This page has only limited features, please log in for full access.

Unclaimed
Michihito Sasaki
Division of Molecular Pathobiology, International Institute for Zoonosis Control, Hokkaido University, Sapporo 001-0020, Japan

Honors and Awards

The user has no records in this section


Career Timeline

The user has no records in this section.


Short Biography

The user biography is not available.
Following
Followers
Co Authors
The list of users this user is following is empty.
Following: 0 users

Feed

Journal article
Published: 24 August 2021 in Viruses
Reads 0
Downloads 0

The interaction of viral nucleic acid with protein factors is a crucial process for initiating viral polymerase-mediated viral genome replication while activating pattern recognition receptor (PRR)-mediated innate immune responses. It has previously been reported that a hydrolysate of Ge-132, 3-(trihydroxygermyl) propanoic acid (THGP), shows a modulatory effect on microbial infections, inflammation, and immune responses. However, the detailed mechanism by which THGP can modify these processes during viral infections remained unknown. Here, we show that THGP can specifically downregulate type I interferon (IFN) production in response to stimulation with a cytosolic RNA sensor RIG-I ligand 5′-triphosphate RNA (3pRNA) but not double-stranded RNA, DNA, or lipopolysaccharide. Consistently, treatment with THGP resulted in the dose-dependent suppression of type I IFN induction upon infections with influenza virus (IAV) and vesicular stomatitis virus, which are known to be mainly sensed by RIG-I. Mechanistically, THGP directly binds to the 5′-triphosphate moiety of viral RNA and competes with RIG-I-mediated recognition. Furthermore, we found that THGP can directly counteract the replication of IAV but not EMCV (encephalitismyocarditis virus), by inhibiting the interaction of viral polymerase with RNA genome. Finally, IAV RNA levels were significantly reduced in the lung tissues of THGP-treated mice when compared with untreated mice. These results suggest a possible therapeutic implication of THGP and show direct antiviral action, together with the suppressive activity of innate inflammation.

ACS Style

Sunanda Baidya; Yoko Nishimoto; Seiichi Sato; Yasuhiro Shimada; Nozomi Sakurai; Hirotaka Nonaka; Koki Noguchi; Mizuki Kido; Satoshi Tadano; Kozo Ishikawa; Kai Li; Aoi Okubo; Taisho Yamada; Yasuko Orba; Michihito Sasaki; Hirofumi Sawa; Hiroko Miyamoto; Ayato Takada; Takashi Nakamura; Akinori Takaoka. Dual Effect of Organogermanium Compound THGP on RIG-I-Mediated Viral Sensing and Viral Replication during Influenza a Virus Infection. Viruses 2021, 13, 1674 .

AMA Style

Sunanda Baidya, Yoko Nishimoto, Seiichi Sato, Yasuhiro Shimada, Nozomi Sakurai, Hirotaka Nonaka, Koki Noguchi, Mizuki Kido, Satoshi Tadano, Kozo Ishikawa, Kai Li, Aoi Okubo, Taisho Yamada, Yasuko Orba, Michihito Sasaki, Hirofumi Sawa, Hiroko Miyamoto, Ayato Takada, Takashi Nakamura, Akinori Takaoka. Dual Effect of Organogermanium Compound THGP on RIG-I-Mediated Viral Sensing and Viral Replication during Influenza a Virus Infection. Viruses. 2021; 13 (9):1674.

Chicago/Turabian Style

Sunanda Baidya; Yoko Nishimoto; Seiichi Sato; Yasuhiro Shimada; Nozomi Sakurai; Hirotaka Nonaka; Koki Noguchi; Mizuki Kido; Satoshi Tadano; Kozo Ishikawa; Kai Li; Aoi Okubo; Taisho Yamada; Yasuko Orba; Michihito Sasaki; Hirofumi Sawa; Hiroko Miyamoto; Ayato Takada; Takashi Nakamura; Akinori Takaoka. 2021. "Dual Effect of Organogermanium Compound THGP on RIG-I-Mediated Viral Sensing and Viral Replication during Influenza a Virus Infection." Viruses 13, no. 9: 1674.

Journal article
Published: 01 July 2021 in Microbiology Resource Announcements
Reads 0
Downloads 0

Pseudomonas aeruginosa causes various opportunistic infections in animals. Here, we report the complete genome sequence of P. aeruginosa strain Pa12, a fluoroquinolone-resistant isolate from a canine skin lesion. To expand the molecular antimicrobial characteristics of the isolate, the whole Pa12 genome was sequenced and assembled via long- and short-read platforms.

ACS Style

Keisuke Nakamura; Jumpei Fujiki; Takaaki Furusawa; Tomohiro Nakamura; Satoshi Gondaira; Michihito Sasaki; Masaru Usui; Hidetoshi Higuchi; Hirofumi Sawa; Yutaka Tamura; Hidetomo Iwano. Complete Genome Sequence of a Veterinary Pseudomonas aeruginosa Isolate, Pa12. Microbiology Resource Announcements 2021, 10, e0039821 .

AMA Style

Keisuke Nakamura, Jumpei Fujiki, Takaaki Furusawa, Tomohiro Nakamura, Satoshi Gondaira, Michihito Sasaki, Masaru Usui, Hidetoshi Higuchi, Hirofumi Sawa, Yutaka Tamura, Hidetomo Iwano. Complete Genome Sequence of a Veterinary Pseudomonas aeruginosa Isolate, Pa12. Microbiology Resource Announcements. 2021; 10 (26):e0039821.

Chicago/Turabian Style

Keisuke Nakamura; Jumpei Fujiki; Takaaki Furusawa; Tomohiro Nakamura; Satoshi Gondaira; Michihito Sasaki; Masaru Usui; Hidetoshi Higuchi; Hirofumi Sawa; Yutaka Tamura; Hidetomo Iwano. 2021. "Complete Genome Sequence of a Veterinary Pseudomonas aeruginosa Isolate, Pa12." Microbiology Resource Announcements 10, no. 26: e0039821.

Journal article
Published: 11 June 2021 in Pathogens
Reads 0
Downloads 0

Rabies remains endemic in Zambia. Despite conducting canine vaccinations in Lusaka district, the vaccination coverage and actual seropositivity in the dog population in Lusaka district are rarely evaluated. This study estimated the seropositivity-based immunization coverage in the owned dog population in Lusaka district using the expanded program on immunization cluster survey method. The time-series trend of neutralizing antibodies against rabies in vaccinated dogs was also evaluated. Of 366 dogs in 200 dog-owning households in Lusaka district, blood samples were collected successfully from 251 dogs. In the sampled dogs, 42.2% (106/251) had an antibody titer ≥0.5 IU/mL. When the 115 dogs whose blood was not collected were assumed to be seronegative, the minimum immunization coverage in Lusaka district’s owned dog population was estimated at 29.0% (95% confidence interval: 22.4–35.5). It was also found that a single vaccination with certified vaccines is capable of inducing protective levels of antibodies. In contrast, higher antibody titers were observed in multiple-vaccinated dogs than in single-vaccinated dogs, coupled with the observation of a decline in antibody titer over time. These results suggest the importance of continuous booster immunization to maintain herd immunity and provide useful information to plan mass vaccination against rabies in Zambia.

ACS Style

Chiho Kaneko; Michihito Sasaki; Ryosuke Omori; Ryo Nakao; Chikako Kataoka-Nakamura; Ladslav Moonga; Joseph Ndebe; Walter Muleya; Edgar Simulundu; Bernard Hang’Ombe; George Dautu; Masahiro Kajihara; Akina Mori-Kajihara; Yongjin Qiu; Naoto Ito; Herman Chambaro; Chihiro Sugimoto; Hideaki Higashi; Ayato Takada; Hirofumi Sawa; Aaron Mweene; Norikazu Isoda. Immunization Coverage and Antibody Retention against Rabies in Domestic Dogs in Lusaka District, Zambia. Pathogens 2021, 10, 738 .

AMA Style

Chiho Kaneko, Michihito Sasaki, Ryosuke Omori, Ryo Nakao, Chikako Kataoka-Nakamura, Ladslav Moonga, Joseph Ndebe, Walter Muleya, Edgar Simulundu, Bernard Hang’Ombe, George Dautu, Masahiro Kajihara, Akina Mori-Kajihara, Yongjin Qiu, Naoto Ito, Herman Chambaro, Chihiro Sugimoto, Hideaki Higashi, Ayato Takada, Hirofumi Sawa, Aaron Mweene, Norikazu Isoda. Immunization Coverage and Antibody Retention against Rabies in Domestic Dogs in Lusaka District, Zambia. Pathogens. 2021; 10 (6):738.

Chicago/Turabian Style

Chiho Kaneko; Michihito Sasaki; Ryosuke Omori; Ryo Nakao; Chikako Kataoka-Nakamura; Ladslav Moonga; Joseph Ndebe; Walter Muleya; Edgar Simulundu; Bernard Hang’Ombe; George Dautu; Masahiro Kajihara; Akina Mori-Kajihara; Yongjin Qiu; Naoto Ito; Herman Chambaro; Chihiro Sugimoto; Hideaki Higashi; Ayato Takada; Hirofumi Sawa; Aaron Mweene; Norikazu Isoda. 2021. "Immunization Coverage and Antibody Retention against Rabies in Domestic Dogs in Lusaka District, Zambia." Pathogens 10, no. 6: 738.

Letter
Published: 11 May 2021 in Nature Immunology
Reads 0
Downloads 0

Efficient immune responses against viral infection are determined by sufficient activation of nucleic acid sensor–mediated innate immunity1,2. Coronavirus disease 2019, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), remains an ongoing global pandemic. It is an urgent challenge to clarify the innate recognition mechanism to control this virus. Here we show that retinoic acid–inducible gene-I (RIG-I) sufficiently restrains SARS-CoV-2 replication in human lung cells in a type I/III interferon (IFN)-independent manner. RIG-I recognizes the 3′ untranslated region of the SARS-CoV-2 RNA genome via the helicase domains, but not the C-terminal domain. This new mode of RIG-I recognition does not stimulate its ATPase, thereby aborting the activation of the conventional mitochondrial antiviral-signaling protein-dependent pathways, which is in accordance with lack of cytokine induction. Nevertheless, the interaction of RIG-I with the viral genome directly abrogates viral RNA-dependent RNA polymerase mediation of the first step of replication. Consistently, genetic ablation of RIG-I allows lung cells to produce viral particles that expressed the viral spike protein. By contrast, the anti-SARS-CoV-2 activity was restored by all-trans retinoic acid treatment through upregulation of RIG-I protein expression in primary lung cells derived from patients with chronic obstructive pulmonary disease. Thus, our findings demonstrate the distinctive role of RIG-I as a restraining factor in the early phase of SARS-CoV-2 infection in human lung cells. RIG-I is a cytosolic nucleic acid sensor triggering type I IFN production. Takaoka and colleagues find that RIG-I recognizes SARS-CoV-2 RNA in a noncanonical manner and fails to activate type I IFN, but it directly restricts viral replication.

ACS Style

Taisho Yamada; Seiichi Sato; Yuki Sotoyama; Yasuko Orba; Hirofumi Sawa; Hajime Yamauchi; Michihito Sasaki; Akinori Takaoka. RIG-I triggers a signaling-abortive anti-SARS-CoV-2 defense in human lung cells. Nature Immunology 2021, 22, 820 -828.

AMA Style

Taisho Yamada, Seiichi Sato, Yuki Sotoyama, Yasuko Orba, Hirofumi Sawa, Hajime Yamauchi, Michihito Sasaki, Akinori Takaoka. RIG-I triggers a signaling-abortive anti-SARS-CoV-2 defense in human lung cells. Nature Immunology. 2021; 22 (7):820-828.

Chicago/Turabian Style

Taisho Yamada; Seiichi Sato; Yuki Sotoyama; Yasuko Orba; Hirofumi Sawa; Hajime Yamauchi; Michihito Sasaki; Akinori Takaoka. 2021. "RIG-I triggers a signaling-abortive anti-SARS-CoV-2 defense in human lung cells." Nature Immunology 22, no. 7: 820-828.

Article
Published: 10 May 2021 in Journal of Virology
Reads 0
Downloads 0

Proteolytic cleavage of the viral VP4 protein is essential for virion maturation and infectivity in group A rotaviruses (RVAs). In cell culture, RVAs are propagated in culture medium supplemented with the exogenous protease trypsin, which cleaves VP4 and induces the maturation of progeny RVA virions.

ACS Style

Michihito Sasaki; Yukari Itakura; Mai Kishimoto; Koshiro Tabata; Kentaro Uemura; Naoto Ito; Makoto Sugiyama; Christida E. Wastika; Yasuko Orba; Hirofumi Sawa. Host Serine Proteases TMPRSS2 and TMPRSS11D Mediate Proteolytic Activation and Trypsin-Independent Infection in Group A Rotaviruses. Journal of Virology 2021, 95, 1 .

AMA Style

Michihito Sasaki, Yukari Itakura, Mai Kishimoto, Koshiro Tabata, Kentaro Uemura, Naoto Ito, Makoto Sugiyama, Christida E. Wastika, Yasuko Orba, Hirofumi Sawa. Host Serine Proteases TMPRSS2 and TMPRSS11D Mediate Proteolytic Activation and Trypsin-Independent Infection in Group A Rotaviruses. Journal of Virology. 2021; 95 (11):1.

Chicago/Turabian Style

Michihito Sasaki; Yukari Itakura; Mai Kishimoto; Koshiro Tabata; Kentaro Uemura; Naoto Ito; Makoto Sugiyama; Christida E. Wastika; Yasuko Orba; Hirofumi Sawa. 2021. "Host Serine Proteases TMPRSS2 and TMPRSS11D Mediate Proteolytic Activation and Trypsin-Independent Infection in Group A Rotaviruses." Journal of Virology 95, no. 11: 1.

Preprint content
Published: 30 April 2021
Reads 0
Downloads 0

Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) possesses a discriminative polybasic cleavage motif in its spike protein that is recognized by host furin protease. Proteolytic cleavage activates the spike protein and influences both the cellular entry pathway and cell tropism of SARS-CoV-2. Here, we investigated the impact of the furin cleavage site on viral growth and pathogensis using a hamster animal model infected with SARS-CoV-2 variants bearing mutations at the furin cleavage site (S gene mutants). In the airway tissues of hamsters, the S gene mutants exhibited a low growth property. In contrast to parental pathogenic SARS-CoV-2, hamsters infected with the S gene mutants showed no body weight loss and only a mild inflammatory response, indicating the attenuated variant nature of S gene mutants. We reproduced the attenuated growth of S gene mutants in primary differenciated human airway epithelial cells. This transient infection was enough to induce protective neutralizing antibodies crossreacting with different SARS-CoV-2 lineages. Consequently, hamsters inoculated with S gene mutants showed resistance to subsequent infection with both the parental strain and the currently emerging SARS-CoV-2 variants belonging to lineages B.1.1.7 and P.1. Together, our findings revealed that the loss of the furin cleavage site causes attenuation in the airway tissues of SARS-CoV-2 and highlights the potential benefits of S gene mutants as potential immunogens.

ACS Style

Michihito Sasaki; Shinsuke Toba; Yukari Itakura; Herman M. Chambaro; Mai Kishimoto; Koshiro Tabata; Kittiya Intaruck; Kentaro Uemura; Takao Sanaki; Akihiko Sato; William W. Hall; Yasuko Orba; Hirofumi Sawa. SARS-CoV-2 bearing a mutation at the S1/S2 cleavage site exhibits attenuated virulence and confers protective immunity. 2021, 1 .

AMA Style

Michihito Sasaki, Shinsuke Toba, Yukari Itakura, Herman M. Chambaro, Mai Kishimoto, Koshiro Tabata, Kittiya Intaruck, Kentaro Uemura, Takao Sanaki, Akihiko Sato, William W. Hall, Yasuko Orba, Hirofumi Sawa. SARS-CoV-2 bearing a mutation at the S1/S2 cleavage site exhibits attenuated virulence and confers protective immunity. . 2021; ():1.

Chicago/Turabian Style

Michihito Sasaki; Shinsuke Toba; Yukari Itakura; Herman M. Chambaro; Mai Kishimoto; Koshiro Tabata; Kittiya Intaruck; Kentaro Uemura; Takao Sanaki; Akihiko Sato; William W. Hall; Yasuko Orba; Hirofumi Sawa. 2021. "SARS-CoV-2 bearing a mutation at the S1/S2 cleavage site exhibits attenuated virulence and confers protective immunity." , no. : 1.

Journal article
Published: 28 April 2021
Reads 0
Downloads 0

An estimated 75% or more of the human rabies cases in Africa occur in rural settings, which underscores the importance of rabies control in these areas. Understanding dog demographics can help design strategies for rabies control and plan and conduct canine mass vaccination campaigns effectively in African countries. A cross-sectional survey was conducted to investigate domestic dog demographics in Kalambabakali, in the rural Mazabuka District of Zambia. The population of ownerless dogs and the total achievable vaccination coverage among the total dog population was estimated using the capture-recapture-based Bayesian model by conducting a canine mass vaccination campaign. This study revealed that 29% of the domestic dog population was under one year old, and 57.7% of those were under three months old and thus were not eligible for the canine rabies vaccination in Zambia. The population growth was estimated at 15% per annum based on the cross-sectional household survey. The population of ownerless dogs was estimated to be small, with an ownerless-to-owned-dog ratio of 0.01–0.06 in the target zones. The achieved overall vaccination coverage from the first mass vaccination was estimated 19.8–51.6%. This low coverage was principally attributed to the owners’ lack of information, unavailability, and dog-handling difficulties. The follow-up mass vaccination campaign achieved an overall coverage of 54.8–76.2%. This paper indicates the potential for controlling canine rabies through mass vaccination in rural Zambia. Rabies education and responsible dog ownership are required to achieve high and sustainable vaccination coverage. Our findings also propose including puppies below three months old in the target population for rabies vaccination and emphasize that securing an annual enforcement of canine mass vaccination that reaches 70% coverage in the dog population is necessary to maintain protective herd immunity.

ACS Style

Chiho Kaneko; Ryosuke Omori; Michihito Sasaki; Chikako Kataoka-Nakamura; Edgar Simulundu; Walter Muleya; Ladslav Moonga; Joseph Ndebe; Bernard M. Hang’Ombe; George Dautu; Yongjin Qiu; Ryo Nakao; Masahiro Kajihara; Akina Mori-Kajihara; Herman M. Chambaro; Hideaki Higashi; Chihiro Sugimoto; Hirofumi Sawa; Aaron S. Mweene; Ayato Takada; Norikazu Isoda. Domestic dog demographics and estimates of canine vaccination coverage in a rural area of Zambia for the elimination of rabies. 2021, 15, e0009222 .

AMA Style

Chiho Kaneko, Ryosuke Omori, Michihito Sasaki, Chikako Kataoka-Nakamura, Edgar Simulundu, Walter Muleya, Ladslav Moonga, Joseph Ndebe, Bernard M. Hang’Ombe, George Dautu, Yongjin Qiu, Ryo Nakao, Masahiro Kajihara, Akina Mori-Kajihara, Herman M. Chambaro, Hideaki Higashi, Chihiro Sugimoto, Hirofumi Sawa, Aaron S. Mweene, Ayato Takada, Norikazu Isoda. Domestic dog demographics and estimates of canine vaccination coverage in a rural area of Zambia for the elimination of rabies. . 2021; 15 (4):e0009222.

Chicago/Turabian Style

Chiho Kaneko; Ryosuke Omori; Michihito Sasaki; Chikako Kataoka-Nakamura; Edgar Simulundu; Walter Muleya; Ladslav Moonga; Joseph Ndebe; Bernard M. Hang’Ombe; George Dautu; Yongjin Qiu; Ryo Nakao; Masahiro Kajihara; Akina Mori-Kajihara; Herman M. Chambaro; Hideaki Higashi; Chihiro Sugimoto; Hirofumi Sawa; Aaron S. Mweene; Ayato Takada; Norikazu Isoda. 2021. "Domestic dog demographics and estimates of canine vaccination coverage in a rural area of Zambia for the elimination of rabies." 15, no. 4: e0009222.

Research article
Published: 28 April 2021 in PLOS Neglected Tropical Diseases
Reads 0
Downloads 0

Background An estimated 75% or more of the human rabies cases in Africa occur in rural settings, which underscores the importance of rabies control in these areas. Understanding dog demographics can help design strategies for rabies control and plan and conduct canine mass vaccination campaigns effectively in African countries. Methodology/Principal findings A cross-sectional survey was conducted to investigate domestic dog demographics in Kalambabakali, in the rural Mazabuka District of Zambia. The population of ownerless dogs and the total achievable vaccination coverage among the total dog population was estimated using the capture-recapture-based Bayesian model by conducting a canine mass vaccination campaign. This study revealed that 29% of the domestic dog population was under one year old, and 57.7% of those were under three months old and thus were not eligible for the canine rabies vaccination in Zambia. The population growth was estimated at 15% per annum based on the cross-sectional household survey. The population of ownerless dogs was estimated to be small, with an ownerless-to-owned-dog ratio of 0.01–0.06 in the target zones. The achieved overall vaccination coverage from the first mass vaccination was estimated 19.8–51.6%. This low coverage was principally attributed to the owners’ lack of information, unavailability, and dog-handling difficulties. The follow-up mass vaccination campaign achieved an overall coverage of 54.8–76.2%. Conclusions/Significance This paper indicates the potential for controlling canine rabies through mass vaccination in rural Zambia. Rabies education and responsible dog ownership are required to achieve high and sustainable vaccination coverage. Our findings also propose including puppies below three months old in the target population for rabies vaccination and emphasize that securing an annual enforcement of canine mass vaccination that reaches 70% coverage in the dog population is necessary to maintain protective herd immunity.

ACS Style

Chiho Kaneko; Ryosuke Omori; Michihito Sasaki; Chikako Kataoka-Nakamura; Edgar Simulundu; Walter Muleya; Ladslav Moonga; Joseph Ndebe; Bernard M. Hang’Ombe; George Dautu; Yongjin Qiu; Ryo Nakao; Masahiro Kajihara; Akina Mori-Kajihara; Herman M. Chambaro; Hideaki Higashi; Chihiro Sugimoto; Hirofumi Sawa; Aaron S. Mweene; Ayato Takada; Norikazu Isoda. Domestic dog demographics and estimates of canine vaccination coverage in a rural area of Zambia for the elimination of rabies. PLOS Neglected Tropical Diseases 2021, 15, e0009222 .

AMA Style

Chiho Kaneko, Ryosuke Omori, Michihito Sasaki, Chikako Kataoka-Nakamura, Edgar Simulundu, Walter Muleya, Ladslav Moonga, Joseph Ndebe, Bernard M. Hang’Ombe, George Dautu, Yongjin Qiu, Ryo Nakao, Masahiro Kajihara, Akina Mori-Kajihara, Herman M. Chambaro, Hideaki Higashi, Chihiro Sugimoto, Hirofumi Sawa, Aaron S. Mweene, Ayato Takada, Norikazu Isoda. Domestic dog demographics and estimates of canine vaccination coverage in a rural area of Zambia for the elimination of rabies. PLOS Neglected Tropical Diseases. 2021; 15 (4):e0009222.

Chicago/Turabian Style

Chiho Kaneko; Ryosuke Omori; Michihito Sasaki; Chikako Kataoka-Nakamura; Edgar Simulundu; Walter Muleya; Ladslav Moonga; Joseph Ndebe; Bernard M. Hang’Ombe; George Dautu; Yongjin Qiu; Ryo Nakao; Masahiro Kajihara; Akina Mori-Kajihara; Herman M. Chambaro; Hideaki Higashi; Chihiro Sugimoto; Hirofumi Sawa; Aaron S. Mweene; Ayato Takada; Norikazu Isoda. 2021. "Domestic dog demographics and estimates of canine vaccination coverage in a rural area of Zambia for the elimination of rabies." PLOS Neglected Tropical Diseases 15, no. 4: e0009222.

Preprint content
Published: 12 April 2021
Reads 0
Downloads 0

The COVID-19 pandemic caused by the novel coronavirus, SARS-CoV-2, has a global impact on public health. Since glycosylation of the viral envelope glycoproteins is known to be deeply associated with their immunogenicity, intensive studies on the glycans of its major glycoprotein, S protein, have been conducted. Nevertheless, the detailed site-specific glycan compositions of virion-associated S protein have not yet been clarified. Here, we conducted intensive glycoproteomic analyses of SARS-CoV-2 S protein using a combinatorial approach with two different technologies: mass spectrometry (MS) and lectin microarray. Using our unique MS1-based glycoproteomic technique, Glyco-RIDGE, in addition to MS2-based Byonic search, we identified 1,759 site-specific glycan compositions. The most frequent was HexNAc:Hex:Fuc:NeuAc:NeuGc = 6:6:1:0:0, suggesting a tri-antennary N-glycan terminating with LacNAc and having bisecting GlcNAc and a core fucose, which was found in 20 of 22 glycosylated sites. The subsequent lectin microarray analysis emphasized intensive outer arm fucosylation of glycans, which efficiently complemented the glycoproteomic features. The present results illustrate the high-resolution glycoproteomic features of SARS-CoV-2 S protein and significantly contribute to vaccine design, as well as the understanding of viral protein synthesis.

ACS Style

Takahiro Hiono; Azusa Tomioka; Hiroyuki Kaji; Michihito Sasaki; Yasuko Orba; Hirofumi Sawa; Atsushi Kuno. Combinatorial approach with mass spectrometry and lectin microarray dissected glycoproteomic features of virion-derived spike protein of SARS-CoV-2. 2021, 1 .

AMA Style

Takahiro Hiono, Azusa Tomioka, Hiroyuki Kaji, Michihito Sasaki, Yasuko Orba, Hirofumi Sawa, Atsushi Kuno. Combinatorial approach with mass spectrometry and lectin microarray dissected glycoproteomic features of virion-derived spike protein of SARS-CoV-2. . 2021; ():1.

Chicago/Turabian Style

Takahiro Hiono; Azusa Tomioka; Hiroyuki Kaji; Michihito Sasaki; Yasuko Orba; Hirofumi Sawa; Atsushi Kuno. 2021. "Combinatorial approach with mass spectrometry and lectin microarray dissected glycoproteomic features of virion-derived spike protein of SARS-CoV-2." , no. : 1.

Communication
Published: 28 February 2021 in Viruses
Reads 0
Downloads 0

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) utilizes host proteases, including a plasma membrane-associated transmembrane protease, serine 2 (TMPRSS2) to cleave and activate the virus spike protein to facilitate cellular entry. Although TMPRSS2 is a well-characterized type II transmembrane serine protease (TTSP), the role of other TTSPs on the replication of SARS-CoV-2 remains to be elucidated. Here, we have screened 12 TTSPs using human angiotensin-converting enzyme 2-expressing HEK293T (293T-ACE2) cells and Vero E6 cells and demonstrated that exogenous expression of TMPRSS11D and TMPRSS13 enhanced cellular uptake and subsequent replication of SARS-CoV-2. In addition, SARS-CoV-1 and SARS-CoV-2 share the same TTSPs in the viral entry process. Our study demonstrates the impact of host TTSPs on infection of SARS-CoV-2, which may have implications for cell and tissue tropism, for pathogenicity, and potentially for vaccine development.

ACS Style

Mai Kishimoto; Kentaro Uemura; Takao Sanaki; Akihiko Sato; William Hall; Hiroaki Kariwa; Yasuko Orba; Hirofumi Sawa; Michihito Sasaki. TMPRSS11D and TMPRSS13 Activate the SARS-CoV-2 Spike Protein. Viruses 2021, 13, 384 .

AMA Style

Mai Kishimoto, Kentaro Uemura, Takao Sanaki, Akihiko Sato, William Hall, Hiroaki Kariwa, Yasuko Orba, Hirofumi Sawa, Michihito Sasaki. TMPRSS11D and TMPRSS13 Activate the SARS-CoV-2 Spike Protein. Viruses. 2021; 13 (3):384.

Chicago/Turabian Style

Mai Kishimoto; Kentaro Uemura; Takao Sanaki; Akihiko Sato; William Hall; Hiroaki Kariwa; Yasuko Orba; Hirofumi Sawa; Michihito Sasaki. 2021. "TMPRSS11D and TMPRSS13 Activate the SARS-CoV-2 Spike Protein." Viruses 13, no. 3: 384.

Journal article
Published: 03 February 2021 in Journal of General Virology
Reads 0
Downloads 0

Encephalomyocarditis virus (EMCV) infects a wide range of hosts and can cause encephalitis, myocarditis, reproductive disorders and diabetes mellitus in selected mammalian species. As for humans, EMCV infection seems to occur by the contact with animals and can cause febrile illnesses in some infected patients. Here we isolated EMCV strain ZM12/14 from a natal multimammate mouse (Mastomys natalensis: M. natalensis) in Zambia. Pairwise sequence similarity of the ZM12/14 P1 region consisting of antigenic capsid proteins showed the highest similarity of nucleotide (80.7 %) and amino acid (96.2%) sequence with EMCV serotype 1 (EMCV-1). Phylogenetic analysis revealed that ZM12/14 clustered into EMCV-1 at the P1 and P3 regions but segregated from known EMCV strains at the P2 region, suggesting a unique evolutionary history. Reverse transcription PCR (RT-PCR) screening and neutralizing antibody assays for EMCV were performed using collected tissues and serum from various rodents (n=179) captured in different areas in Zambia. We detected the EMCV genome in 19 M. natalensis (19/179=10.6 %) and neutralizing antibody for EMCV in 33 M. natalensis (33/179=18.4 %). However, we did not detect either the genome or neutralizing antibody in other rodent species. High neutralizing antibody litres (≧320) were observed in both RT-PCR-negative and -positive animals. Inoculation of ZM12/14 caused asymptomatic persistent infection in BALB/c mice with high antibody titres and high viral loads in some organs, consistent with the above epidemiological results. This study is the first report of the isolation of EMCV in Zambia, suggesting that M. natalensis may play a role as a natural reservoir of infection.

ACS Style

Mai Kishimoto; Bernard M. Hang’Ombe; William W. Hall; Yasuko Orba; Hirofumi Sawa; Michihito Sasaki. Mastomys natalensis is a possible natural rodent reservoir for encephalomyocarditis virus. Journal of General Virology 2021, 001564 .

AMA Style

Mai Kishimoto, Bernard M. Hang’Ombe, William W. Hall, Yasuko Orba, Hirofumi Sawa, Michihito Sasaki. Mastomys natalensis is a possible natural rodent reservoir for encephalomyocarditis virus. Journal of General Virology. 2021; ():001564.

Chicago/Turabian Style

Mai Kishimoto; Bernard M. Hang’Ombe; William W. Hall; Yasuko Orba; Hirofumi Sawa; Michihito Sasaki. 2021. "Mastomys natalensis is a possible natural rodent reservoir for encephalomyocarditis virus." Journal of General Virology , no. : 001564.

Research article
Published: 21 January 2021 in PLOS Pathogens
Reads 0
Downloads 0

The spike (S) protein of Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) binds to a host cell receptor which facilitates viral entry. A polybasic motif detected at the cleavage site of the S protein has been shown to broaden the cell tropism and transmissibility of the virus. Here we examine the properties of SARS-CoV-2 variants with mutations at the S protein cleavage site that undergo inefficient proteolytic cleavage. Virus variants with S gene mutations generated smaller plaques and exhibited a more limited range of cell tropism compared to the wild-type strain. These alterations were shown to result from their inability to utilize the entry pathway involving direct fusion mediated by the host type II transmembrane serine protease, TMPRSS2. Notably, viruses with S gene mutations emerged rapidly and became the dominant SARS-CoV-2 variants in TMPRSS2-deficient cells including Vero cells. Our study demonstrated that the S protein polybasic cleavage motif is a critical factor underlying SARS-CoV-2 entry and cell tropism. As such, researchers should be alert to the possibility of de novo S gene mutations emerging in tissue-culture propagated virus strains.

ACS Style

Michihito Sasaki; Kentaro Uemura; Akihiko Sato; Shinsuke Toba; Takao Sanaki; Katsumi Maenaka; William W. Hall; Yasuko Orba; Hirofumi Sawa. SARS-CoV-2 variants with mutations at the S1/S2 cleavage site are generated in vitro during propagation in TMPRSS2-deficient cells. PLOS Pathogens 2021, 17, e1009233 .

AMA Style

Michihito Sasaki, Kentaro Uemura, Akihiko Sato, Shinsuke Toba, Takao Sanaki, Katsumi Maenaka, William W. Hall, Yasuko Orba, Hirofumi Sawa. SARS-CoV-2 variants with mutations at the S1/S2 cleavage site are generated in vitro during propagation in TMPRSS2-deficient cells. PLOS Pathogens. 2021; 17 (1):e1009233.

Chicago/Turabian Style

Michihito Sasaki; Kentaro Uemura; Akihiko Sato; Shinsuke Toba; Takao Sanaki; Katsumi Maenaka; William W. Hall; Yasuko Orba; Hirofumi Sawa. 2021. "SARS-CoV-2 variants with mutations at the S1/S2 cleavage site are generated in vitro during propagation in TMPRSS2-deficient cells." PLOS Pathogens 17, no. 1: e1009233.

Journal article
Published: 08 January 2021 in Journal of General Virology
Reads 0
Downloads 0

The genus Flavivirus includes a range of mosquito-specific viruses in addition to well-known medically important arboviruses. Isolation and comprehensive genomic analyses of viruses in mosquitoes collected in Bolivia resulted in the identification of three novel flavivirus species. Psorophora flavivirus (PSFV) was isolated from Psorophora albigenu. The coding sequence of the PSFV polyprotein shares 60 % identity with that of the Aedes-associated lineage II insect-specific flavivirus (ISF), Marisma virus. Isolated PSFV replicates in both Aedes albopictus- and Aedes aegypti-derived cells, but not in mammalian Vero or BHK-21 cell lines. Two other flaviviruses, Ochlerotatus scapularis flavivirus (OSFV) and Mansonia flavivirus (MAFV), which were identified from Ochlerotatus scapularis and Mansonia titillans, respectively, group with the classical lineage I ISFs. The protein coding sequences of these viruses share only 60 and 40 % identity with the most closely related of known lineage I ISFs, including Xishuangbanna aedes flavivirus and Sabethes flavivirus, respectively. Phylogenetic analysis suggests that MAFV is clearly distinct from the groups of the current known Culicinae-associated lineage I ISFs. Interestingly, the predicted amino acid sequence of the MAFV capsid protein is approximately two times longer than that of any of the other known flaviviruses. Our results indicate that flaviviruses with distinct features can be found at the edge of the Bolivian Amazon basin at sites that are also home to dense populations of human-biting mosquitoes.

ACS Style

Yasuko Orba; Keita Matsuno; Ryo Nakao; Kirill Kryukov; Yumi Saito; Fumihiko Kawamori; Ariel Loza Vega; Tokiko Watanabe; Tadashi Maemura; Michihito Sasaki; William W. Hall; Roy A. Hall; Juan Antonio Pereira; So Nakagawa; Hirofumi Sawa. Diverse mosquito-specific flaviviruses in the Bolivian Amazon basin. Journal of General Virology 2021, 001518 .

AMA Style

Yasuko Orba, Keita Matsuno, Ryo Nakao, Kirill Kryukov, Yumi Saito, Fumihiko Kawamori, Ariel Loza Vega, Tokiko Watanabe, Tadashi Maemura, Michihito Sasaki, William W. Hall, Roy A. Hall, Juan Antonio Pereira, So Nakagawa, Hirofumi Sawa. Diverse mosquito-specific flaviviruses in the Bolivian Amazon basin. Journal of General Virology. 2021; ():001518.

Chicago/Turabian Style

Yasuko Orba; Keita Matsuno; Ryo Nakao; Kirill Kryukov; Yumi Saito; Fumihiko Kawamori; Ariel Loza Vega; Tokiko Watanabe; Tadashi Maemura; Michihito Sasaki; William W. Hall; Roy A. Hall; Juan Antonio Pereira; So Nakagawa; Hirofumi Sawa. 2021. "Diverse mosquito-specific flaviviruses in the Bolivian Amazon basin." Journal of General Virology , no. : 001518.

Journal article
Published: 12 November 2020 in Microbiology Resource Announcements
Reads 0
Downloads 0

We report the complete genome sequence of Escherichia coli strain HUE1, isolated from the urinary catheter of a female patient, showing fluoroquinolone resistance without quinolone resistance-determining region mutations. To facilitate the exploration of the molecular characteristics of HUE1, the whole genome was sequenced using long- and short-read platforms.

ACS Style

Montgomery Munby; Jumpei Fujiki; Kotaro Aoki; Chika Kawaguchi; Keisuke Nakamura; Tomohiro Nakamura; Michihito Sasaki; Toyotaka Sato; Masaru Usui; Hirofumi Sawa; Shin-Ichi Yokota; Yutaka Tamura; Hidetomo Iwano. Whole-Genome Sequence of Fluoroquinolone-Resistant Escherichia coli HUE1, Isolated in Hokkaido, Japan. Microbiology Resource Announcements 2020, 9, 1 .

AMA Style

Montgomery Munby, Jumpei Fujiki, Kotaro Aoki, Chika Kawaguchi, Keisuke Nakamura, Tomohiro Nakamura, Michihito Sasaki, Toyotaka Sato, Masaru Usui, Hirofumi Sawa, Shin-Ichi Yokota, Yutaka Tamura, Hidetomo Iwano. Whole-Genome Sequence of Fluoroquinolone-Resistant Escherichia coli HUE1, Isolated in Hokkaido, Japan. Microbiology Resource Announcements. 2020; 9 (46):1.

Chicago/Turabian Style

Montgomery Munby; Jumpei Fujiki; Kotaro Aoki; Chika Kawaguchi; Keisuke Nakamura; Tomohiro Nakamura; Michihito Sasaki; Toyotaka Sato; Masaru Usui; Hirofumi Sawa; Shin-Ichi Yokota; Yutaka Tamura; Hidetomo Iwano. 2020. "Whole-Genome Sequence of Fluoroquinolone-Resistant Escherichia coli HUE1, Isolated in Hokkaido, Japan." Microbiology Resource Announcements 9, no. 46: 1.

Journal article
Published: 12 October 2020 in International Journal of Molecular Sciences
Reads 0
Downloads 0

Efforts to determine the mosquito genes that affect dengue virus replication have identified a number of candidates that positively or negatively modify amplification in the invertebrate host. We used deep sequencing to compare the differential transcript abundances in Aedes aegypti 14 days post dengue infection to those of uninfected Ae. aegypti. The gene lethal(2)-essential-for-life [l(2)efl], which encodes a member of the heat shock 20 protein (HSP20) family, was upregulated following dengue virus type 2 (DENV-2) infection in vivo. The transcripts of this gene did not exhibit differential accumulation in mosquitoes exposed to insecticides or pollutants. The induction and overexpression of l(2)efl gene products using poly(I:C) resulted in decreased DENV-2 replication in the cell line. In contrast, the RNAi-mediated suppression of l(2)efl gene products resulted in enhanced DENV-2 replication, but this enhancement occurred only if multiple l(2)efl genes were suppressed. l(2)efl homologs induce the phosphorylation of eukaryotic initiation factor 2α (eIF2α) in the fruit fly Drosophila melanogaster, and we confirmed this finding in the cell line. However, the mechanism by which l(2)efl phosphorylates eIF2α remains unclear. We conclude that l(2)efl encodes a potential anti-dengue protein in the vector mosquito.

ACS Style

Lucky R. Runtuwene; Shuichi Kawashima; Victor D. Pijoh; Josef S. B. Tuda; Kyoko Hayashida; Junya Yamagishi; Chihiro Sugimoto; Shoko Nishiyama; Michihito Sasaki; Yasuko Orba; Hirofumi Sawa; Tomohiko Takasaki; Anthony A. James; Takashi Kobayashi; Yuki Eshita. The Lethal(2)-Essential-for-Life [L(2)EFL] Gene Family Modulates Dengue Virus Infection in Aedes aegypti. International Journal of Molecular Sciences 2020, 21, 7520 .

AMA Style

Lucky R. Runtuwene, Shuichi Kawashima, Victor D. Pijoh, Josef S. B. Tuda, Kyoko Hayashida, Junya Yamagishi, Chihiro Sugimoto, Shoko Nishiyama, Michihito Sasaki, Yasuko Orba, Hirofumi Sawa, Tomohiko Takasaki, Anthony A. James, Takashi Kobayashi, Yuki Eshita. The Lethal(2)-Essential-for-Life [L(2)EFL] Gene Family Modulates Dengue Virus Infection in Aedes aegypti. International Journal of Molecular Sciences. 2020; 21 (20):7520.

Chicago/Turabian Style

Lucky R. Runtuwene; Shuichi Kawashima; Victor D. Pijoh; Josef S. B. Tuda; Kyoko Hayashida; Junya Yamagishi; Chihiro Sugimoto; Shoko Nishiyama; Michihito Sasaki; Yasuko Orba; Hirofumi Sawa; Tomohiko Takasaki; Anthony A. James; Takashi Kobayashi; Yuki Eshita. 2020. "The Lethal(2)-Essential-for-Life [L(2)EFL] Gene Family Modulates Dengue Virus Infection in Aedes aegypti." International Journal of Molecular Sciences 21, no. 20: 7520.

Journal article
Published: 01 October 2020 in Journal of General Virology
Reads 0
Downloads 0

Mammalian orthoreovirus (MRV) has been identified in humans, livestock and wild animals; this wide host range allows individual MRV to transmit into multiple species. Although several interspecies transmission and genetic reassortment events of MRVs among humans, livestock and wildlife have been reported, the genetic diversity and geographic distribution of MRVs in Africa are poorly understood. In this study, we report the first isolation and characterization of MRVs circulating in a pig population in Zambia. In our screening, MRV genomes were detected in 19.7 % (29/147) of faecal samples collected from pigs by reverse transcription PCR. Three infectious MRV strains (MRV-85, MRV-96 and MRV-117) were successfully isolated, and their complete genomes were sequenced. Recombination analyses based on the complete genome sequences of the isolated MRVs demonstrated that MRV-96 shared the S3 segment with a different MRV isolated from bats, and that the L1 and M3 segments of MRV-117 originated from bat and human MRVs, respectively. Our results suggest that the isolated MRVs emerged through genetic reassortment events with interspecies transmission. Given the lack of information regarding MRVs in Africa, further surveillance of MRVs circulating among humans, domestic animals and wildlife is required to assess potential risk for humans and animals.

ACS Style

Hayato Harima; Michihito Sasaki; Masahiro Kajihara; Gabriel Gonzalez; Edgar Simulundu; Eugene C. Bwalya; Yongjin Qiu; Kosuke Okuya; Mao Isono; Yasuko Orba; Ayato Takada; Bernard M. Hang’Ombe; Aaron S. Mweene; Hirofumi Sawa. Characterization of mammalian orthoreoviruses isolated from faeces of pigs in Zambia. Journal of General Virology 2020, 101, 1027 -1036.

AMA Style

Hayato Harima, Michihito Sasaki, Masahiro Kajihara, Gabriel Gonzalez, Edgar Simulundu, Eugene C. Bwalya, Yongjin Qiu, Kosuke Okuya, Mao Isono, Yasuko Orba, Ayato Takada, Bernard M. Hang’Ombe, Aaron S. Mweene, Hirofumi Sawa. Characterization of mammalian orthoreoviruses isolated from faeces of pigs in Zambia. Journal of General Virology. 2020; 101 (10):1027-1036.

Chicago/Turabian Style

Hayato Harima; Michihito Sasaki; Masahiro Kajihara; Gabriel Gonzalez; Edgar Simulundu; Eugene C. Bwalya; Yongjin Qiu; Kosuke Okuya; Mao Isono; Yasuko Orba; Ayato Takada; Bernard M. Hang’Ombe; Aaron S. Mweene; Hirofumi Sawa. 2020. "Characterization of mammalian orthoreoviruses isolated from faeces of pigs in Zambia." Journal of General Virology 101, no. 10: 1027-1036.

Journal article
Published: 11 September 2020 in Viruses
Reads 0
Downloads 0

To monitor the arthropod-borne virus transmission in mosquitoes, we have attempted both to detect and isolate viruses from 3304 wild-caught female mosquitoes in the Livingstone (Southern Province) and Mongu (Western Province) regions in Zambia in 2017. A pan-flavivirus RT-PCR assay was performed to identify flavivirus genomes in total RNA extracted from mosquito lysates, followed by virus isolation and full genome sequence analysis using next-generation sequencing and rapid amplification of cDNA ends. We isolated a newly identified Barkedji virus (BJV Zambia) (10,899 nt) and a novel flavivirus, tentatively termed Barkedji-like virus (BJLV) (10,885 nt) from Culex spp. mosquitoes which shared 96% and 75% nucleotide identity with BJV which has been isolated in Israel, respectively. These viruses could replicate in C6/36 cells but not in mammalian and avian cell lines. In parallel, a comparative genomics screening was conducted to study evolutionary traits of the 5′- and 3′-untranslated regions (UTRs) of isolated viruses. Bioinformatic analyses of the secondary structures in the UTRs of both viruses revealed that the 5′-UTRs exhibit canonical stem-loop structures, while the 3′-UTRs contain structural homologs to exoribonuclease-resistant RNAs (xrRNAs), SL-III, dumbbell, and terminal stem-loop (3′SL) structures. The function of predicted xrRNA structures to stop RNA degradation by Xrn1 exoribonuclease was further proved by the in vitro Xrn1 resistance assay.

ACS Style

Christida E. Wastika; Hayato Harima; Michihito Sasaki; Bernard M. Hang’Ombe; Yuki Eshita; Yongjin Qiu; William W. Hall; Michael T. Wolfinger; Hirofumi Sawa; Yasuko Orba. Discoveries of Exoribonuclease-Resistant Structures of Insect-Specific Flaviviruses Isolated in Zambia. Viruses 2020, 12, 1017 .

AMA Style

Christida E. Wastika, Hayato Harima, Michihito Sasaki, Bernard M. Hang’Ombe, Yuki Eshita, Yongjin Qiu, William W. Hall, Michael T. Wolfinger, Hirofumi Sawa, Yasuko Orba. Discoveries of Exoribonuclease-Resistant Structures of Insect-Specific Flaviviruses Isolated in Zambia. Viruses. 2020; 12 (9):1017.

Chicago/Turabian Style

Christida E. Wastika; Hayato Harima; Michihito Sasaki; Bernard M. Hang’Ombe; Yuki Eshita; Yongjin Qiu; William W. Hall; Michael T. Wolfinger; Hirofumi Sawa; Yasuko Orba. 2020. "Discoveries of Exoribonuclease-Resistant Structures of Insect-Specific Flaviviruses Isolated in Zambia." Viruses 12, no. 9: 1017.

Journal article
Published: 31 August 2020 in Viruses
Reads 0
Downloads 0

Bluetongue (BT) is an arthropod-borne viral disease of ruminants with serious trade and socio-economic implications. Although the disease has been reported in a number of countries in sub-Saharan Africa, there is currently no information on circulating serotypes and disease distribution in Zambia. Following surveillance for BT in domestic and wild ruminants in Zambia, BT virus (BTV) nucleic acid and antibodies were detected in eight of the 10 provinces of the country. About 40% (87/215) of pooled blood samples from cattle and goats were positive for BTV nucleic acid, while one hartebeest pool (1/43) was positive among wildlife samples. Sequence analysis of segment 2 revealed presence of serotypes 3, 5, 7, 12 and 15, with five nucleotypes (B, E, F, G and J) being identified. Segment 10 phylogeny showed Zambian BTV sequences clustering with Western topotype strains from South Africa, intimating likely transboundary spread of BTV in Southern Africa. Interestingly, two Zambian viruses and one isolate from Israel formed a novel clade, which we designated as Western topotype 4. The high seroprevalence (96.2%) in cattle from Lusaka and Central provinces and co-circulation of multiple serotypes showed that BT is widespread, underscoring the need for prevention and control strategies.

ACS Style

Herman M. Chambaro; Michihito Sasaki; Edgar Simulundu; Isaac Silwamba; Yona Sinkala; Gabriel Gonzalez; David Squarre; Paul Fandamu; Caesar H. Lubaba; Musso Munyeme; Alikhadio Maseko; Choopa Chimvwele; Liywalii Mataa; Lynnfield E. Mooya; Andrew N. Mukubesa; Hayato Harima; Kenny L. Samui; Hetron M. Munang’Andu; Martin Simuunza; King S. Nalubamba; Yongjin Qiu; Michael J. Carr; William W. Hall; Yuki Eshita; Hirofumi Sawa; Yasuko Orba. Co-Circulation of Multiple Serotypes of Bluetongue Virus in Zambia. Viruses 2020, 12, 963 .

AMA Style

Herman M. Chambaro, Michihito Sasaki, Edgar Simulundu, Isaac Silwamba, Yona Sinkala, Gabriel Gonzalez, David Squarre, Paul Fandamu, Caesar H. Lubaba, Musso Munyeme, Alikhadio Maseko, Choopa Chimvwele, Liywalii Mataa, Lynnfield E. Mooya, Andrew N. Mukubesa, Hayato Harima, Kenny L. Samui, Hetron M. Munang’Andu, Martin Simuunza, King S. Nalubamba, Yongjin Qiu, Michael J. Carr, William W. Hall, Yuki Eshita, Hirofumi Sawa, Yasuko Orba. Co-Circulation of Multiple Serotypes of Bluetongue Virus in Zambia. Viruses. 2020; 12 (9):963.

Chicago/Turabian Style

Herman M. Chambaro; Michihito Sasaki; Edgar Simulundu; Isaac Silwamba; Yona Sinkala; Gabriel Gonzalez; David Squarre; Paul Fandamu; Caesar H. Lubaba; Musso Munyeme; Alikhadio Maseko; Choopa Chimvwele; Liywalii Mataa; Lynnfield E. Mooya; Andrew N. Mukubesa; Hayato Harima; Kenny L. Samui; Hetron M. Munang’Andu; Martin Simuunza; King S. Nalubamba; Yongjin Qiu; Michael J. Carr; William W. Hall; Yuki Eshita; Hirofumi Sawa; Yasuko Orba. 2020. "Co-Circulation of Multiple Serotypes of Bluetongue Virus in Zambia." Viruses 12, no. 9: 963.

Preprint content
Published: 28 August 2020
Reads 0
Downloads 0

The spike (S) protein of Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) binds to a host cell receptor which facilitates viral entry. A polybasic motif detected at the cleavage site of the S protein has been shown to broaden the cell tropism and transmissibility of the virus. Here we examine the properties of SARS-CoV-2 variants with mutations at the S protein cleavage site that undergo inefficient proteolytic cleavage. Virus variants with S gene mutations generated smaller plaques and exhibited a more limited range of cell tropism compared to the wild-type strain. These alterations were shown to result from their inability to utilize the entry pathway involving direct fusion mediated by the host type II transmembrane serine protease, TMPRSS2. Notably, viruses with S gene mutations emerged rapidly and became the dominant SARS-CoV-2 variants in TMPRSS2-deficient cells including Vero cells. Our study demonstrated that the S protein polybasic cleavage motif is a critical factor underlying SARS-CoV-2 entry and cell tropism. As such, researchers should be alert to the possibility of de novo S gene mutations emerging in tissue-culture propagated virus strains.

ACS Style

Michihito Sasaki; Kentaro Uemura; Akihiko Sato; Takao Sanaki; Katsumi Maenaka; William W Hall; Yasuko Orba; Hirofumi Sawa. SARS-CoV-2 variants with mutations at the S1/S2 cleavage site are generated in vitro during propagation in TMPRSS2-deficient cells. 2020, 1 .

AMA Style

Michihito Sasaki, Kentaro Uemura, Akihiko Sato, Takao Sanaki, Katsumi Maenaka, William W Hall, Yasuko Orba, Hirofumi Sawa. SARS-CoV-2 variants with mutations at the S1/S2 cleavage site are generated in vitro during propagation in TMPRSS2-deficient cells. . 2020; ():1.

Chicago/Turabian Style

Michihito Sasaki; Kentaro Uemura; Akihiko Sato; Takao Sanaki; Katsumi Maenaka; William W Hall; Yasuko Orba; Hirofumi Sawa. 2020. "SARS-CoV-2 variants with mutations at the S1/S2 cleavage site are generated in vitro during propagation in TMPRSS2-deficient cells." , no. : 1.

Journal article
Published: 20 August 2020 in Viruses
Reads 0
Downloads 0

The rabies virus strain Komatsugawa (Koma), which was isolated from a dog in Tokyo in the 1940s before eradication of rabies in Japan in 1957, is known as the only existent Japanese field strain (street strain). Although this strain potentially provides a useful model to study rabies pathogenesis, little is known about its genetic and phenotypic properties. Notably, this strain underwent serial passages in rodents after isolation, indicating the possibility that it may have lost biological characteristics as a street strain. In this study, to evaluate the utility of the Koma strain for studying rabies pathogenesis, we examined the genetic properties and in vitro and in vivo phenotypes. Genome-wide genetic analyses showed that, consistent with previous findings from partial sequence analyses, the Koma strain is closely related to a Russian street strain within the Arctic-related phylogenetic clade. Phenotypic examinations in vitro revealed that the Koma strain and the representative street strains are less neurotropic than the laboratory strains. Examination by using a mouse model demonstrated that the Koma strain and the street strains are more neuroinvasive than the laboratory strains. These findings indicate that the Koma strain retains phenotypes similar to those of street strains, and is therefore useful for studying rabies pathogenesis.

ACS Style

Tatsuki Takahashi; Maho Inukai; Michihito Sasaki; Madlin Potratz; Supasiri Jarusombuti; Yuji Fujii; Shoko Nishiyama; Stefan Finke; Kentaro Yamada; Hiroki Sakai; Hirofumi Sawa; Akira Nishizono; Makoto Sugiyama; Naoto Ito. Genetic and Phenotypic Characterization of a Rabies Virus Strain Isolated from a Dog in Tokyo, Japan in the 1940s. Viruses 2020, 12, 914 .

AMA Style

Tatsuki Takahashi, Maho Inukai, Michihito Sasaki, Madlin Potratz, Supasiri Jarusombuti, Yuji Fujii, Shoko Nishiyama, Stefan Finke, Kentaro Yamada, Hiroki Sakai, Hirofumi Sawa, Akira Nishizono, Makoto Sugiyama, Naoto Ito. Genetic and Phenotypic Characterization of a Rabies Virus Strain Isolated from a Dog in Tokyo, Japan in the 1940s. Viruses. 2020; 12 (9):914.

Chicago/Turabian Style

Tatsuki Takahashi; Maho Inukai; Michihito Sasaki; Madlin Potratz; Supasiri Jarusombuti; Yuji Fujii; Shoko Nishiyama; Stefan Finke; Kentaro Yamada; Hiroki Sakai; Hirofumi Sawa; Akira Nishizono; Makoto Sugiyama; Naoto Ito. 2020. "Genetic and Phenotypic Characterization of a Rabies Virus Strain Isolated from a Dog in Tokyo, Japan in the 1940s." Viruses 12, no. 9: 914.