植物学技术

Identification of the roles of replication factors represents one of the major frontiers in current virus research. Among plant viruses, the positive-stranded (+) RNA viruses are the largest group and the most widespread. The central step in the infection cycles of (+) RNA viruses is RNA replica ...

RNA silencing suppressors, developed by plant viruses, are potent arms in the arm race between plant and invading viruses. In higher plants, these proteins efficiently inhibit RNA silencing, which has evolved to defend plants against viral infection in addition to regulation of gene expr ...

The technique described was developed for the separation of begomovirus DNA. DNA products resulting from and during geminiviral replication are characterized by the application of strand-specific separation and identification by strand-specific DNA probing of Southern bl ...

Most phytoviruses rely on vectors for their spread and survival. Although a great variety of virus vectors have been described, there are relatively few different mechanisms mediating virus transmission by vectors: virions can either be internalized into vector cells where replica ...

Viroids, as a consequence of not encoding any protein, are extremely dependent on their hosts. Replication of these minimal genomes, composed exclusively by a circular RNA of 246–401 nt, occurs in the nucleus (family Pospiviroidae) or in the chloroplast (family Avsunviroidae) by an RNA-bas ...

The Begomovirus genus is the largest genus of the Geminiviridae family and comprises the whitefly transmitted geminiviruses that infect dicotyledonous plants. They can be either mono or bipartite. In this chapter, we describe the cloning of begomovirus replication modules and the su ...

The ability to combine nucleic acid hybridisation or immunospecific reactions with structural and ultrastructural analysis of virus-infected tissues has provided the opportunity to resolve the spatial details of infection with respect to the production of virus-specific pr ...

The interaction between viral polymerases and their cognate RNAs is vital to regulate the timing and abundance of viral replication products. Despite this, only minimal detailed information is available for the interaction between viral polymerases and cognate RNAs. We study the bio ...

Small RNAs such as small interfering RNAs (siRNAs) and microRNAs (miRNAs) play crucial roles in establishing general host defense mechanisms against viral infections in plants and the development of disease symptoms. Understanding these fundamental processes requires the sen ...

During their infection in plants, viruses can form double stranded (ds) RNA structures. These dsRNAs can be recognized by plants as “aberrant” signals and short interfering RNA (siRNA) molecules of 19–25 nt will be produced with sequences derived from the viral source. Knowledge about antiv ...

Analysis of viral RNA encapsidation assay provides a rapid means of assaying which of the progeny RNA are competent for packaging into stable mature virions. Generally, a parallel analysis of total RNA and RNA obtained from purified virions is advisable for accurate interpretation of the re ...

Single-stranded RNA plant viruses not only code for viral proteins within their RNA genomes, they often maintain elaborate RNA secondary structures. These structures can be integral to a variety of viral processes, such as viral translation, genome replication, subgenomic mRNA trans ...

Positive-strand RNA viruses often use noncanonical strategies to usurp the host translational machinery for their own benefit. These strategies have been analyzed using transient expression assays in the absence of replication, with reporter genes replacing viral genes. A sensi ...

Replication of the viral RNA genome performed by the viral replicase is the central process during the viral infection cycle (Nagy and Pogany, see earlier chapter four). Most RNA viruses assign one or more proteins translated from their own genomes for assembling the viral replicase complex, w ...

Plant RNA viruses exploit nonorthodox strategies, such as the use of internal ribosomal entry sites (IRES), to express multiple genes from a single RNA species. IRES elements have been reported in tobacco etch virus (TEV), crucifer infecting tobamovirus (crTMV), hibiscus chlorotic ring ...

The genomes of many plant viruses contain translation-enhancing sequences that allow them to compete successfully with host messenger RNAs for the translation machinery. Identification of translation enhancer elements is valuable, both to gain understanding of virus gene exp ...

RNA–protein interactions control viral RNA replication, transcription, translation, and particle assembly. Progress toward understanding the functional significance of RNA–protein complexes in the viral life cycle is hindered by the lack of high resolution structural inf ...

Most plant viruses move between plant cells with the help of their movement proteins (MPs). MPs are multifunctional proteins, and one of their functions is almost invariably binding to nucleic acids. Presumably, the MP—nucleic acid interaction is directly involved in formation of nucleo ...

Movement proteins (MPs) are virally encoded factors that mediate transport of viral nucleic acid between plant cells. Many MPs are able to move between cells themselves. This feature serves as the basis for evaluation of the transport activity of individual MPs. MPs are transiently express ...

RNA silencing is an evolutionarily conserved system that functions as an antiviral mechanism in higher plants and animals. To counteract RNA silencing, viruses evolved silencing suppressors that interfere with siRNA guided RNA silencing pathway. We used the heterologous Drosop ...