Download or read book Cauliflower Mosaic Virus P6 Protein Interactions written by Lindy M. Lutz and published by . This book was released on 2014 with total page 232 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cauliflower mosaic virus (CaMV), one of the top ten viruses from a molecular plant pathology standpoint, is a plant pararetrovirus whose 8 kb circular double-stranded DNA genome encodes 7 different proteins (P1-P7). CaMV P6, encoded by gene VI has been implicated in a variety of functions such as: translational transactivation, host range control, symptom formation, host hypersensitive responses, RNA silencing suppressor activity, inclusion body (IB) formation and virus infectivity. Because of its multifunctional nature, P6 interacts with many host, and viral proteins including itself. P6 self-association appears to involve four domains (D1-D4). D3 has been implicated in viral infectivity and contains two RNA binding domains, separated by a highly conserved 34 amino acid spacer called D3b. CaMV mutants harboring a deletion of D3b are non-infectious, indicating its importance for viral propagation. To further analyze D3b, full-length P6 constructs were generated that harbored single amino acid substitutions within this region. In general, the mutants bound less efficiently to the individual P6 domains than wild type. Mutations near the amino-terminal end of D3b had a more detrimental effect on self-association domain binding than those near the central portion. Since P6 is an IB protein, we hypothesized that mutations in D3b may influence IB formation. P6 IBs are thought to start out as small aggregations of protein (most likely P6) and ribosomes. They acquire additional materials (viral proteins and nucleic acids) to enlarge to form small bodies. Small bodies are then thought to fuse together to form larger, mature IBs. All mutant P6s formed IBs when expressed as green fluorescent protein (GFP) fusions in transgenic cells. However, the mutant P6s that were most reduced in binding also showed decreased IB size. Hence, the mutations in D3b appear to affect the fusion of small IBs into larger ones. It is possible that IB size is important because it correlated with differences in virus host range. CaMV strain W260 has a much wider host range and more efficiently infects host plants when compared to the CM1841 isolated. Our most recent data show that CM1841 IBs are smaller than those formed by W260 P6. In addition, P6 mutants that showed decreased binding to self-association domains and smaller IB sizes also exhibited much lower total viral DNA levels in inoculated leaves. This was also reflected by systemic symptom formation. Hence, less efficient binding correlates with smaller IB size and reduced local and systemic infection for the mutants. Taken together, these data suggest that fusion of small IBs into larger ones is important for proper viral infections to occur and we have possibly identified mutants in this process. In addition, these data suggest that IB formation is required for viral infection rather than merely being a consequence of it. The CaMV genome encodes seven viral proteins including P6. P6 has been reported to interact with two other viral proteins in addition to itself. Therefore, we also examined P6 for its ability to interact with the other viral gene products. P6 was found to interact with the aphid transmission factor (P2), the virion-associated protein (P3), reverse transcriptase protein (P5), and the protein of unknown function (P7). P2 was previously reported to control the difference in IB stability between CM1841 and W260. Our data indicate that P2 from both viruses bound equally well to P6. The CM1841 P2 is less stable than its W260 counterpart. Taken together, this would suggest that the differences in IB stability for W260 and CM1841 mediated by P2 are due to variation in P2 protein stability rather than P6 binding. Binding of P6 to P3 could help the latter protein form complexes necessary for aphid transmission and virus cell-to-cell movement. P5 has a tri-partite structure with an N-terminal protease domain, a central reverse transcriptase (RT) and a C-terminal RNase H domain. Our pull-down results showed P6 could interact with full-length P5. Based on our preliminary pull-down analyses, P6 could bind inefficiently to the protease but more efficiently to the RT-RNase H (termed P5MC) portion of P5. Perhaps this interaction plays a role in P5 RT regulation. Interestingly, P5MC interactions with P5 showed a similar pattern to the P6 interactions. P5MC was able to self-associate well, but and interacted weakly with full-length P5 and the protease. P6 also interacted with P7, but the significance of this interaction is unknown. Perhaps P7 aids P6 in regulating an aspect of translational transactivation, but this is mere speculation. In addition, P6 can also interact with a variety of host factors. In collaboration with Dr. James Schoelz at the University of Missouri, we found three Arabidopsis proteins: CHUP1, C2CDMT, and FIT that interact with full-length P6. Interestingly, of the four domains involved in P6 self-association, only D2 and D4 bind to CHUP1 and C2CDMT. However, FIT was able to bind to all P6 self-association domains but best to D2. Given that it binds to other host factors, we might speculate that D2 of P6 maybe acts as a host interface domain. In summary P6 interacts with a large number of both viral and host proteins. P6 self-association is needed for proper IB formation and efficient infection. P6 interactions with each of the other viral proteins may be to modulate proper interactions of these proteins with their appropriate partners. Finally, P6 interactions with host factors may play a role in inhibiting host defenses, modulating systemic symptom formation, or mediating inter and intra cellular movement.

Download or read book Cauliflower Mosaic Virus ORF VI Protein written by Axel Himmelbach and published by . This book was released on 1995 with total page 88 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Association of the P6 Protein of Cauliflower Mosaic Virus with Plasmodesmata and Plasmodesmal Proteins written by Andres Rodriguez and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The P6 protein of Cauliflower mosaic virus (CaMV) is responsible for the formation of inclusion bodies (IBs), which are the site for viral gene expression, replication and virion assembly. Moreover, recent evidence indicates that ectopically expressed P6 IBs move in association with actin microfilaments. Since CaMV virions accumulate preferentially in P6 IBs, we hypothesized that P6 IBs have a role in delivering CaMV virions to the plasmodesmata. We recently discovered that the P6 protein interacted with a C2 calcium-dependent membrane targeting protein (designated AtSRC2-2) in a yeast two-hybrid screen and confirmed this interaction through co-immunoprecipitation and co-localization assays in the CaMV host, Nicotiana benthamiana. An AtSRC2-2 protein fused to RFP was localized to the plasma membrane and specifically associated with plasmodesmata. The AtSRC2-2-RFP fusion also co-localized with two proteins previously shown to associate with plasmodesmata: the host protein PDLP1 and the CaMV movement protein (MP). Since P6 IBs were found to co-localize with AtSCR2-2 and had previously been shown to interact with CaMV MP, we investigated whether a portion of the P6 IBs might also be associated with plasmodesmata. We examined the co-localization of P6-GFP IBs with PDLP1, the CaMV MP, and with aniline blue, a chemical stain for callose, and found that P6-GFP IBs were associated with each of these markers. Furthermore, a P6-RFP protein was co-immunoprecipitated with PDLP1-GFP. Our evidence that a portion of P6-GFP IBs associate with AtSRC2-2, PDLP1, and CaMV MP at plasmodesmata supports a model in which P6 IBs function to transfer CaMV virions directly to plasmodesmata.

Download or read book Identification and Analysis of Interactions Among Proteins of Cauliflower Mosaic Virus written by Shaddy N. Swade and published by . This book was released on 2007 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Molecular Expression of the Cauliflower Mosaic Virus Genome written by Joan Tellefsen Odell and published by . This book was released on 1981 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book National Proceedings written by and published by . This book was released on 2006 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: Compilation of 24 papers that were presented at the regional meetings of the forest and conservation nursery associations in the United States in 2005. The Western Forest and Conservation Nursery Association meeting was held at the Yarrow Resort Hotel and Conference Center in Park City, UT, on July 18 to 20. The meeting was hosted by the Utah Division of Forestry, Fire, and State Land , Lone Peak Nursery. Morning technical sessions were followed by field trips to restoration projects on the middle reach of the Provo River, McAffee Hill, and Dry Canyon, as well as tours of the Swaner Nature Preserve outside Park City, UT. Subject matter for the technical sessions included restoration outplanting, native species propagation, bareroot and container nursery culturing, greenhouse management, and gene conservation.

Download or read book The Coat Proteins of Cauliflower Mosaic Virus written by Peter James Hahn and published by . This book was released on 1981 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Proteins Associated with Cauliflower Mosaic Virus Infection and Their Intracellular Location written by Merle Wesley Shockey and published by . This book was released on 1979 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Cauliflower Mosaic Virus Transactivator and Its Interaction with the Host Translational Machinery written by Hyun-Sook Park and published by . This book was released on 2001 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Matthews Plant Virology written by Richard Ellis Ford Matthews and published by Gulf Professional Publishing. This book was released on 2002 with total page 1084 pages. Available in PDF, EPUB and Kindle. Book excerpt: It has been ten years since the publication of the third edition of this seminal text on plant virology, during which there has been an explosion of conceptual and factual advances. The fourth edition updates and revises many details of the previous editon, while retaining the important older results that constitute the field's conceptual foundation. Key features of the fourth edition include: * Thumbnail sketches of each genera and family groups * Genome maps of all genera for which they are known * Genetic engineered resistance strategies for virus disease control * Latest understanding of virus interactions with plants, including gene silencing * Interactions between viruses and insect, fungal, and nematode vectors * New plate section containing over 50 full-color illustrations.

Download or read book Arabidopsis written by Detlef Weigel and published by CSHL Press. This book was released on 2002 with total page 370 pages. Available in PDF, EPUB and Kindle. Book excerpt: The thale cress Arabidopsis thaliana is increasingly popular among plant scientists: it is small, easy to grow, and makes flowers, and the sequence of its small and simple genome was recently completed. This is the most complete and authoritative laboratory manual to be published on this model organism and the first to deal with genomic and proteomic approaches to its biology.

Download or read book The Cowpea Mosaic Virus Movement Protein written by C. M. Carvalho and published by . This book was released on 2003 with total page 87 pages. Available in PDF, EPUB and Kindle. Book excerpt: For systemic infection of a host plant, viruses multiply in the initially infected cell and spread to the neighbouring cells through plasmodesmata (cell-to-cell movement), to eventually reach the vascular system and use the phloem to spread to other plant parts (long-distance movement). To achieve cell-to-cell transport through plasmodesmata, these complex pores in the plant cell wall must be modulated to allow viral passage. Two major types of cell-to-cell transport have been described, movement of the viral genome in a non-encapsidated form, as exemplified by Tobacco mosaic virus (TMV), and?tubule-guided? movement of mature virus particles (virions), exemplified by Cowpea mosaic virus (CPMV). In both mechanisms one or more virally encoded movement proteins (MP) play an essential role in the targeting of infectious entities from the site of replication to the plasmodesmata, as well as in the subsequent modification of and transport through the modified pores. However, it is generally recognised that intercellular movement is a concerted effort of not only viral factors but also host factors, the knowledge of the latter being very scarce at the moment. With CPMV, the MP polymerises within the plasmodesmal pore into a transport tubule, through which mature virions then are delivered into the neighbouring uninfected cell. Identical tubules are also formed in single plant protoplasts that are infected with CPMV or transfected with the MP gene alone, hence, in the absence of cell wall and plasmodesmata. At the onset of the research presented in this thesis, no information about host proteins interacting with the CPMV MP was available. Such interactions were to be expected, for instance during the process of transport (targeting) of the MP from its site of synthesis to the periphery of the infected cell, the polymerisation process at the plasma membrane, and the structural modification of the plasmodesma. Thus, the research described in this thesis focused on the functioning of the CPMV MP with special emphasis on its interactions with virion proteins and host proteins. For initial studies on these interactions the property of the CPMV MP to assemble into tubules on single cell protoplasts was exploited in Chapter 2. Thus it was shown that virus particles residing in the tubule contain a single deviant species of the small coat protein (S CP) that is larger than the two forms of S CP (S-s and S-f) which are consistently found in virus present in the cytoplasm of infected cells. The nature of the deviation is not known, but the exclusive presence of this deviant S CP in virions that are being transported suggests that the S CP is in some way involved in cell-to-cell movement. Identification of host proteins in isolated tubule fractions by electrophoretic analysis was not successful, but a directed search for potential host proteins by Western blot analysis using specific antibodies indicated the presence of pectin methylesterase (PME) in the plasma membrane surrounding the tubule (Chapter 2). This protein has previously been implicated in cell-to-cell movement of other plant viruses, i.e. TMV, Cauliflower mosaic virus and Turnip vein clearing virus. The PME enzyme is involved in cell wall turnover and affects cell wall rigidity by modulating pH and ion balance. Such cell wall dynamics could be a necessity for the modification of the plasmodesmal pore to enable the insertion of a viral transport tubule. The interaction between the MP and virion proteins was further investigated in Chapter 3. Protein overlay assays and ELISA showed that the MP binds only to its homologous virions and that it is the large (L) coat protein which is involved in this binding. Considering also the deviation found in the S CP of virions within the transport tubules, it is conceivable that both CPs play a crucial but different role in the cell-to-cell movement of CPMV. A C-terminal deletion in MP, which in planta results in a mutant virus defective in cell-to-cell movement and producing tubules devoid of particles, also resulted in the abolishment of L CP binding, thus validating the in vitro binding approaches. The ability of the CPMV MP to bind nucleic acid and rNTP was analysed in Chapter 4. It is shown that MP binds rGTP but no other rNTPs, and by site-directed mutagenesis the GTP binding site was located within a sequence motif conserved among the MPs of tobamo- and comoviruses. The non-GTP-binding mutant MP exhibited disturbed intracellular targeting and tubule formation, suggesting that GTP binding may play a significant role in targeted transport and multimerization of the MP. It was also shown that the MP is capable of binding both ss-RNA and DNA, but not ds nucleic acids. The studies on possible interactions between CPMV MP and host (plasma membrane) proteins were extended in Chapter 5. To identify potential MP-binding host proteins, purified MP was used as a probe in overlay assays and affinity column chromatography to assess plasma membrane proteins for their affinity to the MP. In the blot overlay assays, candidate MP-binding proteins with apparent sizes of 34, 30 and 28 kDa were detected. Further analysis of the cowpea plasma membrane fraction using affinity chromatography also revealed a limited number of eight MP-binding proteins including again a 30 kDa protein band. Sequencing of the 30 kDa protein band revealed that it actually represented a mixture of two protein species, i.e. an aquaporin and a vacuolar-type ATPase. A possible role of these host proteins in viral MP functioning is discussed in Chapter 5. Finally, in the General Discussion (Chapter 6) the results obtained in this thesis research are discussed and integrated in a speculative model for the functioning of the CPMV MP, accommodating the different observed interactions with virion and host proteins.

Download or read book Gene to Code Cauliflower Mosaic Virus Inclusion Protein as Well as Plant Transformed by the Gene written by Hajime Takahashi and published by . This book was released on 1989 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Functional Analysis of the Cauliflower Mosaic Virus Movement Protein written by Marie-Christine Perbal and published by . This book was released on 1994 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Principles of Molecular Virology written by Alan Cann and published by Elsevier. This book was released on 2005-07-26 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Principles of Molecular Virology, Fourth Edition" provides an essential introduction to modern virology in a clear and concise manner. It is a highly enjoyable and readable text with numerous illustrations that enhance the reader's understanding of important principles. It contains new material on virus structure, virus evolution, zoonoses, bushmeat, SARS and bioterrorism. The standard version includes a CD-ROM with Flash animations, virtual interactive tutorials and experiments, self-assessment questions, useful online resources, along with the glossary, classification of subcellular infectious agents and history of virology.

Download or read book In Vivo and in Vitro Characterization of the Movement Protein of Cucumber Mosaic Virus written by Qiubo Li and published by . This book was released on 1995 with total page 304 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Involvement of the Cauliflower Mosaic Virus Gene VI Protein Product P62 in Determining Viral Host Range Disease Severity and Virus Accumulation written by Edwin Joseph Anderson and published by . This book was released on 1991 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt: