Ruvbl1 silencing affects reproduction of the corn planthopper, Peregrinus maidis.

Ruvbl1 (also known as TIP49, Pontin) encodes an ATPase of the AAA+ protein superfamily involved in several cellular functions, including chromatin remodeling, control of transcription, and cellular development (motility, growth, and proliferation). While its role has been well established in model organisms including vertebrates and invertebrates (e.g.

RNAi-mediated knockdown of exportin 1 negatively affected ovary development, survival and maize mosaic virus accumulation in its insect vector Peregrinus maidis.

Exportin 1 (XPO1) is the major karyopherin-β nuclear receptor mediating the nuclear export of hundreds of proteins and some classes of RNA and regulates several critical processes in the cell, including cell-cycle progression, transcription and translation. Viruses have co-opted XPO1 to promote nucleocytoplasmic transport of viral proteins and RNA. Maize mosaic virus (MMV) is a plant-infecting rhabdovirus transmitted in a circulative propagative manner by the corn planthopper, Peregrinus maidis.

Specific Nucleotides in the Common Region of the Begomovirus Tomato Rugose Mosaic Virus (ToRMV) Are Responsible for the Negative Interference over Tomato Severe Rugose Virus (ToSRV) in Mixed Infection.

Mixed infection between two or more begomoviruses is commonly found in tomato fields and can affect disease outcomes by increasing symptom severity and viral accumulation compared with single infection. Viruses that affect tomato include tomato severe rugose virus (ToSRV) and tomato rugose mosaic virus (ToRMV). Previous work showed that in mixed infection, ToRMV negatively affects the infectivity and accumulation of ToSRV.

Plant virology.

The first infectious agent to bear the name 'virus' was described in 1898: a plant pathogen called tobacco mosaic virus that infects a wide range of plants and results in a yellow mosaic of the leaves. Since then, the study of plant viruses has facilitated new discoveries in both virology and plant biology. Traditionally, research has focused on viruses that cause severe disease in plants used for human and animal food or recreation.

Begomovirus populations in single plants are complex and may include both well-adapted and poorly-adapted viruses.

Begomoviruses (single-stranded DNA plant viruses transmitted by whiteflies) are economically important pathogens causing epidemics worldwide. Tomato-infecting begomoviruses emerged in Brazil in the 1990's following the introduction of Bemisia tabaci Middle East-Asia Minor 1. It is believed that these viruses evolved from indigenous viruses infecting non-cultivated hosts.

Rescue of the first alphanucleorhabdovirus entirely from cloned complementary DNA: An efficient vector for systemic expression of foreign genes in maize and insect vectors.

Recent reverse genetics technologies have enabled genetic manipulation of plant negative-strand RNA virus (NSR) genomes. Here, we report construction of an infectious clone for the maize-infecting Alphanucleorhabdovirus maydis, the first efficient NSR vector for maize. The full-length infectious clone was established using agrobacterium-mediated delivery of full-length maize mosaic virus (MMV) antigenomic RNA and the viral core proteins (nucleoprotein N, phosphoprotein P, and RNA-directed RNA polymerase L) required for viral transcription and replication into Nicotiana benthamiana.

Assessing the diversity of whiteflies infesting cassava in Brazil.

Background: The necessity of a competent vector for transmission is a primary ecological factor driving the host range expansion of plant arthropod-borne viruses, with vectors playing an essential role in disease emergence. Cassava begomoviruses severely constrain cassava production in Africa. Curiously, begomoviruses have never been reported in cassava in South America, the center of origin for this crop.

Evolutionary dynamics of bipartite begomoviruses revealed by complete genome analysis.

Several key evolutionary events marked the evolution of geminiviruses, culminating with the emergence of divided (bipartite) genomes represented by viruses classified in the genus Begomovirus. This genus represents the most abundant group of multipartite viruses, contributing significantly to the observed abundance of multipartite species in the virosphere. Although aspects related to virus-host interactions and evolutionary dynamics have been extensively studied, the bipartite nature of these viruses has been little explored in evolutionary studies.

Ever-increasing viral diversity associated with the red imported fire ant Solenopsis invicta (Formicidae: Hymenoptera).

Background: Advances in sequencing and analysis tools have facilitated discovery of many new viruses from invertebrates, including ants. Solenopsis invicta is an invasive ant that has quickly spread worldwide causing significant ecological and economic impacts. Its virome has begun to be characterized pertaining to potential use of viruses as natural enemies.

Two new begomoviruses infecting tomato and Hibiscus sp. in the Amazon region of Brazil.

Two begomoviruses were isolated in the northern Brazilian state of Pará, infecting non-cultivated Hibiscus sp. and cultivated tomato (Solanum lycopersicum). The complete genomes (DNA-A and DNA-B) of the two viruses showed the typical organization of New World bipartite begomoviruses.

Complete genome sequences of two gemycircularviruses associated with non-cultivated plants in Brazil.

Gemycircularviruses (genus Gemycircularvirus, family Genomoviridae) are single-stranded DNA viruses that are spread around the world in association with several organisms and environments. In this work, we identified two gemycircularviruses associated with two non-cultivated plants in Brazil, Momordica charantia and Euphorbia heterophylla. Both viruses display the general genome structure of gemycircularviruses.

Genetic variability and population structure of the New World begomovirus Euphorbia yellow mosaic virus.

The emergence of begomoviruses (whitefly-transmitted viruses classified in the genus Begomovirus, family Geminiviridae) in Brazil probably occurred by horizontal transfer from non-cultivated plants after the introduction of Bemisia tabaci MEAM1. The centre of diversity of Euphorbia heterophylla (Euphorbiaceae) is located in Brazil and Paraguay, where it is an invasive species in soybean and other crops. Reports of possible begomovirus infection of E.

Two new begomoviruses that infect non-cultivated malvaceae in Brazil.

A high diversity of begomoviruses that infect non-cultivated plants has been noted in Brazil. Here, we report the complete sequences of two new species of bipartite begomoviruses from Sida sp. plants collected in the state of Piauí, northeastern Brazil.

Contrasting genetic structure between two begomoviruses infecting the same leguminous hosts.

Begomoviruses are whitefly-transmitted, ssDNA plant viruses and are among the most damaging pathogens causing epidemics in economically important crops worldwide. Wild/non-cultivated plants play a crucial epidemiological role, acting as begomovirus reservoirs and as 'mixing vessels' where recombination can occur. Previous work suggests a higher degree of genetic variability in begomovirus populations from non-cultivated hosts compared with cultivated hosts.

Begomovirus diversity in tomato crops and weeds in Ecuador and the detection of a recombinant isolate of rhynchosia golden mosaic Yucatan virus infecting tomato.

Viral diseases caused by begomoviruses are of economic importance due to their adverse effects on the production of tropical and subtropical crops. In Ecuador, despite reports of significant infestations of Bemisia tabaci in the late 1990s, only very recently has a begomovirus, tomato leaf deformation virus (ToLDeV, also present in Peru), been reported in tomato. ToLDeV is the first monopartite begomovirus discovered that originated in the Americas, and its presence in Ecuador highlights the need for a wider survey of tomato-infecting begomoviruses in this country.

Brazilian begomovirus populations are highly recombinant, rapidly evolving, and segregated based on geographical location.

The incidence of begomovirus infections in crop plants sharply increased in Brazil during the 1990s following the introduction of the invasive B biotype of the whitefly vector, Bemisia tabaci. It is believed that this biotype transmitted begomoviruses from noncultivated plants to crop species with greater efficiency than indigenous B. tabaci biotypes.

Synonymous site variation due to recombination explains higher genetic variability in begomovirus populations infecting non-cultivated hosts.

Begomoviruses are ssDNA plant viruses that cause serious epidemics in economically important crops worldwide. Non-cultivated plants also harbour many begomoviruses, and it is believed that these hosts may act as reservoirs and as mixing vessels where recombination may occur. Begomoviruses are notoriously recombination-prone, and also display nucleotide substitution rates equivalent to those of RNA viruses.