aegypti totivirus. Finally, this study discusses the complexity of the virome of Aedes and Culex mosquitoes and its implication for arbovirus transmission.
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- 2020
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7. Correction to: Whole‑genome sequence analysis of a novel orthobunyavirus isolated in Japan in the 1980s
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Tohru Yanase, Katsunori Murota, and Yuto Suda
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Virology ,General Medicine - Published
- 2023
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8. Whole-genome sequence analysis of a novel orthobunyavirus isolated in Japan in the 1980s
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Tohru Yanase, Katsunori Murota, and Yuto Suda
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Virology ,General Medicine - Published
- 2023
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9. Discovery of super–insecticide-resistant dengue mosquitoes in Asia: Threats of concomitant knockdown resistance mutations
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Shinji Kasai, Kentaro Itokawa, Nozomi Uemura, Aki Takaoka, Shogo Furutani, Yoshihide Maekawa, Daisuke Kobayashi, Nozomi Imanishi-Kobayashi, Michael Amoa-Bosompem, Katsunori Murota, Yukiko Higa, Hitoshi Kawada, Noboru Minakawa, Tran Chi Cuong, Nguyen Thi Yen, Tran Vu Phong, Sath Keo, Kroesna Kang, Kozue Miura, Lee Ching Ng, Hwa-Jen Teng, Samuel Dadzie, Sri Subekti, Kris Cahyo Mulyatno, Kyoko Sawabe, Takashi Tomita, and Osamu Komagata
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Insecticide Resistance ,Dengue ,Insecticides ,Asia ,Multidisciplinary ,Aedes ,Pyrethrins ,Mutation ,Animals ,Communicable Diseases - Abstract
Aedes aegypti (Linnaeus, 1762) is the main mosquito vector for dengue and other arboviral infectious diseases. Control of this important vector highly relies on the use of insecticides, especially pyrethroids. The high frequency (>78%) of the L982W substitution was detected at the target site of the pyrethroid insecticide, the voltage-gated sodium channel (Vgsc) of A. aegypti collected from Vietnam and Cambodia. Alleles having concomitant mutations L982W + F1534C and V1016G + F1534C were also confirmed in both countries, and their frequency was high (>90%) in Phnom Penh, Cambodia. Strains having these alleles exhibited substantially higher levels of pyrethroid resistance than any other field population ever reported. The L982W substitution has never been detected in any country of the Indochina Peninsula except Vietnam and Cambodia, but it may be spreading to other areas of Asia, which can cause an unprecedentedly serious threat to the control of dengue fever as well as other Aedes -borne infectious diseases.
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- 2022
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10. Isolation of Culicoides- and Mosquito-Borne Orbiviruses in the Southwestern Islands of Japan Between 2014 and 2019
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Hiroaki Shirafuji, Katsunori Murota, Yuji Mekaru, Keiko Ishii, Miho Araki, Haruhiko Isawa, Yuto Suda, Tohru Yanase, and Daisuke Kobayashi
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Serotype ,Orbivirus ,biology ,viruses ,Epizootic hemorrhagic disease virus ,biology.organism_classification ,Culicoides ,medicine.disease ,Microbiology ,Genetic analysis ,Virology ,Arbovirus ,Orthobunyavirus ,Virus ,Infectious Diseases ,medicine - Abstract
The circulation of arboviruses in livestock ruminants has often gone unrecognized owing to the fact that a significant percentage of arboviruses probably induce subclinical infections and/or negligible symptoms in infected animals. To determine the current situation of arbovirus circulation in the Yaeyama Islands, attempts to isolate viruses from bovine blood samples collected between 2014 and 2019 have been made. In total, 308 blood samples were collected during the study period, and 43 of them induced cytopathic effects (CPEs) in cell cultures. The identification of the CPE agents was performed by reported RT-PCR assays and a high-throughput analysis with a next-generation sequencing platform. The obtained viruses consisted of an orthobunyavirus (Peaton virus), Culicoides-borne orbiviruses (bluetongue virus serotypes 12 and 16, epizootic hemorrhagic disease virus [EHDV] serotypes 5, 6, and 7, D'Aguilar virus, and Bunyip Creek virus), and potential mosquito-borne orbiviruses (Yunnan orbivirus, Guangxi orbivirus, and Yonaguni orbivirus). Most of the orbiviruses were recovered from washed blood cells with mosquito cell cultures, suggesting that this combination was more efficient than other combinations such as plasma/blood cells and hamster cell lines. This marked the first time that the isolation of EHDV serotypes 5 and 6 and three potential mosquito-borne orbiviruses was recorded in Japan, showing a greater variety of orbiviruses on the islands than previously known. Genetic analysis of the isolated orbiviruses suggested that the Yaeyama Islands and its neighboring regions were epidemiologically related. Some of the viruses, especially the potential mosquito-borne orbiviruses, were isolated during several consecutive years, indicating their establishment on the islands.
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- 2021
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11. RNA virome analysis of hematophagous Chironomoidea flies (Diptera: Ceratopogonidae and Simuliidae) collected in Tokyo, Japan
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Katsunori Murota, Michael Amoa-Bosompem, Astri Nur Faizah, Daisuke Kobayashi, Yukiko Higa, Kyoko Sawabe, Haruhiko Isawa, Yoshio Tsuda, and Toshihiko Hayashi
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biology ,Ceratopogonidae ,Chironomoidea ,Biting midge ,RNA ,Zoology ,Human virome ,biology.organism_classification ,Black fly - Published
- 2020
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12. Identification and characterization of a novel orbivirus, Yonaguni orbivirus, isolated from cattle on the westernmost island of Japan
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Katsunori Murota, Keiko Ishii, Haruhiko Isawa, Moemi Suzuki, Shogo Tanaka, Tohru Yanase, Daisuke Kobayashi, Hiroaki Shirafuji, Yuto Suda, and Yoshito Katagiri
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Orbivirus ,biology ,Nucleic acid sequence ,Zoology ,Family Reoviridae ,Genetic relationship ,Genome, Viral ,Sequence Analysis, DNA ,General Medicine ,biology.organism_classification ,Genome ,Virology ,Reoviridae Infections ,Open Reading Frames ,Viral Proteins ,Culicidae ,Japan ,Genus Orbivirus ,Bovine blood ,Animals ,Coding region ,Cattle ,Phylogeny - Abstract
A novel orbivirus (genus Orbivirus, family Reoviridae), designated Yonaguni orbivirus (YONOV), was isolated from bovine blood collected on a subtropical island of Japan in 2015. The YONOV genome (20,054 nucleotides in total) has a coding arrangement similar to those of mosquito-borne orbiviruses. YONOV has a close genetic relationship to mosquito-borne orbiviruses, especially to Mobuck virus (MBV), which was isolated in North America. However, YONOV and MBV share less than 74% nucleotide sequence identity in the major subcore protein (T2) coding sequence, which satisfies the criterion for species demarcation. It is still uncertain whether YONOV should be assigned to a novel species in the genus Orbivirus.
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- 2020
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13. Emergence of hyper insecticide-resistant dengue vectors in Indochina Peninsula: threats of concomitant knockdown resistance mutations
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Shinji Kasai, Kentaro Itokawa, Nozomi Uemura, Aki Takaoka, Shogo Furutani, Yoshihide Maekawa, Daisuke Kobayashi, Nozomi Imanishi-Kobayashi, Michael Amoa-Bosompem, Katsunori Murota, Yukiko Higa, Hitoshi Kawada, Noboru Minakawa, Tran Chi Cuong, Nguyen Thi Yen, Tran Vu Phong, Sath Keo, Kroesna Kang, Kozue Miura, Lee Ching Ng, Hwa-Jen Teng, Samuel Dadzie, Sri Subekti, Kris Cahyo Mulyatno, Kyoko Sawabe, Takashi Tomita, and Osamu Komagata
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parasitic diseases - Abstract
Aedes aegypti(Linnaeus, 1762) is the main mosquito vector for dengue and other arboviral infectious diseases. Control of this important vector highly relies on the use of insecticides, especially pyrethroids. Nevertheless, the development of pyrethroid resistance is a major obstacle to mosquito/disease control worldwide. Here, we focused on the mutations in the target site of pyrethroid insecticides, voltage-sensitive sodium channel (Vssc), and found thatAe. aegypticollected from Vietnam has the L982W allele in theVsscat a high frequency (>79%). L982W mutation is located in the highly conserved region ofVsscthat is associated with sodium–ion selectivity and permeation rate. Strains having the L982W allele showed similar or even higher levels of resistance to pyrethroids than those having V1016G, a typical knockdown resistance allele in Asia. Furthermore, concomitant mutations L982W+F1534C and V1016G+F1534C were confirmed, and strains having these multipleVsscmutations exhibited incomparably higher levels of pyrethroid resistance than any other field population ever reported. Molecular modeling analysis confirmed that these concomitant mutant alleles could interfere with approaching pyrethroid toVssc. Remarkably, >90% ofVsscofAe. aegyptiwere occupied by these hyper insecticide-resistant haplotypes in Phnom Penh city, Cambodia. Analysis of wholeVssccoding genes suggested thatVsscs have evolved into stronger resistant forms efficiently through gene recombination events. At this point, L982W has never been detected inVsscofAe. aegyptifrom any other neighboring countries. We strongly emphasize the need to be vigilant about these strong resistance genes spreading to the world through Indochina Peninsula.Significance StatementThe high frequency (>78%) of the L982W allele was detected at the target site of the pyrethroid insecticide, the voltage-sensitive sodium channel (Vssc) ofAedes aegypticollected from Vietnam and Cambodia. Haplotypes having concomitant mutations L982W+F1534C and V1016G+F1534C were also confirmed in both countries, and their frequency was high (>90%) in Phnom Penh, Cambodia. Strains having these haplotypes exhibited substantially higher levels of pyrethroid resistance than any other field population ever reported. The L982W mutation has never been detected in any country of the Indochina Peninsula except Vietnam and Cambodia, but it may be spreading to other areas of Asia, which can cause an unprecedentedly serious threat to the control of dengue fever as well as otherAedes-borne infectious diseases.
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- 2022
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14. Complete genome sequences of Sathuperi and Shamonda viruses isolated in Japan.
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Yuto SUDA, Katsunori MUROTA, and Tohru YANASE
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WHOLE genome sequencing ,CERATOPOGONIDAE ,GENETIC variation ,NUCLEOTIDE sequencing ,SCHMALLENBERG virus ,HUMAN abnormalities ,REOVIRUSES - Abstract
Sathuperi virus (SATV) and Shamonda virus (SHAV) (family Peribunyaviridae, genus Orthobunyavirus, species Schmallenberg orthobunyavirus) have been suggested to cause congenital abnormalities in ruminants. In this study, we determined the complete genome sequences of SATV KSB-6/C/02 and SHAV KSB-2/C/08 strains, which were obtained from Culicoides biting midges in Japan, by next-generation sequencing and Sanger sequencing. The 3ʹ- and 5ʹ-untranslated region sequences of the M segment of SHAV KSB-2/C/08 strains are distinctly different from those of SATV KSB-6/C/02 and Schmallenberg viruses. This study provides the genome characterization of Japanese strains of SATV and SHAV and presented the genetic variation in the untranslated regions of Schmallenberg orthobunyavirus M segments. [ABSTRACT FROM AUTHOR]
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- 2023
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15. Isolation of
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Katsunori, Murota, Keiko, Ishii, Yuji, Mekaru, Miho, Araki, Yuto, Suda, Hiroaki, Shirafuji, Daisuke, Kobayashi, Haruhiko, Isawa, and Tohru, Yanase
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Rodent Diseases ,China ,Culicidae ,Japan ,Cricetinae ,Animals ,Cattle Diseases ,Cattle ,Ceratopogonidae ,Orbivirus ,Reoviridae Infections - Abstract
The circulation of arboviruses in livestock ruminants has often gone unrecognized owing to the fact that a significant percentage of arboviruses probably induce subclinical infections and/or negligible symptoms in infected animals. To determine the current situation of arbovirus circulation in the Yaeyama Islands, attempts to isolate viruses from bovine blood samples collected between 2014 and 2019 have been made. In total, 308 blood samples were collected during the study period, and 43 of them induced cytopathic effects (CPEs) in cell cultures. The identification of the CPE agents was performed by reported RT-PCR assays and a high-throughput analysis with a next-generation sequencing platform. The obtained viruses consisted of an orthobunyavirus (Peaton virus)
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- 2021
16. Determining vector competence of Aedes aegypti from Ghana in transmitting dengue virus serotypes 1 and 2
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Katsunori Murota, Nobuo Ohta, Astri Nur Faizah, Joseph H.K. Bonney, Takaya Hayashi, Ryosuke Fujita, Shiroh Iwanaga, Kyoko Sawabe, Daisuke Kobayashi, Kentaro Itokawa, Michael Amoa-Bosompem, Shinji Kasai, Shoji Yamaoka, Faustus Akankperiwen Azerigyik, Haruhiko Isawa, Yoshihide Maekawa, Mitsuko Ohashi, Samuel K. Dadzie, Cuong Chi Tran, and Phong Vu Tran
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0301 basic medicine ,Serotype ,viruses ,030231 tropical medicine ,Aedes aegypti ,Infectious and parasitic diseases ,RC109-216 ,Mosquito Vectors ,Dengue virus ,Disease Vectors ,medicine.disease_cause ,Serogroup ,Arbovirus ,Ghana ,Dengue ,03 medical and health sciences ,0302 clinical medicine ,Aedes ,parasitic diseases ,West Africa ,medicine ,Animals ,Humans ,Saliva ,biology ,Transmission (medicine) ,Research ,fungi ,Outbreak ,virus diseases ,Dengue Virus ,biology.organism_classification ,medicine.disease ,Virology ,030104 developmental biology ,Infectious Diseases ,Susceptibility ,Vector (epidemiology) ,Parasitology ,Vector competence - Abstract
Background Dengue virus (DENV) is a mosquito-borne arbovirus transmitted by Aedes mosquitoes, but is not endemic in all areas where this vector is found. For example, the relatively sparse distribution of cases in West Africa is generally attributed to the refractory nature of West African Aedes aegypti (Ae. aegypti) to DENV infection, and particularly the forest-dwelling Ae. aegypti formosus. However, recent studies have shown these mosquitoes to be competent vectors within some West African countries that have suffered outbreaks in the past, such as Senegal. There is however little information on the vector competence of the Ae. aegypti in West African countries such as Ghana with no reported outbreaks. Methods This study examined the vector competence of 4 Ae. aegypti colonies from urban, semi-urban, and two rural locations in Ghana in transmitting DENV serotypes 1 and 2, using a single colony from Vietnam as control. Midgut infection and virus dissemination were determined by quantitative reverse transcription polymerase chain reaction (qRT-PCR), while the presence and concentration of DENV in the saliva of infectious mosquitoes was determined by the focus forming assay. Results There were significant differences in the colonies’ susceptibility to virus infection, dissemination, and transmission. All examined Ghanaian mosquitoes were refractory to infection by DENV serotype 2, while some colonies exhibited potential to transmit DENV serotype 1. None of the tested colonies were as competent as the control group colony. Conclusions These findings give insight into the possible risk of outbreaks, particularly in the urban areas in the south of Ghana, and highlight the need for continuous surveillance to determine the transmission status and outbreak risk. This study also highlights the need to prevent importation of different DENV strains and potential invasion of new highly vector-competent Ae. aegypti strains, particularly around the ports of entry. Graphical Abstract
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- 2021
17. Genomic analysis of putative novel serotypes of Tibet orbivirus isolated in Japan
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Tohru Yanase, Hiroaki Shirafuji, Yuto Suda, and Katsunori Murota
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Serotype ,Sequence Homology ,Genomics ,Genome, Viral ,Ceratopogonidae ,Serogroup ,Genome ,Virus ,03 medical and health sciences ,Tibet orbivirus ,Viral Proteins ,Viral genetics ,Japan ,Phylogenetics ,Virology ,Animals ,Orbivirus ,Phylogeny ,030304 developmental biology ,0303 health sciences ,biology ,030306 microbiology ,General Medicine ,Culicoides ,biology.organism_classification ,RNA, Viral - Abstract
Tibet orbivirus (TIBOV) was initially isolated in Tibet in 2009 and subsequently in Guangdong, Hunan, and Yunnan, China. We document the first isolation of TIBOV outside of China: two TIBOV isolates from Culicoides collected in 2009 and 2010 in Kagoshima, Japan. Their complete genome sequences were also determined. Our results suggest that the two virus isolates are of novel serotypes, evident by variability within genome segment 2 encoding VP2. These new putative TIBOV serotypes will help with future virus surveillance and with the evaluation of its potential to cause disease in domestic ruminants.
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- 2020
18. Dengue Virus Infection in Aedes albopictus during the 2014 Autochthonous Dengue Outbreak in Tokyo Metropolis, Japan
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Yoshihide Maekawa, Haruhiko Isawa, Yoshio Tsuda, Kentaro Itokawa, Ryosuke Fujita, Daisuke Kobayashi, Meng Ling Moi, Toshinori Sasaki, Akira Kotaki, Hiroko Ejiri, Mutsuo Kobayashi, Kohei Ogawa, Katsunori Murota, Tomohiko Takasaki, and Kyoko Sawabe
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0301 basic medicine ,Serotype ,Aedes albopictus ,viruses ,030231 tropical medicine ,Genome, Viral ,Aedes aegypti ,Dengue virus ,medicine.disease_cause ,Cell Line ,Disease Outbreaks ,Dengue fever ,Dengue ,03 medical and health sciences ,0302 clinical medicine ,Japan ,Aedes ,Virology ,Genotype ,medicine ,TaqMan ,Animals ,Humans ,biology ,virus diseases ,Articles ,Dengue Virus ,biochemical phenomena, metabolism, and nutrition ,biology.organism_classification ,medicine.disease ,030104 developmental biology ,Infectious Diseases ,Vero cell ,RNA, Viral ,Parasitology - Abstract
In 2014 in Japan, 162 autochthonous dengue cases were reported for the first time in nearly 70 years. Here, we report the results of the detection and isolation of dengue virus (DENV) from mosquitoes collected in Tokyo Metropolis in 2014 and 2015. The phylogenetic relationship among DENV isolates from mosquitoes and from patients based on both the entire envelope gene and whole coding sequences was evaluated. Herein, 2,298 female and 956 male Aedes albopictus mosquitoes were collected at six suspected locations of DENV infection in Tokyo Metropolis from August to October in 2014 and grouped into 124 and 35 pools, respectively, for viral genome detection and DENV isolation. Dengue virus RNA was detected using reverse transcription polymerase chain reaction and TaqMan assays from 49 female pools; 16 isolates were obtained using C6/36 and Vero cells. High minimum infection rates (11.2–66.7) persisted until mid-September. All DENV isolates belonged to the genotype I in serotype 1 (DENV-1), and its sequences demonstrated > 99% homology to the sequence of the DENV isolated from a patient in the vicinity of Tokyo Metropolis in 2014. Therefore, Ae. albopictus was a major DENV vector, and a single DENV-1 strain circulated in Tokyo Metropolis in 2014. Dengue virus was not detected from male mosquitoes in 2014 and wild larvae in April 2015. Thus, the possibility of both vertical transmission and overwintering of DENV was extremely low, even in dengue-epidemic areas. This study reports the first entomological information on a dengue outbreak in a temperate region, where no Aedes aegypti mosquitoes are distributed.
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- 2018
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19. Endemic and Emerging Arboviruses in Domestic Ruminants in East Asia
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Yoko Hayama, Tohru Yanase, and Katsunori Murota
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040301 veterinary sciences ,viruses ,Zoology ,mosquito ,Review ,Cattle Diseases ,orbivirus ,0403 veterinary science ,orthobunyavirus ,03 medical and health sciences ,Bovine ephemeral fever ,medicine ,arthropod-borne virus ,Epizootic ,030304 developmental biology ,0303 health sciences ,Tick-borne disease ,lcsh:Veterinary medicine ,Orbivirus ,General Veterinary ,biology ,Epizootic hemorrhagic disease virus ,Culicoides ,Outbreak ,04 agricultural and veterinary sciences ,medicine.disease ,biology.organism_classification ,cattle ,lcsh:SF600-1100 ,Veterinary Science ,rhabdovirus - Abstract
Epizootic congenital abnormalities caused by Akabane, Aino, and Chuzan viruses have damaged the reproduction of domestic ruminants in East Asia for many years. In the past, large outbreaks of febrile illness related to bovine ephemeral fever and Ibaraki viruses severely affected the cattle industry in that region. In recent years, vaccines against these viruses have reduced the occurrence of diseases, although the viruses are still circulating and have occasionally caused sporadic and small-scaled epidemics. Over a long-term monitoring period, many arboviruses other than the above-mentioned viruses have been isolated from cattle and Culicoides biting midges in Japan. Several novel arboviruses that may infect ruminants (e.g., mosquito- and tick-borne arboviruses) were recently reported in mainland China based on extensive surveillance. It is noteworthy that some are suspected of being associated with cattle diseases. Malformed calves exposed to an intrauterine infection with orthobunyaviruses (e.g., Peaton and Shamonda viruses) have been observed. Epizootic hemorrhagic disease virus serotype 6 caused a sudden outbreak of hemorrhagic disease in cattle in Japan. Unfortunately, the pathogenicity of many other viruses in ruminants has been uncertain, although these viruses potentially affect livestock production. As global transportation grows, the risk of an accidental incursion of arboviruses is likely to increase in previously non-endemic areas. Global warming will also certainly affect the distribution and active period of vectors, and thus the range of virus spreads will expand to higher-latitude regions. To prevent anticipated damages to the livestock industry, the monitoring system for arboviral circulation and incursion should be strengthened; moreover, the sharing of information and preventive strategies will be essential in East Asia.
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- 2019
20. RNA virome analysis of questing ticks from Hokuriku District, Japan, and the evolutionary dynamics of tick-borne phleboviruses
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Osamu Komagata, Michael Amoa-Bosompem, Haruhiko Isawa, Shinichi Noda, Kentaro Itokawa, Mamoru Watanabe, Katsunori Murota, Kyoko Sawabe, Hiroko Ejiri, Astri Nur Faizah, Yoshihide Maekawa, Takeo Yamauchi, Daisuke Kobayashi, and Toshihiko Hayashi
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0301 basic medicine ,Male ,030231 tropical medicine ,Tick ,Microbiology ,Genome ,Virus ,03 medical and health sciences ,0302 clinical medicine ,Ticks ,Japan ,Animals ,RNA Viruses ,Human virome ,Phylogeny ,biology ,Phylogenetic tree ,Base Sequence ,Virome ,RNA ,biology.organism_classification ,Virology ,030104 developmental biology ,Infectious Diseases ,Phlebovirus ,Insect Science ,Larva ,Parasitology ,Female ,Sequence Alignment ,Coltivirus - Abstract
Tick-borne viruses have emerged recently in many parts of the world, and the discoveries of novel tick-borne viruses have been accelerated by the development of high-throughput sequencing technology. In this study, a cost-efficient small benchtop next-generation sequencer, the Illumina MiniSeq, was used for the RNA virome analysis of questing ticks collected from Hokuriku District, Japan, and assessed for their potential utility in a tick-borne virus surveillance system. We detected two phleboviruses [Kabuto Mountain virus (KAMV) and Okutama tick virus (OKTV)], a coltivirus [Tarumizu tick virus (TarTV)], and a novel iflavirus [Hamaphysalis flava iflavirus (HfIFV)] from tick homogenates and/or cell culture supernatants after virus isolation processes. The number of sequence reads from KAMV and TarTV markedly increased when cell culture supernatants were used, indicating a successful isolation of these viruses. In contrast, OKTV and HfIFV were detected only in tick homogenates but not from cell culture supernatants, suggesting a failure to isolate these viruses. Furthermore, we performed genomic and phylogenetic analyzes of these detected viruses. OKTV and some phleboviruses discovered recently by NGS-based methods were probably deficient in the M genome segment, which are herein proposed as M segment-deficient phlebovirus (MdPV). A phylogenetic analysis of phleboviruses, including MdPV, suggested that Uukuniemi and Kaisodi group viruses and kabutoviruses evolved from an ancestral MdPV, which provides insights into the evolutionary dynamics of phleboviruses as emerging pathogens.
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- 2019
21. First detection of a
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Shinji, Kasai, Beniamino, Caputo, Takashi, Tsunoda, Tran Chi, Cuong, Yoshihide, Maekawa, Sai Gek, Lam-Phua, Verena, Pichler, Kentaro, Itokawa, Katsunori, Murota, Osamu, Komagata, Chigusa, Yoshida, Han-Hsuan, Chung, Romeo, Bellini, Yoshio, Tsuda, Hwa-Jen, Teng, José Luiz de Lima, Filho, Luiz Carlos, Alves, Lee Ching, Ng, Noboru, Minakawa, Nguyen Thi, Yen, Tran Vu, Phong, Kyoko, Sawabe, and Takashi, Tomita
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Insecticides ,Genotype ,viruses ,Research ,fungi ,virus diseases ,Mosquito Vectors ,Aedes albopictus ,Polymerase Chain Reaction ,dengue ,pyrethroid resistance ,Insecticide Resistance ,Italy ,Vietnam ,Aedes ,voltage-sensitive sodium channel ,kdr ,parasitic diseases ,Pyrethrins ,V1016G ,Animals ,Humans ,Insect Proteins - Abstract
Introduction Aedes albopictus (Skuse) is an important vector of arboviral diseases, including dengue, chikungunya and Zika virus disease. Monitoring insecticide resistance and mechanisms by which the mosquito develops resistance is crucial to minimise disease transmission. Aim To determine insecticide resistance status and mechanisms in Ae. albopictus from different geographical regions. Methods We sampled 33 populations of Ae. albopictus from Asia, Europe and South America, and tested these for susceptibility to permethrin, a pyrethroid insecticide. In resistant populations, the target site for pyrethroids, a voltage-sensitive sodium channel (Vssc) was genotyped. Three resistant sub-strains, each harbouring a resistance allele homozygously, were established and susceptibilities to three different pyrethroids (with and without a cytochrome P450 inhibitor) were assayed. Results Most populations of Ae. albopictus tested were highly susceptible to permethrin but a few from Italy and Vietnam (4/33), exhibited high-level resistance. Genotyping studies detected a knockdown resistance (kdr) allele V1016G in Vssc for the first time in Ae. albopictus. Two previously reported kdr alleles, F1534C and F1534S, were also detected. The bioassays indicated that the strain homozygous for the V1016G allele showed much greater levels of pyrethroid resistance than other strains harbouring F1534C or F1534S. Conclusion The V1016G allele was detected in bothAsian and Italian Ae. albopictus populations, thus a spread of this allele beyond Italy in Europe cannot be ruled out. This study emphasises the necessity to frequently and regularly monitor the V1016G allele in Ae. albopictus, particularly where this mosquito species is the main vector of arboviruses.
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- 2019
22. First detection of a Vssc allele V1016G conferring a high level of insecticide resistance in Aedes albopictus collected from Europe (Italy) and Asia (Vietnam), 2016. A new emerging threat to controlling arboviral diseases
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Takashi Tsunoda, Lee Ching Ng, Romeo Bellini, Takashi Tomita, Tran Chi Cuong, Sai Gek Lam-Phua, Han-Hsuan Chung, Yoshihide Maekawa, Verena Pichler, Osamu Komagata, Beniamino Caputo, Nguyen Thi Yen, José Luiz de Lima Filho, Chigusa Yoshida, Kentaro Itokawa, Tran Vu Phong, Noboru Minakawa, Kyoko Sawabe, Yoshio Tsuda, Katsunori Murota, Hwa-Jen Teng, Shinji Kasai, and Luiz Carlos Alves
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0301 basic medicine ,Aedes albopictus ,biology ,Epidemiology ,030231 tropical medicine ,Public Health, Environmental and Occupational Health ,Knockdown resistance ,medicine.disease_cause ,medicine.disease ,biology.organism_classification ,Virology ,Dengue fever ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,insecticide resitance ,vector control ,arboviruses ,mosquito borne diseases ,Vector (epidemiology) ,medicine ,Chikungunya ,Allele ,Genotyping ,Permethrin ,medicine.drug - Abstract
Introduction Aedes albopictus (Skuse) is an important vector of arboviral diseases, including dengue, chikungunya and Zika virus disease. Monitoring insecticide resistance and mechanisms by which the mosquito develops resistance is crucial to minimise disease transmission. Aim To determine insecticide resistance status and mechanisms in Ae. albopictus from different geographical regions. Methods We sampled 33 populations of Ae. albopictus from Asia, Europe and South America, and tested these for susceptibility to permethrin, a pyrethroid insecticide. In resistant populations, the target site for pyrethroids, a voltage-sensitive sodium channel (Vssc) was genotyped. Three resistant sub-strains, each harbouring a resistance allele homozygously, were established and susceptibilities to three different pyrethroids (with and without a cytochrome P450 inhibitor) were assayed. Results Most populations of Ae. albopictus tested were highly susceptible to permethrin but a few from Italy and Vietnam (4/33), exhibited high-level resistance. Genotyping studies detected a knockdown resistance (kdr) allele V1016G in Vssc for the first time in Ae. albopictus. Two previously reported kdr alleles, F1534C and F1534S, were also detected. The bioassays indicated that the strain homozygous for the V1016G allele showed much greater levels of pyrethroid resistance than other strains harbouring F1534C or F1534S. Conclusion The V1016G allele was detected in both Asian and Italian Ae. albopictus populations, thus a spread of this allele beyond Italy in Europe cannot be ruled out. This study emphasises the necessity to frequently and regularly monitor the V1016G allele in Ae. albopictus, particularly where this mosquito species is the main vector of arboviruses.
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- 2019
23. Persistent viruses in mosquito cultured cell line suppress multiplication of flaviviruses
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Haruhiko Isawa, Fumihiro Kato, Chang Kweng Lim, Ryosuke Fujita, Tomohiko Takasaki, Daisuke Kobayashi, Masayuki Saijo, Shigeru Tajima, Kyoko Sawabe, and Katsunori Murota
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0301 basic medicine ,Sindbis virus ,Aedes albopictus ,Molecular biology ,viruses ,030106 microbiology ,Dengue virus ,medicine.disease_cause ,Virus ,Article ,Zika virus ,03 medical and health sciences ,Virology ,medicine ,lcsh:Social sciences (General) ,lcsh:Science (General) ,Multidisciplinary ,biology ,Japanese encephalitis ,biology.organism_classification ,medicine.disease ,Flavivirus ,030104 developmental biology ,Novel virus ,lcsh:H1-99 ,lcsh:Q1-390 - Abstract
In the growth kinetics analysis of flaviviruses in Aedes albopictus C6/36 cell lines obtained from the Japanese Collection of Research Bioresources (JCRB) Cell Bank and the European Collection of Authenticated Cell Culture (ECACC), these two cells line showed different viral susceptibility for Zika virus (ZIKV), Dengue virus (DENV), and Japanese encephalitis virus (JEV). Next-generation sequencing (NGS) analysis revealed that the C6/36 JCRB strain was persistently infected with two viruses without showing any cytopathic effects. The complete sequence analysis demonstrated that the one virus was Menghai rhabdovirus (MERV), which has been found from Aedes albopictus mosquito. The other virus was a novel virus, designated as Shinobi tetravirus (SHTV). Interestingly, the viral susceptibility of these two strains was almost even for Sindbis virus and Getah virus. We cloned SHTV and MERV from JCRB C6/36 cell line and then re-infected them into another C6/36 cell line, resulting in the reproduction of persistent infection with each virus. ZIKV growth was suppressed in SHTV and/or MERV re-infected C6/36 cells also. To our knowledge, this is the first demonstration that persistent infection with rhabdovirus and/or permutotetravirus suppressed flavivirus replication in mosquito cells.
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- 2018
24. Characterization of a novel thogotovirus isolated from Amblyomma testudinarium ticks in Ehime, Japan: A significant phylogenetic relationship to Bourbon virus
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Katsunori Murota, Hiroto Shinomiya, Ken Maeda, Tetsuya Mizutani, Ryusei Kuwata, Tomomi Sato, Guillermo Posadas-Herrera, Shohei Minami, Chang Kweng Lim, Hiroko Ejiri, Kyoko Sawabe, Koki Kaku, Yukie Yamaguchi, Daisuke Kobayashi, Masayuki Saijo, Madoka Horiya, Masashi Hattori, Haruhiko Isawa, Miki Kan, Mutsuyo Takayama-Ito, Yukie Katayama, Toshiya Kimura, Hiroshi Shimoda, and Ryosuke Fujita
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0301 basic medicine ,Cancer Research ,Virus Cultivation ,Ixodidae ,viruses ,Sequence Homology ,Tick ,Dhori virus ,Virus Replication ,Virus ,Cell Line ,03 medical and health sciences ,Mice ,Viral Proteins ,Cytopathogenic Effect, Viral ,Japan ,Orthomyxoviridae Infections ,Virology ,Animals ,Cluster Analysis ,Phylogeny ,Virus Release ,Viral matrix protein ,biology ,Amblyomma testudinarium ,Sequence Analysis, DNA ,biology.organism_classification ,Bourbon virus ,Disease Models, Animal ,030104 developmental biology ,Infectious Diseases ,Vero cell ,Thogotovirus - Abstract
The genus Thogotovirus, as represented by Thogoto virus and Dhori virus, comprises a group of arthropod-borne viruses, most members of which are transmitted by ticks. Here we report the genetic and biological characterization of a new thogotovirus, designated Oz virus (OZV), isolated from the hard tick Amblyomma testudinarium in Ehime, Japan. OZV efficiently replicated and induced a cytopathic effect in Vero cells, from which enveloped pleomorphic virus particles were formed by budding. OZV could also replicate in BHK-21 and DH82 cells and caused high mortality in suckling mice after intracerebral inoculation. Phylogenetic analyses of six viral proteins indicated that OZV is clustered with Dhori and related viruses, and is most closely related in glycoprotein (GP) and matrix protein (M) sequences to Bourbon virus, a human-pathogenic thogotovirus discovered recently in the United States. Our findings emphasize the need for understanding the geographic distribution and ecology of OZV and related viruses and for reevaluation of the medical and public health importance of thogotoviruses.
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- 2017
25. Isolation and characterization of Tarumizu tick virus: A new coltivirus from Haemaphysalis flava ticks in Japan
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Mutsuyo Takayama-Ito, Kyoko Sawabe, Ryosuke Fujita, Yukie Katayama, Haruhiko Isawa, Yukie Yamaguchi, Katsunori Murota, Ken Maeda, Shinichi Noda, Mamoru Watanabe, Tetsuya Mizutani, Ryusei Kuwata, Guillermo Posadas-Herrera, Daisuke Kobayashi, Masayuki Saijo, Takeo Yamauchi, Hiroshi Shimoda, Shohei Minami, Madoka Horiya, Chang Kweng Lim, and Hiroko Ejiri
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0301 basic medicine ,Cancer Research ,Ixodidae ,Sequence analysis ,Reoviridae ,Sequence Homology ,Genome, Viral ,Biology ,Tick ,Arbovirus ,Genome ,Virus ,Inclusion Bodies, Viral ,03 medical and health sciences ,Mice ,Capsid ,Japan ,Microscopy, Electron, Transmission ,Virology ,Cricetinae ,medicine ,Animals ,Cells, Cultured ,Coltivirus ,Phylogeny ,Genetics ,Virion ,Sequence Analysis, DNA ,medicine.disease ,biology.organism_classification ,Reoviridae Infections ,030104 developmental biology ,Infectious Diseases ,Novel virus - Abstract
During the course of tick-borne virus surveillance in Japan, three independent isolates of probably the same virus were obtained from three geographically distant populations of the hard tick Haemaphysalis flava. Genome analyses of the three isolates demonstrated that they were closely related but distinct strains of a novel virus, designated Tarumizu tick virus (TarTV), which has a genome of 12 double-stranded RNA segments. The development of the virus-induced cytopathic effects on BHK cells significantly varied according to virus strains. Ten out of 12 segments of TarTV appeared to encode putative orthologs or functional equivalents of viral proteins of Colorado tick fever virus (CTFV) and Eyach virus, suggesting that TarTV is the third member of the genus Coltivirus in the family Reoviridae. This was supported by the facts that the 5'- and 3'-terminal consensus sequences of coltivirus genomes were found also in TarTV genome, and segment 9 of TarTV had sequence and structural features that may mediate a stop codon read-through as observed in that of CTFV. However, segment 7 and 10 of TarTV had no significant sequence similarities to any other proteins of known coltiviruses. Electron microscopic analysis demonstrated that TarTV particle had a non-enveloped bilayer icosahedral structure, and viral inclusion bodies were formed in infected cells. TarTV could infect and replicate in several mammalian cell lines tested, but show no clinical symptoms in intracerebrally inoculated mice. Taken together, our findings provide new insights into genetic diversity and evolution of the genus Coltivirus.
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- 2017
26. Interaction between Cucumber mosaic virus 2b protein and plant catalase induces a specific necrosis in association with proteasome activity
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Chikara Masuta, Minoru Takeshita, Katsunori Murota, and Hanako Shimura
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0106 biological sciences ,0301 basic medicine ,Agroinfiltration ,Proteasome Endopeptidase Complex ,Necrosis ,Immunoprecipitation ,Arabidopsis ,Plant Science ,Biology ,01 natural sciences ,Cucumovirus ,Cucumber mosaic virus ,03 medical and health sciences ,chemistry.chemical_compound ,Gene Knockout Techniques ,Viral Proteins ,MG132 ,medicine ,Plant Diseases ,2b Protein Arabidopsis thaliana ,Arabidopsis Proteins ,Ubiquitin ,Ubiquitin–proteasome ,Wild type ,General Medicine ,Catalase ,Molecular biology ,Plant Leaves ,030104 developmental biology ,chemistry ,Mutation ,Proteolysis ,Proteasome inhibitor ,biology.protein ,Original Article ,medicine.symptom ,Agronomy and Crop Science ,010606 plant biology & botany ,medicine.drug - Abstract
Key message Cucumber mosaic virus (CMV) can induce a specific necrosis on Arabidopsis through the interaction between the CMV 2b protein and host catalase, in which the ubiquitin–proteasome pathway may be involved. Abstract We previously reported that the CMV 2b protein, the viral RNA silencing suppressor, interacted with the H2O2 scavenger catalase (CAT3), leading to necrosis on CMV-inoculated Arabidopsis leaves. We here confirmed that CMV could more abundantly accumulate in the CAT3-knockout mutant (cat3), and that CAT3 makes host plants a little more tolerant to CMV. We also found that the necrosis severity is not simply explained by a high level of H2O2 given by the lack of CAT3, because the recombinant CMV, CMV-N, induced much milder necrosis in cat3 than in the wild type, suggesting some specific mechanism for the necrosis induction. To further characterize the 2b-inducing necrosis in relation to its binding to CAT3, we conducted the agroinfiltration experiments to overexpress CAT3 and 2b in N. benthamiana leaves. The accumulation levels of CAT3 were higher when co-expressed with the CMV-N 2b (N2b) than with CMV-Y 2b (Y2b). We infer that N2b made a more stable complex with CAT3 than Y2b did, and the longevity of the 2b–CAT3 complex seemed to be important to induce necrosis. By immunoprecipitation (IP) with an anti-ubiquitin antibody followed by the detection with anti-CAT3 antibodies, we detected a higher molecular-weight smear and several breakdown products of CAT3 among the IP-proteins. In addition, the proteasome inhibitor MG132 treatment could actually increase the accumulation levels of CAT3. This study suggests that the host proteasome pathway is, at least partially, responsible for the degradation of CAT3, which is manifested in CMV-infected tissues. Electronic supplementary material The online version of this article (doi:10.1007/s00299-016-2055-2) contains supplementary material, which is available to authorized users.
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- 2016
27. The Minimum Open Reading Frame, AUG-Stop, Induces Boron-Dependent Ribosome Stalling and mRNA Degradation
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Kyoko Miwa, Yui Yamashita, Yusuke Yamazumi, Katsunori Murota, Yukako Chiba, Tetsu Akiyama, Satoshi Naito, Mayuki Tanaka, Masami Yokota Hirai, Hitoshi Onouchi, Toru Fujiwara, and Naoyuki Sotta
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0301 basic medicine ,inorganic chemicals ,Five prime untranslated region ,RNA Stability ,Arabidopsis ,Plant Science ,Biology ,Aquaporins ,Ribosome ,03 medical and health sciences ,Open Reading Frames ,Gene Expression Regulation, Plant ,Upstream open reading frame ,Gene expression ,Gene ,Research Articles ,Boron ,Genetics ,Membrane Glycoproteins ,Arabidopsis Proteins ,Translation (biology) ,Cell Biology ,Open reading frame ,030104 developmental biology ,Transcription Factor Gene ,Ribosomes ,Transcription Factors - Abstract
Upstream open reading frames (uORFs) are often translated ahead of the main ORF of a gene and regulate gene expression, sometimes in a condition-dependent manner, but such a role for the minimum uORF (hereafter referred to as AUG-stop) in living organisms is currently unclear. Here, we show that AUG-stop plays an important role in the boron (B)-dependent regulation of NIP5;1, encoding a boric acid channel required for normal growth under low B conditions in Arabidopsis thaliana High B enhanced ribosome stalling at AUG-stop, which was accompanied by the suppression of translation and mRNA degradation. This mRNA degradation was promoted by an upstream conserved sequence present near the 5'-edge of the stalled ribosome. Once ribosomes translate a uORF, reinitiation of translation must take place in order for the downstream ORF to be translated. Our results suggest that reinitiation of translation at the downstream NIP5;1 ORF is enhanced under low B conditions. A genome-wide analysis identified two additional B-responsive genes, SKU5 and the transcription factor gene ABS/NGAL1, which were regulated by B-dependent ribosome stalling through AUG-stop. This regulation was reproduced in both plant and animal transient expression and cell-free translation systems. These findings suggest that B-dependent AUG-stop-mediated regulation is common in eukaryotes.
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- 2016
28. Nascent Peptide-Mediated Translation Elongation Arrest of Arabidopsis thaliana CGS1 mRNA Occurs Autonomously
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Katsunori Murota, Mari Nakamoto, Satoshi Naito, Daisuke Kawasaki, Yoko Nagami-Yamashita, Hitoshi Onouchi, Yuhi Haraguchi, Yukako Chiba, and Azusa Kezuka-Hosomi
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Reticulocytes ,Physiology ,RNA Stability ,Amino Acid Motifs ,Carbon-Oxygen Lyases ,Arabidopsis ,Down-Regulation ,Plant Science ,Ribosome ,Reticulocyte ,Gene Expression Regulation, Plant ,Genes, Reporter ,medicine ,Animals ,Arabidopsis thaliana ,RNA, Messenger ,Luciferases ,Peptide sequence ,Gene ,Messenger RNA ,biology ,Arabidopsis Proteins ,Translation (biology) ,Exons ,Cell Biology ,General Medicine ,biology.organism_classification ,Cystathionine beta synthase ,medicine.anatomical_structure ,Biochemistry ,Protein Biosynthesis ,biology.protein ,Rabbits ,Peptides - Abstract
The Arabidopsis thaliana CGS1 gene encodes cystathionine gamma-synthase, the first committed enzyme of methionine biosynthesis in higher plants. Expression of CGS1 is feedback-regulated at the step of mRNA degradation in response to S-adenosyl-L-methionine (AdoMet). A short stretch of amino acid sequence, termed the MTO1 region, encoded within the first exon of CGS1 itself acts in cis in the regulation. In vitro analyses using wheat germ extract (WGE) revealed that AdoMet induces temporal translation arrest of CGS1 mRNA prior to mRNA degradation. This translational pausing occurs immediately downstream of the MTO1 region and is mediated by the nascent MTO1 peptide. In order to elucidate further the nature of this unique regulatory mechanism, we have examined whether a non-plant system also contains the post-transcriptional regulation activity. Despite the fact that mammals do not carry cystathionine gamma-synthase, AdoMet was able to induce the MTO1 sequence-dependent translation elongation arrest in rabbit reticulocyte lysate (RRL) in a similar manner to that observed in WGE. This result suggests that MTO1 peptide-mediated translation arrest does not require a plant-specific factor and rather most probably occurs via a direct interaction between the nascent MTO1 peptide and the ribosome that has translated it. In contrast, decay intermediates of CGS1 mRNA normally observed upon induction of CGS1 mRNA decay in plant systems were not detected in RRL, raising the possibility that CGS1 mRNA degradation involves a plant-specific mechanism.
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- 2008
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29. Polyamine-responsive ribosomal arrest at the stop codon of an upstream open reading frame of the AdoMetDC1 gene triggers nonsense-mediated mRNA decay in Arabidopsis thaliana
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Katsunori Murota, Satoshi Naito, Karin Murakami, Mariko Takemoto, Naoko Uchiyama-Kadokura, Naoto Koyanagi, and Hitoshi Onouchi
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Untranslated region ,Adenosylmethionine Decarboxylase ,Physiology ,Nonsense-mediated decay ,Arabidopsis ,Plant Science ,Biology ,Ribosome ,Open Reading Frames ,Gene Expression Regulation, Plant ,Genes, Reporter ,Untranslated Regions ,Upstream open reading frame ,Translational regulation ,Polyamines ,Coding region ,Arabidopsis Proteins ,Cell Biology ,General Medicine ,Plants, Genetically Modified ,Molecular biology ,Stop codon ,Nonsense Mediated mRNA Decay ,Open reading frame ,Codon, Nonsense ,Mutation ,Codon, Terminator ,Ribosomes - Abstract
During mRNA translation, nascent peptides with certain specific sequences cause arrest of ribosomes that have synthesized themselves. In some cases, such ribosomal arrest is coupled with mRNA decay. In yeast, mRNA quality control systems have been shown to be involved in mRNA decay associated with ribosomal arrest. However, a link between ribosomal arrest and mRNA quality control systems has not been found in multicellular organisms. In this study, we aimed to explore the relationship between ribosomal arrest and mRNA decay in plants. For this purpose, we used an upstream open reading frame (uORF) of the Arabidopsis thaliana AdoMetDC1 gene, in which the uORF-encoded peptide is involved in polyamine-responsive translational repression of the main coding sequence. Our in vitro analyses revealed that the AdoMetDC1 uORF-encoded peptide caused ribosomal arrest at the uORF stop codon in response to polyamine. Using transgenic calli harboring an AdoMetDC1 uORF-containing reporter gene, we showed that polyamine promoted mRNA decay in a uORF sequence-dependent manner. These results suggest that the polyamine-responsive ribosomal arrest mediated by the uORF-encoded peptide is coupled with mRNA decay. Our results also showed that the polyamine-responsive acceleration of mRNA decay was compromised by defects in factors that are essential for nonsense-mediated mRNA decay (NMD), an mRNA quality control system that degrades mRNAs with premature stop codons, suggesting that NMD is involved in AdoMetDC1 uORF peptide-mediated mRNA decay. Collectively, these findings suggest that AdoMetDC1 uORF peptide-mediated ribosomal arrest at the uORF stop codon induces NMD.
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- 2014
30. Translation Elongation Arrest Induced by S-Adenosyl-l-Methionine-Sensing Nascent Peptide in Plants
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Satoshi Naito, Yui Yamashita, Katsunori Murota, Hitoshi Onouchi, and Noriyuki Onoue
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chemistry.chemical_classification ,biology ,chemistry ,Arabidopsis ,Gene expression ,Peptide ,Translation (biology) ,Ribosomal RNA ,biology.organism_classification ,Gene ,Ribosome ,In vitro ,Cell biology - Abstract
The CGS1 gene of the model plant Arabidopsis encodes cystathionine-γ-synthase, which catalyzes the first committed step of methionine biosynthesis. CGS1 gene expression is feedback regulated in response to S-adenosyl-l-methionine (AdoMet) by a coupled process of translation arrest and CGS1 mRNA degradation. In vitro translation studies using wheat germ extract revealed that AdoMet induces transient translation elongation arrest at Ser-94, located immediately downstream of the MTO1 region, which is the cis-element for translation arrest. Upon translation arrest, peptidyl-tRNASer resides in the A-site and the ribosome is arrested at the pre-translocation step. The nascent peptide containing the MTO1 region adopts a compact conformation in the arrested ribosome, and the 28S rRNA of the ribosomal exit tunnel region may also undergo conformation changes. This pre-translocation step arrest feature makes the CGS1 system unique among the nascent peptide-mediated ribosome stalling systems.
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- 2014
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31. First detection of a Vssc allele V1016G conferring a high level of insecticide resistance in Aedes albopictus collected from Europe (Italy) and Asia (Vietnam), 2016: a new emerging threat to controlling arboviral diseases.
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Kasal, Shinji, Caputo, Beniamino, Takashi Tsunoda, Chi Cuong, Tran, Yoshihide Maekawa, Sai Gek Lam-Phua, Pichler, Verena, Itokawa, Kentaro, Katsunori Murota, Osamu Komagata, Chigusa Yoshida, Han-Hsuan Chung, Romeo Bellini, Yoshio Tsuda, Hwa-Jen Teng, de Lima Filho, José Luiz, Alves, Luiz Carlos, Lee Ching Ng, Noboru Minakawa, and Nguyen Thi Yen
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- 2019
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32. Dengue Virus Infection in Aedes albopictus during the 2014 Autochthonous Dengue Outbreak in Tokyo Metropolis, Japan.
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Daisuke Kobayashi, Katsunori Murota, Ryosuke Fujita, Kentaro Itokawa, Akira Kotaki, Meng Ling Moi, Hiroko Ejiri, Yoshihide Maekawa, Kohei Ogawa, Yoshio Tsuda, Toshinori Sasaki, Mutsuo Kobayashi, Tomohiko Takasaki, Haruhiko Isawa, and Kyoko Sawabe
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- 2018
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33. Arabidopsis cell-free extract, ACE, a new in vitro translation system derived from Arabidopsis callus cultures
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Masayuki Ishikawa, Katsunori Murota, Keisuke Komoda, Hitoshi Onouchi, Yuka Hagiwara-Komoda, and Satoshi Naito
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RNA Caps ,S-Adenosylmethionine ,Transcription, Genetic ,Physiology ,RNA Stability ,Mutant ,Arabidopsis ,Plant Science ,Cell-free system ,Tissue Culture Techniques ,chemistry.chemical_compound ,Biosynthesis ,Gene Expression Regulation, Plant ,Genes, Reporter ,Protein biosynthesis ,RNA, Messenger ,Post-transcriptional regulation ,Plant Proteins ,Genetics ,biology ,Cell-Free System ,Plant Extracts ,food and beverages ,Cell Biology ,General Medicine ,Exons ,biology.organism_classification ,Cystathionine beta synthase ,Cell biology ,chemistry ,Callus ,Protein Biosynthesis ,Exoribonucleases ,Mutation ,biology.protein - Abstract
The analysis of post-transcriptional regulatory mechanisms in plants has benefited greatly from the use of cell-free extract systems. Arabidopsis as a model system provides extensive genetic resources; however, to date a suitable cell-free translation system from Arabidopsis has not been available. In this study, we devised an Arabidopsis cell-free extract (ACE) to be used for in vitro translation studies. Protoplasts were prepared from callus cultures derived from Arabidopsis seedlings, and cell-free extracts were prepared after evacuolation of the protoplasts by Percoll gradient centrifugation. The new ACE system exhibits translation activity comparable with that of the wheat germ extract system. We demonstrated that ACE prepared from the 5'-3' exoribonuclease-deficient mutant of Arabidopsis, xrn4-5, exhibited increased stability of an uncapped mRNA as compared with that from wild-type Arabidopsis. We applied the ACE system to study post-transcriptional regulation of AtCGS1. AtCGS1 codes for cystathionine γ-synthase (CGS) that catalyzes the first committed step of methionine and S-adenosyl-l-methionine (AdoMet) biosynthesis in plants, and is feedback regulated by mRNA degradation coupled with translation elongation arrest. The ACE system was capable of reproducing translation elongation arrest and subsequent AtCGS1 mRNA degradation that are induced by AdoMet. The ACE system described here can be prepared in a month after seed sowing and will make it possible to study post-transcriptional regulation of plant genes while taking advantage of the genetics of Arabidopsis.
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- 2011
34. Evidence of capsaicin synthase activity of the Pun1-encoded protein and its role as a determinant of capsaicinoid accumulation in pepper
- Author
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Chikara Masuta, Yasuko Togawa, Takeshi Matsumura, Katsunori Murota, Hanako Shimura, Misaki Furuya, and Kana Ogawa
- Subjects
pAMT ,Virus-induced gene silencing ,Pun1 ,Plant Science ,Biology ,Gene product ,chemistry.chemical_compound ,Western blot ,Biosynthesis ,Gene Expression Regulation, Plant ,Gene expression ,medicine ,Pungency ,Plant Proteins ,Regulation of gene expression ,medicine.diagnostic_test ,Protoplasts ,Vanillylamine ,Protoplast assay ,Biochemistry ,chemistry ,Capsaicin ,lipids (amino acids, peptides, and proteins) ,Capsicum ,Research Article - Abstract
Background Capsaicinoids, including capsaicin and its analogs, are responsible for the pungency of pepper (Capsicum species) fruits. Even though capsaicin is familiar and used daily by humans, the genes involved in the capsaicin biosynthesis pathway have not been well characterized. The putative aminotransferase (pAMT) and Pungent gene 1 (Pun1) proteins are believed to catalyze the second to last and the last steps in the pathway, respectively, making the Pun1 protein the putative capsaicin synthase. However, there is no direct evidence that Pun1 has capsaicin synthase activity. Results To verify that the Pun1 protein actually plays a role in capsaicin production, we generated anti-Pun1 antibodies against an Escherichia coli-synthesized Pun1 protein and used them to antagonize endogenous Pun1 activity. To confirm the anti-Pun1 antibodies’ specificity, we targeted Pun1 mRNA using virus-induced gene silencing. In the Pun1-down-regulated placental tissues, the accumulated levels of the Pun1 protein, which was identified on a western blot using the anti-Pun1 antibodies, were reduced, and simultaneously, capsaicin accumulations were reduced in the same tissues. In the de novo capsaicin synthesis in vitro cell-free assay, which uses protoplasts isolated from placental tissues, capsaicin synthesis was inhibited by the addition of anti-Pun1 antibodies. We next analyzed the expression profiles of pAMT and Pun1 in various pepper cultivars and found that high levels of capsaicin accumulation always accompanied high expression levels of both pAMT and Pun1, indicating that both genes are important for capsaicin synthesis. However, comparisons of the accumulated levels of vanillylamine (a precursor of capsaicin) and capsaicin between pungent and nonpungent cultivars revealed that vanillylamine levels in the pungent cultivars were very low, probably owing to its rapid conversion to capsaicin by Pun1 soon after synthesis, and that in nonpungent cultivars, vanillylamine accumulated to quite high levels owing to the lack of Pun1. Conclusions Using a newly developed protoplast-based assay for de novo capsaicin synthesis and the anti-Pun1 antibodies, we successfully demonstrated that the Pun1 gene and its gene product are involved in capsaicin synthesis. The analysis of the vanillylamine accumulation relative to that of capsaicin indicated that Pun1 was the primary determinant of their accumulation levels. Electronic supplementary material The online version of this article (doi:10.1186/s12870-015-0476-7) contains supplementary material, which is available to authorized users.
- Published
- 2015
35. Evidence of capsaicin synthase activity of the Pun1-encoded protein and its role as a determinant of capsaicinoid accumulation in pepper.
- Author
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Kana Ogawa, Katsunori Murota, Hanako Shimura, Misaki Furuya, Yasuko Togawa, Takeshi Matsumura, and Chikara Masuta
- Subjects
- *
CAPSAICIN , *PEPPER research , *PLANT proteins , *PUNGENCY , *GENE silencing - Abstract
Background: Capsaicinoids, including capsaicin and its analogs, are responsible for the pungency of pepper (Capsicum species) fruits. Even though capsaicin is familiar and used daily by humans, the genes involved in the capsaicin biosynthesis pathway have not been well characterized. The putative aminotransferase (pAMT) and Pungent gene 1 (Pun1) proteins are believed to catalyze the second to last and the last steps in the pathway, respectively, making the Pun1 protein the putative capsaicin synthase. However, there is no direct evidence that Pun1 has capsaicin synthase activity. Results: To verify that the Pun1 protein actually plays a role in capsaicin production, we generated anti-Pun1 antibodies against an -synthesized Pun1 protein and used them to antagonize endogenous Pun1 Escherichia coli activity. To confirm the anti-Pun1 antibodies' specificity, we targeted mRNA using virus-induced gene silencing. In Pun1 the -down-regulated placental tissues, the accumulated levels of the Pun1 protein, which was identified on a Pun1 western blot using the anti-Pun1 antibodies, were reduced, and simultaneously, capsaicin accumulations were reduced in the same tissues. In the capsaicin synthesis cell-free assay, which uses protoplasts isolated from de novo in vitro placental tissues, capsaicin synthesis was inhibited by the addition of anti-Pun1 antibodies. We next analyzed the expression profiles of and in various pepper cultivars and found that high levels of capsaicin accumulation pAMT Pun1 always accompanied high expression levels of both and, indicating that both genes are important for pAMT Pun1 capsaicin synthesis. However, comparisons of the accumulated levels of vanillylamine (a precursor of capsaicin) and capsaicin between pungent and nonpungent cultivars revealed that vanillylamine levels in the pungent cultivars were very low, probably owing to its rapid conversion to capsaicin by Pun1 soon after synthesis, and that in nonpungent cultivars, vanillylamine accumulated to quite high levels owing to the lack of Pun1. Conclusions: Using a newly developed protoplast-based assay for capsaicin synthesis and the anti-Pun1 de novo antibodies, we successfully demonstrated that the gene and its gene product are involved in capsaicin Pun1 synthesis. The analysis of the vanillylamine accumulation relative to that of capsaicin indicated that Pun1 was the primary determinant of their accumulation levels. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
36. Nascent Peptide-Mediated Translation Elongation Arrest of Arabidopsis thaliana CGS1 mRNA Occurs Autonomously.
- Author
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Hitoshi Onouchi, Yuhi Haraguchi, Mari Nakamoto, Daisuke Kawasaki, Yoko Nagami-Yamashita, Katsunori Murota, Azusa Kezuka-Hosomi, Yukako Chiba, and Satoshi Naito
- Subjects
MESSENGER RNA ,WHEAT ,ARABIDOPSIS ,METHIONINE - Abstract
The Arabidopsis thaliana CGS1 gene encodes cystathionine γ-synthase, the first committed enzyme of methionine biosynthesis in higher plants. Expression of CGS1 is feedback-regulated at the step of mRNA degradation in response to S-adenosyl-l-methionine (AdoMet). A short stretch of amino acid sequence, termed the MTO1 region, encoded within the first exon of CGS1 itself acts in cis in the regulation. In vitro analyses using wheat germ extract (WGE) revealed that AdoMet induces temporal translation arrest of CGS1 mRNA prior to mRNA degradation. This translational pausing occurs immediately downstream of the MTO1 region and is mediated by the nascent MTO1 peptide. In order to elucidate further the nature of this unique regulatory mechanism, we have examined whether a non-plant system also contains the post-transcriptional regulation activity. Despite the fact that mammals do not carry cystathionine γ-synthase, AdoMet was able to induce the MTO1 sequence-dependent translation elongation arrest in rabbit reticulocyte lysate (RRL) in a similar manner to that observed in WGE. This result suggests that MTO1 peptide-mediated translation arrest does not require a plant-specific factor and rather most probably occurs via a direct interaction between the nascent MTO1 peptide and the ribosome that has translated it. In contrast, decay intermediates of CGS1 mRNA normally observed upon induction of CGS1 mRNA decay in plant systems were not detected in RRL, raising the possibility that CGS1 mRNA degradation involves a plant-specific mechanism. [ABSTRACT FROM AUTHOR]
- Published
- 2008
- Full Text
- View/download PDF
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