• Applied Microscopy
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• 제52권
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• pp.11.1-11.9
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• 2022

Zoonotic poxvirus infections pose significant threat to human health as we have witnessed recent spread of monkeypox. Therefore, insights into molecular mechanism behind poxvirus replication cycle are needed for the development of efficient antiviral strategies. Virion assembly is one of the key steps that determine the fate of replicating poxviruses. However, in-depth understanding of poxvirus assembly is challenging due to the complex nature of multi-step morphogenesis and heterogeneous virion structures. Despite these challenges, decades of research have revealed virion morphologies at various maturation stages, critical protein components and interactions with host cell compartments. Transmission electron microscopy has been employed as an indispensable tool for the examination of virion morphology, and more recently for the structure determination of protein complexes. In this review, we describe some of the major findings in poxvirus morphogenesis and the contributions of continuously advancing electron microscopy techniques.

• BMB Reports
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• 제46권10호
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• pp.495-500
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• 2013

Turnip yellow mosaic virus (TYMV) is a positive strand RNA virus. We have modified TYMV coat protein (CP) by inserting a c-Myc epitope peptide at the N- or C-terminus of the CP, and have examined its effect on assembly. We introduced the recombinant CP constructs into Nicotiana benthamiana leaves by agroinfiltration. Examination of the leaf extracts by agarose gel electrophoresis and Western blot analysis showed that the CP modified at the N-terminus produced a band co-migrating with wild-type virions. With C-terminal modification, however, the detected bands moved faster than the wild-type virions. To further examine the effect, TYMV constructs producing the modified CPs were prepared. With N-terminal modification, viral RNAs were protected from RNase A. In contrast, the viral RNAs were not protected with C-terminal modification. Overall, the results suggest that virion assembly and RNA packaging occur properly when the N-terminus of CP is modified, but not when the C-terminus is modified.

• 식물병연구
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• 제11권2호
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• pp.98-105
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• 2005

기주 식물체 내에서 식물바이러스의 증식과 이동 여부는 바이러스 게놈과 기주 간의 상호작용에 의해 결정된다. 바이러스는 기주 내에서 바이러스가 증식하고 이동하기 위해서는 기주의 요소들을 이용해야 하며, 이러한 기주 요소들은 바이러스의 기주내 침입(entry),바이러스 유전자의 발현, 그리고 바이러스 입자형성(virion assembly) 등 모든 과정에서 직접적으로 관여를 하거나, 또는 기주 단백질 발현과 저항성을 조절하여 바이러스 증식에 간접적으로 관여를 한다. 기주 요소들과 상호작용을 통해서 바이러스 증식에 관여함으로써, 기주 특이성 및 바이러스의 병 발생에 관여를 할 것으로 보고 있다.

• Journal of Microbiology
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• 제34권4호
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• pp.311-315
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• 1996

The retroviral Gag polyprotein directs the assembly of virion particles and plays an important role in some events after entry into a host cell. The Gag polyprotein of a virus mixture is responsible for inducing murine acquired immunodeficiency syndrome (MAIDS) when injected into susceptible strains of mice. In order to identify the host cellular proteins which interact with the MAIDS virus Gag proteins and possibly mediate the function of the Gag proteins, mouse T-cell leukemic cDNA expression library was screened using the yeast GAL4 two hybrid system. Of 11 individual positive clones, the clone Y1 was selected for the study of protein-protein interaction. Its DNA sequence revealed that it was an exact match to the murine SH3 domain-containing protein SH3P8. It is expressed as 2.4 kbp transcripts in testis at higher levels and in various tissues tested at lower levels. Glutathione S-transferase-Y1 fusion protein binds tightly to $Pr60^{def-gag}$ as well as $Pr65^{eco-gag}$.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.125.3-126
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• 2003

A near full-length sequence of a new tobamovirus infecting Hibiscus rosa-sinensis L. was determined. The genome consists of 58 nucleotides (nt) 5' UTR, followed by a 4.9 kb ORF which methyl transferase helicase domain (128 kDa), readthrough protein RNA dependent RNA polymerase (RdRp) 185 kDa and a 52 kDa protein. The 128 kDa protein had a maximum homology of 51.4 ％ to TMGMV and amino acids (an) were 54.3 ％ identical to TMV- vulgare strain. The 185 kDa RdRp had a maximum homology of 53.5％ to TMV-Ob and KGMMV-Y and a 59.6％ homology at the an level to CGMMV-SH. The MP gene encodes 282 aa and its theoretical molecular weight is 30.4 kDa. The nt and an sequence identities of MP ranged from 38.8％ to 43.9％ and 30.9％ to 37.9％, respectively. The CP gene encodes 163 residues and with a theoretical molecular weight of 18.2 kDa The (nt) and aa sequences of the CP were 46.9 ％ to 51.6％ and 45.3％ to 57.1％ identical to other tobamoviruses, respectively. The predicted virion origin of assembly (OAS) was located in the CP gene. Phylogenetic trees generated based on the nt and as sequences of RdRp, MP and CP genes indicated that this new virus clustered with subgroup II tobamoviruses. Although the CP ORF of this virus shared a high nt and aa sequence identity with Sunn-hemp mosaic virus (SHMV), Western analysis showed that it is serologically unrelated to SHMV. We propose the name Hibiscus virus S (HVS) for this Singapore isolate. This is the first report on a near full-length sequence of a Tobamovirus that infects hibiscus.

• The Plant Pathology Journal
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• 제36권6호
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• pp.536-557
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• 2020

Sugarcane yellow leaf virus (SCYLV) is a distinct member of the Polerovirus genus of the Luteoviridae family. SCYLV is the major limitation to sugarcane production worldwide and presently occurring in most of the sugarcane growing countries. SCYLV having high genetic diversity within the species and presently ten genotypes are known to occur based on the complete genome sequence information. SCYLV is present in almost all the states of India where sugarcane is grown. Virion comprises of 180 coat protein units and are 24-29 nm in diameter. The genome of SCYLV is a monopartite and comprised of single-stranded (ss) positive-sense (+) linear RNA of about 6 kb in size. Virus genome consists of six open reading frames (ORFs) that are expressed by sub-genomic RNAs. The SCYLV is phloem-limited and transmitted by sugarcane aphid Melanaphis sacchari in a circulative and non-propagative manner. The other aphid species namely, Ceratovacuna lanigera, Rhopalosiphum rufiabdominalis, and R. maidis also been reported to transmit the virus. The virus is not transmitted mechanically, therefore, its transmission by M. sacchari has been studied in different countries. SCYLV has a limited natural host range and mainly infect sugarcane (Sachharum hybrid), grain sorghum (Sorghum bicolor), and Columbus grass (Sorghum almum). Recent insights in the protein-protein interactions of Polerovirus through protein interaction reporter (PIR) technology enable us to understand viral encoded proteins during virus replication, assembly, plant defence mechanism, short and long-distance travel of the virus. This review presents the recent understandings on virus biology, diagnosis, genetic diversity, virus-vector and host-virus interactions and conventional and next generation management approaches.