Arabidopsis RTM1 and RTM2 Genes Function in  Phloem to Restrict Long-Distance Movement of Tobacco Etch Virus

ABSTRACT Plum pox virus (PPV) is a member of the Potyvirus genus that, in nature, infects trees of the Prunus genus. Although PPV infects systemically several species of the Nicotiana genus, such as N. clevelandii and N. benthamiana, and replicates in the inoculated leaves of N. tabacum, it is unable to infect systemically the last host. The long-distance movement defect of PPV was corrected in transgenic tobacco plants expressing the 5"-terminal region of the genome of tobacco etch virus (TEV), a potyvirus that infects systemically tobacco. The fact that PPV was unable to move to upper noninoculated leaves in tobacco plants transformed with the same TEV transgene, but with a mutation in the HC protein (HC-Pro)-coding sequences, identifies the multifunctional HC-Pro as the complementing factor, and strongly suggests that a defect in an HC-Pro activity is responsible for the long-distance movement defect of PPV in tobacco. Whereas PPV HC-Pro strongly intensifies the symptoms caused by potato virus X (PVX) in the PPV systemic hosts N. clevelandii and N. benthamiana, it has no apparent effect on PVX pathogenicity in tobacco, supporting the hypothesis that long-distance movement and pathogenicity enhancement are related activities of the potyviral HC proteins. The movement defect of PPV in tobacco could also be complemented by cucumber mosaic virus in a mixed infection, demonstrating that at least some components of the long-distance machinery of the potyviruses are not strictly virus specific. A general conclusion of this work is that the HC-Pro might be a relevant factor for controlling the host range of the potyviruses.

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Cloning of the Arabidopsis RTM1 gene, which controls restriction of long-distance movement of tobacco etch virus

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.97.1.489 ◽

2000 ◽

Vol 97 (1) ◽

pp. 489-494 ◽

Cited By ~ 139

Author(s):

S. T. Chisholm ◽

S. K. Mahajan ◽

S. A. Whitham ◽

M. L. Yamamoto ◽

J. C. Carrington

Keyword(s):

Tobacco Etch Virus ◽

Long Distance ◽

Long Distance Movement

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

10.31338/uw.2083-537x.pam29.1.17 ◽

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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Faculty Opinions recommendation of Destination-selective long-distance movement of phloem proteins.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1026600.326451 ◽

2005 ◽

Author(s):

Doris Rentsch

Keyword(s):

Long Distance ◽

Long Distance Movement

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Maize resistance to Sugarcane mosaic virus

Plant Protection Science ◽

10.17221/10550-pps ◽

2017 ◽

Vol 38 (SI 2 - 6th Conf EFPP 2002) ◽

pp. 542-544

Author(s):

R. Pokorný ◽

M. Porubová

Keyword(s):

Mosaic Virus ◽

Systemic Infection ◽

Sugarcane Mosaic Virus ◽

Resistant Line ◽

Mechanisms Of Resistance ◽

Long Distance ◽

Maize Hybrids ◽

Resistant Lines ◽

Maize Resistance ◽

Long Distance Movement

Under greenhouse conditions 12 maize hybrids derived from crosses of four resistant lines with several lines of different level of susceptibility were evaluated for resistance to Czech isolate of Sugarcane mosaic virus (SCMV). These hybrids were not fully resistant to isolate of SCMV, but the symptoms on their newly growing leaves usually developed 1 to 3 weeks later in comparison with particular susceptible line, the course of infection was significantly slower and rate of infection lower. As for mechanisms of resistance, the presence of SCMV was detected by ELISA in inoculated leaves both of resistant and susceptible lines, but virus was detected 7 days later in resistant line. Systemic infection developed only in susceptible lines. These results indicate restriction of viral long distance movement in the resistant line.

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Inferring Modes of Colonization for Pest Species Using Heterozygosity Comparisons and a Shared-Allele Test

Genetics ◽

10.1093/genetics/163.2.823 ◽

2003 ◽

Vol 163 (2) ◽

pp. 823-831

Author(s):

J A Sved ◽

H Yu ◽

B Dominiak ◽

A S Gilchrist

Keyword(s):

Distance Measure ◽

Fruit Fly ◽

Small Samples ◽

Pest Species ◽

Long Distance ◽

Resampling Methods ◽

Shared Allele ◽

The Core ◽

Direct Sampling ◽

Long Distance Movement

Abstract Long-range dispersal of a species may involve either a single long-distance movement from a core population or spreading via unobserved intermediate populations. Where the new populations originate as small propagules, genetic drift may be extreme and gene frequency or assignment methods may not prove useful in determining the relation between the core population and outbreak samples. We describe computationally simple resampling methods for use in this situation to distinguish between the different modes of dispersal. First, estimates of heterozygosity can be used to test for direct sampling from the core population and to estimate the effective size of intermediate populations. Second, a test of sharing of alleles, particularly rare alleles, can show whether outbreaks are related to each other rather than arriving as independent samples from the core population. The shared-allele statistic also serves as a genetic distance measure that is appropriate for small samples. These methods were applied to data on a fruit fly pest species, Bactrocera tryoni, which is quarantined from some horticultural areas in Australia. We concluded that the outbreaks in the quarantine zone came from a heterogeneous set of genetically differentiated populations, possibly ones that overwinter in the vicinity of the quarantine zone.

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Differential Tropism in Roots and Shoots of Resistant and Susceptible Cassava (Manihot esculenta Crantz) Infected by Cassava Brown Streak Viruses

Cells ◽

10.3390/cells10051221 ◽

2021 ◽

Vol 10 (5) ◽

pp. 1221

Author(s):

Samar Sheat ◽

Paolo Margaria ◽

Stephan Winter

Keyword(s):

Virus Replication ◽

Central Africa ◽

Streak Virus ◽

Virus Infections ◽

Long Distance ◽

Manihot Esculenta Crantz ◽

Cassava Brown Streak Virus ◽

Cassava Brown Streak Disease ◽

Long Distance Movement ◽

Brown Streak

Cassava brown streak disease (CBSD) is a destructive disease of cassava in Eastern and Central Africa. Because there was no source of resistance in African varieties to provide complete protection against the viruses causing the disease, we searched in South American germplasm and identified cassava lines that did not become infected with the cassava brown streak viruses. These findings motivated further investigations into the mechanism of virus resistance. We used RNAscope® in situ hybridization to localize cassava brown streak virus in cassava germplasm lines that were highly resistant (DSC 167, immune) or that restricted virus infections to stems and roots only (DSC 260). We show that the resistance in those lines is not a restriction of long-distance movement but due to preventing virus unloading from the phloem into parenchyma cells for replication, thus restricting the virus to the phloem cells only. When DSC 167 and DSC 260 were compared for virus invasion, only a low CBSV signal was found in phloem tissue of DSC 167, indicating that there is no replication in this host, while the presence of intense hybridization signals in the phloem of DSC 260 provided evidence for virus replication in companion cells. In neither of the two lines studied was there evidence of virus replication outside the phloem tissues. Thus, we conclude that in resistant cassava lines, CBSV is confined to the phloem tissues only, in which virus replication can still take place or is arrested.

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