scholarly journals Heterologous Replicase from Cucumoviruses can Replicate Viral RNAs, but is Defective in Transcribing Subgenomic RNA4A or Facilitating Viral Movement

Viruses ◽  
2018 ◽  
Vol 10 (11) ◽  
pp. 590 ◽  
Author(s):  
Shuangyu Gao ◽  
Jinda Lu ◽  
Xiaodong Cheng ◽  
Zhouhang Gu ◽  
Qiansheng Liao ◽  
...  
Keyword(s):  
Early Stage ◽  
Helicase Domain ◽  
Undetectable Level ◽  
Long Distance ◽  
Systemic Movement ◽  
Tomato Aspermy Virus ◽  
C Terminus ◽  
The Family ◽  
Viral Movement ◽  
Long Distance Movement

Interspecific exchange of RNA1 or RNA2 between the cucumoviruses cucumber mosaic virus (CMV) and tomato aspermy virus (TAV) was reported to be non-viable in plants previously. Here we investigated viability of the reassortants between CMV and TAV in Nicotiana benthamiana plants by Agrobacterium-mediated viral inoculation. The reassortants were composed of CMV RNA1 and TAV RNA2 plus RNA3 replicated in the inoculated leaves, while they were defective in viral systemic movement at the early stage of infection. Interestingly, the reassortant containing TAV RNA1 and CMV RNA2 and RNA3 infected plants systemically, but produced RNA4A (the RNA2 subgenome) at an undetectable level. The defect in production of RNA4A was due to the 1a protein encoded by TAV RNA1, and partially restored by replacing the C-terminus (helicase domain) in TAV 1a with that of CMV 1a. Collectively, exchange of the replicase components between CMV and TAV was acceptable for viral replication, but was defective in either directing transcription of subgenomic RNA4A or facilitating viral long-distance movement. Our finding may shed some light on evolution of subgenomic RNA4A in the family Bromoviridae.

scholarly journals Unusual Long-Distance Movement Strategies of Potato mop-top virus RNAs in Nicotiana benthamiana

2009 ◽  
Vol 22 (4) ◽  
pp. 381-390 ◽  
Author(s):  
Lesley Torrance ◽  
Nina I. Lukhovitskaya ◽  
Mikhail V. Schepetilnikov ◽  
Graham H. Cowan ◽  
Angelika Ziegler ◽  
...  
Keyword(s):  
Capsid Proteins ◽  
Enzyme Linked Immunosorbent Assay ◽  
Leaf Extracts ◽  
Long Distance ◽  
Particle Assembly ◽  
Virus Particles ◽  
Systemic Movement ◽  
Translational Readthrough ◽  
Potato Mop Top Virus ◽  
Long Distance Movement

The Potato mop-top virus (PMTV) genome encodes replicase, movement, and capsid proteins on three different RNA species that are encapsidated within tubular rod-shaped particles. Previously, we showed that the protein produced on translational readthrough (RT) of the coat protein (CP) gene, CP-RT, is associated with one extremity of the virus particles, and that the two RNAs encoding replicase and movement proteins can move long distance in the absence of the third RNA (RNA-CP) that encodes the capsid proteins, CP and CP-RT. Here, we examined the roles of the CP and CP-RT proteins on RNA movement using infectious clones carrying mutations in the CP and CP-RT coding domains. The results showed that, in infections established with mutant RNA-CP expressing CP together with truncated CP-RT, systemic movement of the mutant RNA-CP was inhibited but not the movement of the other two RNAs. Furthermore, RNA-CP long-distance movement was inhibited in a mutant clone expressing only CP in the absence of the CP-RT polypeptide. CP-RT was not necessary for particle assembly because virions were observed in leaf extracts infected with the CP-RT deletion mutants. RNA-CP moved long distance when protein expression was suppressed completely or when CP expression was suppressed so that only CP-RT or truncated CP-RT was expressed. CP-RT but not CP interacted with the movement protein TGB1 in the yeast two-hybrid system. CP-RT and TGB1 were detected by enzyme-linked immunosorbent assay in virus particles and the long-distance movement of RNA-CP was correlated with expression of CP-RT that interacted with TGB1; mutant RNA-CP expressing truncated CP-RT proteins that did not interact with TGB1 formed virions but did not move to upper noninoculated leaves. The results indicate that PMTV RNA-CP can move long distance in two distinct forms: either as a viral ribonucleoprotein complex or as particles that are most likely associated with CP-RT and TGB1.

scholarly journals Systemic movement of a movement-deficient strain of Cucumber mosaic virus in zucchini squash is facilitated by a cucurbit-infecting potyvirus

2002 ◽  
Vol 83 (12) ◽  
pp. 3173-3178 ◽  
Author(s):  
Seung Kook Choi ◽  
Ju Yeon Yoon ◽  
Ki Hyun Ryu ◽  
Jang Kyung Choi ◽  
Peter Palukaitis ◽  
...  
Keyword(s):  
Cucumber Mosaic Virus ◽  
Mosaic Virus ◽  
Cucurbita Pepo ◽  
Zucchini Yellow Mosaic Virus ◽  
Yellow Mosaic Virus ◽  
Long Distance ◽  
Systemic Movement ◽  
Tissue Print ◽  
Long Distance Movement

Zucchini squash (Cucurbita pepo) is a systemic host for most strains of the cucumovirus Cucumber mosaic virus (CMV), although the long-distance movement of the M strain of CMV (M-CMV) is inhibited in some cultivars. However, co-infection of zucchini plants with M-CMV and the potyvirus Zucchini yellow mosaic virus strain A (ZYMV-A) allowed M-CMV to move systemically, as demonstrated by tissue-print analysis. These doubly infected plants exhibited severe synergism in pathology. Infection of zucchini squash by M-CMV and an attenuated strain of ZYMV (ZYMV-AG) showed a milder synergy in pathology, in which ZYMV-AG also facilitated the long-distance movement of M-CMV similar to that promoted by ZYMV-A. Variation in the extent of synergy in pathology by the two strains of ZYMV did not correlate with differences in levels of accumulation of either virus. Thus, the extent of synergy in pathology is at least in part independent of the resistance-neutralizing function of the potyvirus.

scholarly journals ICTV Virus Taxonomy Profile: Alphaflexiviridae

2020 ◽  
Vol 101 (7) ◽  
pp. 699-700 ◽  
Author(s):  
Jan F. Kreuze ◽  
Anna Maria Vaira ◽  
Wulf Menzel ◽  
Thierry Candresse ◽  
Sergey K. Zavriev ◽  
...  
Keyword(s):  
Triple Gene Block ◽  
International Committee ◽  
Replication Proteins ◽  
Virus Taxonomy ◽  
Long Distance ◽  
Gene Block ◽  
The Family ◽  
Single Exception ◽  
Distinct Lineage ◽  
Long Distance Movement

The family Alphaflexiviridae includes viruses with flexuous filamentous virions that are 470–800 nm in length and 12–13 nm in diameter. Alphaflexiviruses have a single-stranded, positive-sense RNA genome of 5.5–9 kb. They infect plants and plant-infecting fungi. They share a distinct lineage of alphavirus-like replication proteins that is unusual in lacking any recognized protease domain. With a single exception, cell-to-cell and long-distance movement is facilitated by triple gene block proteins in plant-infecting genera. This is a summary of the International Committee on Taxonomy of Viruses (ICTV) Report on the family Alphaflexiviridae, which is available at www.ictv.global/report/alphaflexiviridae.

scholarly journals The Capsid Protein of Turnip Crinkle Virus Overcomes Two Separate Defense Barriers To Facilitate Systemic Movement of the Virus in Arabidopsis

2010 ◽  
Vol 84 (15) ◽  
pp. 7793-7802 ◽  
Author(s):  
Mingxia Cao ◽  
Xiaohong Ye ◽  
Kristen Willie ◽  
Junyan Lin ◽  
Xiuchun Zhang ◽  
...  
Keyword(s):  
Capsid Protein ◽  
Viral Genome ◽  
Single Amino Acid ◽  
Silencing Suppressor ◽  
Turnip Crinkle Virus ◽  
Coding Region ◽  
Long Distance ◽  
Virus Particles ◽  
Systemic Movement ◽  
Long Distance Movement

ABSTRACT The capsid protein (CP) of Turnip crinkle virus (TCV) is a multifunctional protein needed for virus assembly, suppression of RNA silencing-based antiviral defense, and long-distance movement in infected plants. In this report, we have examined genetic requirements for the different functions of TCV CP and evaluated the interdependence of these functions. A series of TCV mutants containing alterations in the CP coding region were generated. These alterations range from single-amino-acid substitutions and domain truncations to knockouts of CP translation. The latter category also contained two constructs in which the CP coding region was replaced by either the cDNA of a silencing suppressor of a different virus or that of green fluorescent protein. These mutants were used to infect Arabidopsis plants with diminished antiviral silencing capability (dcl2 dcl3 dcl4 plants). There was a strong correlation between the ability of mutants to reach systemic leaves and the silencing suppressor activity of mutant CP. Virus particles were not essential for entry of the viral genome into vascular bundles in the inoculated leaves in the absence of antiviral silencing. However, virus particles were necessary for egress of the viral genome from the vasculature of systemic leaves. Our experiments demonstrate that TCV CP not only allows the viral genome to access the systemic movement channel through silencing suppression but also ensures its smooth egress by way of assembled virus particles. These results illustrate that efficient long-distance movement of TCV requires both functions afforded by the CP.

scholarly journals The C Terminus of Brome Mosaic Virus Coat Protein Controls Viral Cell-to-Cell and Long-Distance Movement

2001 ◽  
Vol 75 (11) ◽  
pp. 5385-5390 ◽  
Author(s):  
Yasushi Okinaka ◽  
Kazuyuki Mise ◽  
Eri Suzuki ◽  
Tetsuro Okuno ◽  
Iwao Furusawa
Keyword(s):  
Coat Protein ◽  
Mosaic Virus ◽  
Plant Species ◽  
Rna Virus ◽  
Brome Mosaic Virus ◽  
Long Distance ◽  
C Terminus ◽  
Specific Factors ◽  
Virus Coat ◽  
Long Distance Movement

ABSTRACT To investigate the functional domains of the coat protein (CP; 189 amino acids) of Brome mosaic virus, a plant RNA virus, 19 alanine-scanning mutants were constructed and tested for their infectivity in barley and Nicotiana benthamiana. Despite its apparent normal replicative competence and CP production, the C-terminal mutant F184A produced no virions. Furthermore, virion-forming C-terminal mutants P178A and D182A failed to move from cell to cell in both plant species, and mutants D181A and V187A showed host-specific movement. These results indicate that the C-terminal region of CP plays some important roles in virus movement and encapsidation. The specificity of certain mutations for viral movement in two different plant species is evidence for the involvement of host-specific factors.

scholarly journals Formation of virions is strictly required for turnip yellows virus long-distance movement in plants

2014 ◽  
Vol 95 (2) ◽  
pp. 496-505 ◽  
Author(s):  
Clémence Hipper ◽  
Baptiste Monsion ◽  
Diane Bortolamiol-Bécet ◽  
Véronique Ziegler-Graff ◽  
Véronique Brault
Keyword(s):  
Minor Component ◽  
Long Distance ◽  
Virus Particles ◽  
Systemic Movement ◽  
Long Distance Transport ◽  
Viral Particles ◽  
Turnip Yellows Virus ◽  
In Trans ◽  
Long Distance Movement ◽  
Distance Transport

Viral genomic RNA of the Turnip yellows virus (TuYV; genus Polerovirus; family Luteoviridae) is protected in virions formed by the major capsid protein (CP) and the minor component, the readthrough (RT*) protein. Long-distance transport, used commonly by viruses to systemically infect host plants, occurs in phloem sieve elements and two viral forms of transport have been described: virions and ribonucleoprotein (RNP) complexes. With regard to poleroviruses, virions have always been presumed to be the long-distance transport form, but the potential role of RNP complexes has not been investigated. Here, we examined the requirement of virions for polerovirus systemic movement by analysing CP-targeted mutants that were unable to form viral particles. We confirmed that TuYV mutants that cannot encapsidate into virions are not able to reach systemic leaves. To completely discard the possibility that the introduced mutations in CP simply blocked the formation or the movement of RNP complexes, we tested in trans complementation of TuYV CP mutants by providing WT CP expressed in transgenic plants. WT CP was able to facilitate systemic movement of TuYV CP mutants and this observation was always correlated with the formation of virions. This demonstrated clearly that virus particles are essential for polerovirus systemic movement.

scholarly journals The Bundle Sheath-Phloem Interface of Cucumis sativus Is a Boundary to Systemic Infection by Tomato Aspermy Virus

1998 ◽  
Vol 11 (2) ◽  
pp. 109-114 ◽  
Author(s):  
Jeremy R. Thompson ◽  
Fernando García-Arenal
Keyword(s):  
Cucumber Mosaic Virus ◽  
Mosaic Virus ◽  
Systemic Infection ◽  
Bundle Sheath ◽  
Functional Difference ◽  
Reassortant Virus ◽  
Long Distance ◽  
Mesophyll Cells ◽  
Systemic Movement ◽  
Tomato Aspermy Virus

The progress of infection of two cucumoviruses in cucumber plants was analyzed immunohistochemically. Strain Fny of cucumber mosaic virus (CMV, FFF) was found to infect cucumber tissues systemically by 6 days postinoculation (dpi), while a reassortant virus with RNAs 1+2 of Fny-CMV plus RNA3 of strain 1 of tomato aspermy virus (FFT) was unable to move long distance and infect cucumber plants systemically. FFF infection of the vasculature was detected 6 dpi in the phloem of a low percentage of both minor (order VII–VI) and major (order V–IV) veins. At 9 dpi, infection was detected in phloem cells of about 50% of both minor and major veins. FFT colonization of inoculated cotyledons followed a pathway similar to that of FFF, but virus accumulation was never detected in vascular tissues. In minor or major veins, FFT infection was arrested at the bundle sheath (BS), and at 9 dpi was not detected in intermediary or other phloem cells. Thus, our data indicate that the BS-phloem interface is a boundary for the systemic movement of these viruses in cucumber, and provide evidence of a functional difference between the plasmodesmata connecting mesophyll cells, as well as mesophyll and BS cells, which allow the movement of both FFF and FFT, from the plasmodesmata connecting BS and phloem, which allow movement of FFF but not of FFT.

scholarly journals The C terminus of the movement protein of Brome mosaic virus controls the requirement for coat protein in cell-to-cell movement and plays a role in long-distance movement

2004 ◽  
Vol 85 (6) ◽  
pp. 1751-1761 ◽  
Author(s):  
Atsushi Takeda ◽  
Masanori Kaido ◽  
Tetsuro Okuno ◽  
Kazuyuki Mise
Keyword(s):  
Coat Protein ◽  
Mosaic Virus ◽  
Movement Protein ◽  
Cell Movement ◽  
Brome Mosaic Virus ◽  
Wild Type ◽  
Long Distance ◽  
C Terminus ◽  
Mouth Disease Virus ◽  
Long Distance Movement

The 3a movement protein (MP) plays a central role in the movement of Brome mosaic virus (BMV). To identify the functional regions in BMV MP, 24 alanine-scanning (AS) MP mutants of BMV were constructed. Infectivity of the AS mutants in the host plant Chenopodium quinoa showed that the central region of BMV MP is important for viral movement and both termini of BMV MP have effects on the development of systemic symptoms. A green-fluorescent-protein-expressing RNA3-based BMV vector containing a 2A sequence from Foot-and-mouth disease virus was also constructed. Using this vector, two AS mutants that showed more efficient cell-to-cell movement than wild-type BMV were identified. The MPs of these two AS mutants, which have mutations at their C termini, mediated cell-to-cell movement independently of coat protein (CP), unlike wild-type BMV MP. Furthermore, a BMV mutant with a truncation in the C-terminal 42 amino acids of MP was also able to move from cell to cell without CP, but did not move systemically, even in the presence of CP. These results and an encapsidation analysis suggest that the C terminus of BMV MP is involved in the requirement for CP in cell-to-cell movement and plays a role in long-distance movement. Furthermore, the ability to spread locally and form virions is not sufficient for the long-distance movement of BMV. The roles of MP and CP in BMV movement are discussed.

scholarly journals Cytoplasmic and nuclear Sw-5b synergistically induce plant immune responses to inhibit different viral infection steps

2020 ◽  
Author(s):  
Hongyu Chen ◽  
Xin Qian ◽  
Xiaojiao Chen ◽  
Tongqing Yang ◽  
Mingfeng Feng ◽  
...  
Keyword(s):  
Virus Infection ◽  
Immune Responses ◽  
Viral Replication ◽  
Host Response ◽  
Host Immunity ◽  
Leucine Rich Repeat ◽  
Long Distance ◽  
Systemic Movement ◽  
Cell Death Response ◽  
Long Distance Movement

AbstractPlant intracellular nucleotide binding-leucine-rich repeat (NLR) receptors play critical roles in mediating host immunity to pathogen attack. Successful virus infection in plant involves several essential steps including viral replication, intercellular and long-distance movement. How plant NLRs induce resistances against virus infection remains largely unknown. We demonstrated here that tomato NLR Sw-5b locates to cytoplasm and nucleus, respectively, to play different roles in inducing host resistances against tospovirus infection. The cytoplasmic Sw-5b functions to induce a strong cell death response to inhibit TSWV replication. This host response is, however, insufficient to block viral intercellular and long-distance movement. The nucleus-localized Sw-5b triggers a host defense that weakly inhibit viral replication but strongly impede virus intercellular and systemic movement. Furthermore, the cytoplasmic and nuclear Sw-5b act synergistically to confer a strong immunity to TSWV infection. Our finding adds a new knowledge to our current understanding on the plant NLRs-triggered immunity against virus infection.

From sand to sea: tracing the production and trade in glass beads from the 10th-century Cirebon shipwreck in the Java Sea

2020 ◽  
Author(s):  
Carolyn Swan
Keyword(s):  
Glass Production ◽  
Glass Beads ◽  
Rock Crystal ◽  
Long Distance ◽  
Merchant Ship ◽  
The Indian Ocean ◽  
Java Sea ◽  
Indian Ocean World ◽  
Long Distance Movement ◽  
Lapis Lazuli

Around the year 970 CE, a merchant ship carrying an assortment of goods from East Africa, Persia, India, Sri Lanka, Southeast Asia, and China foundered and sank to the bottom of the Java Sea. Thousands of beads made from many different materials—ceramic, jet, coral, banded stone, lapis lazuli, rock crystal, sapphire, ruby, garnet, pearl, gold, and glass—attest to the long-distance movement and trade of these small and often precious objects throughout the Indian Ocean world. The beads made of glass are of particular interest, as closely-dated examples are very rare and there is some debate as to where glass beads were being made and traded during this period of time. This paper examines 18 glass beads from the Cirebon shipwreck that are now in the collection of Qatar Museums, using a comparative typological and chemical perspective within the context of the 10th-century glass production. Although it remains uncertain where some of the beads were made, the composition of the glass beads points to two major production origins for the glass itself: West Asia and South Asia.

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