Abstract
Protein P6 is the main symptom determinant of cauliflower mosaic virus (CaMV), and transgene-mediated expression in Arabidopsis induces a symptom-like phenotype in the absence of infection. Seeds of a P6-transgenic line, A7, were mutagenized by γ-irradiation and M2 seedlings were screened for mutants that suppressed the phenotype of chlorosis and stunting. We identified four mutants that were larger and less chlorotic than the A7 parent but which contained an intact and transcriptionally active transgene. The two mutants with the strongest suppression phenotype, were recessive and allelic. The transgene was eliminated by back-crossing with wild-type Arabidopsis. In progeny lines that were homozygous for the putative suppressor mutation the proportion of plants becoming infected following inoculation with CaMV was 40% that of wild-type, although in plants that did become infected, levels of virus DNA in mutants and wild-type did not differ significantly. Symptoms in the mutants were milder and delayed although this was somewhat dependent on the virus isolate. This phenotype was inherited stably. Both mutant alleles showed a partially ethylene-insensitive phenotype in an ethylene triple response assay. P6-transgenic plants were also almost completely insensitive to ethylene in the triple response assay. We suggest that the chlorosis and stunting in P6-transgenic and CaMV-infected plants are dependent on interactions between P6 and components involved in ethylene signalling, and that the suppressor gene product may function to augment these interactions.
Similar content being viewed by others
References
Agama, K., Beach, S., Schoelz, J. and Leisner, S. M. 2002. The 50 third of Cauliflower mosaic virus gene VI conditions resistance breakage in Arabidopsis ecotype tsu-0 Phytopathology 92: 190–196.
Aranda, M. and Maule, A. 1998. Virus-induced host gene shutoff in animals and plants. Virology 243: 261–267.
Baughman, G. A., Jacobs, J. D. and Howell, S. H. 1988. Cauli-flower mosaic-virus gene VI produces a symptomatic phenotype in transgenic tobacco plants. Proc. Natl. Acad. Sci. USA. 85: 733–737.
Berrocal-Lobo, M., Molina, A. and Solano, R. 2002. Constitutive expression of ETHYLENE-RESPONSE-FACTOR1 in Arabidopsis confers resistance to several necrotrophic fungi. Plant J. 29: 23–32.
Bleecker, A. B. and Kende, H. 2000. Ethylene: a gaseous signal molecule in plants. Annu. Rev. Cell Dev. Biol. 16: 1–20.
Broglio, E. P. 1995. Mutational analysis of cauliflower mosaic virus gene VI-changes in host-range, symptoms, and discovery of transactivation-positive, noninfectious mutants. Mol. Plant-Microbe Interact. 8: 755–760.
Carrington, J. C. and Whitham, S. A. 1998. Viral invasion and host defense: strategies and counter-strategies. Curr. Opin. Plant Biol. 1: 336–341.
Cecchini, E., Al Kaff, N. S., Bannister, A., Giannakou, M. E., McCallum, D. G., Maule, A. J., Milner, J. J. and Covey, S. N. 1998a. Pathogenic interactions between variants of cauli-flower mosaic virus and Arabidopsis thaliana. J. Exp. Bot. 49: 731–737.
Cecchini, E., Geri, C., Love, A. J., Coupland, G., Covey, S. N. and Milner, J. J. 2002. Mutations that delay flowering in Arabidopsis de-couple symptom response from cauliflower mosaic virus accumulation during infection. Mol. Plant Pathol. 3: 81–90.
Cecchini, E., Gong, Z. H., Geri, C., Covey, S. N. and Milner, J. J. 1997. Transgenic Arabidopsis lines expressing gene VI from cauliflower mosaic virus variants exhibit a range of symptom-like phenotypes and accumulate inclusion bodies. Mol. Plant-Microbe Interact. 10: 1094–1101.
Cecchini, E., Mulligan, B. J., Covey, S. N. and Milner, J. J. 1998b. Characterization of gamma irradiation-induced deletion mutations at a selectable locus in Arabidopsis. Mutat. Res. 401: 199–206.
Covey, S. N. and Hull, R. 1981. Transcription of cauliflower mosaic-virus DNA-detection of transcripts, properties, and location of the gene encoding the virus inclusion body protein. Virology 111: 463–474.
Covey, S. N., McCallum, D. G., Turner, D. S., Al Kaff, N. S., Dale, P., Cecchini, E. and Milner, J. J. 2000. Pararetroviruscrucifer interactions: attack and defence or modus vivendi. Mol. Plant Pathol. 1: 77–86.
Covey, S. N. and Turner, D. S. 1991. Comparison of viral nucleic-acid intermediates at early and late stages of cauli-flower mosaic-virus infection suggests a feedback regulatory mechanism. J. Gen. Virol. 72: 2603–2606.
Delseny, M. and Hull, R. 1983. Isolation and characterization of faithful and altered clones of the genomes of cauliflower mosaic-virus isolates Cabb B-JI, CM4–184, and Bari-1. Plasmid 9: 31–41.
Devadas, S. K., Enyedi, A. and Raina, R. 2002. The Arabidopsis hrl1 mutation reveals novel overlapping roles for salicylic acid, jasmonic acid and ethylene signalling in cell death and defence against pathogens. Plant J. 30: 467–480.
Geraats, B. P. J., Bakker, P. A. H. M. and Van Loon, L. C. 2002. Ethylene insensitivity impairs resistance to soilborne pathogens in tobacco and Arabidopsis thaliana. Mol. Plant-Microbe Interact. 15: 1078–1085.
Geri, C., Cecchini, E., Giannakou, M. E., Covey, S. N. and Milner, J. J. 1999. Altered patterns of gene expression in Arabidopsis elicited by cauliflower mosaic virus (CaMV) infection and by a CaMV gene VI transgene. Mol. Plant-Microbe Interact. 12: 377–384.
Havelda, Z. and Maule, A. J. 2000. Complex spatial responses to cucumber mosaic virus infection in susceptible Cucurbita pepo cotyledons. Plant Cell 12: 1975–1985.
Hirsch, J., Deslandes, L., Feng, D. X., Balague, C. and Marco, Y. 2002. Delayed symptom development in ein2–1, an Arabidopsis ethylene-insensitive mutant, in response to bacterial wilt caused by Ralstonia solanacearum. Phytopathology 92: 1142–1148.
Krake, L. R., Rezaian, M. A. and Dry, I. B. 1998. Expression of the tomato leaf curl geminivirus C4 gene produces viruslike symptoms in transgenic plants. Mol. Plant-. Microbe Interact. 11: 413–417.
Kunkel, B. N. and Brooks, D. M. 2002. Cross talk between signaling pathways in pathogen defense. Curr. Opin. Plant Biol. 5: 325–331.
Laval, V., Love, A. J., Barnes, S., Tomos, A. D., Hooks, M. A., Loake, G. J., Yun, B-W. and Milner, J. J. 2003. Host defence signalling is active during compatible infection of Arabidopsis by CaMV. VIIth Internat. Congress Plant Mol. Biol., Barcelona Abstract No. S25-S25: p365
Love, A. J. 2002. Host responses to infection by cauliflower mosaic virus. PhD Thesis, Glasgow University, Glasgow UK.
Nurnberger, T. and Scheel, D. 2001. Signal transmission in the plant immune response. Trends Plant Sci. 6: 372–379.
Palanichelvam, K., Cole, A. B., Shababi, M. and Schoelz, J. E. 2000. Agroinfiltration of Cauliflower mosaic virus gene VI elicits hypersensitive response in Nicotiana species. Mol. Plant-Microbe Interact. 13: 1275–1279.
Palanichelvam, K. and Schoelz, J. E. 2002. A comparative analysis of the avirulence and translational transactivator functions of gene VI of Cauliflower mosaic virus. Virology 293: 225–233.
Prins, M., Storms, M. M. H., Kormelink, R., DeHaan, P. and Goldbach, R. 1997. Transgenic tobacco plants expressing the putative movement protein of tomato spotted wilt tospovirus exhibit aberrations in growth and appearance. Transgenic Res. 6: 245–251.
Rigden, J. E., Krake, L. R., Rezaian, M. A. and Dry, I. B. 1994. ORF C4 Of tomato leaf curl geminivirus is a determinant of symptom severity. Virology 204: 847–850.
Rothnie, H. M., Chapdelaine, Y. and Hohn, T. 1994. Pararetroviruses and retroviruses-a comparative review of viral structure and gene-expression strategies. Adv. Virus Res. 44: 1–67.
Saunders, K., Wege, C., Veluthambi, K., Jeske, H. and Stanley, J. 2001. The distinct disease phenotypes of the common and yellow vein strains of Tomato golden mosaic virus are determined by nucleotide differences in the 30-terminal region of the gene encoding the movement protein. J. Gen. Virol. 82: 45–51.
Schoelz, J. E. and Shepherd, R. J. 1988. Host range control of cauliflower mosaic-virus. Virology 162: 30–37.
Stepanova, A. N. and Ecker, J. R. 2000. Ethylene signaling: from mutants to molecules. Curr. Opin. Plant Biol. 3: 353–360.
Stratford, R. and Covey, S. N. 1989. Segregation of cauliflower mosaic virus symptom genetic determinants. Virology 172: 451–459.
Ton, J., Davison, S., Van Loon, L. C. and Pieterse, C. M. J. 2001. Heritability of rhizobacteria-mediated induced systemic resistance and basal resistance in Arabidopsis. Eur. J. Plant Pathol. 107: 63–68.
Turner, D. S., McCallum, D. G. and Covey, S. N. 1996. Roles of the 35S promoter and multiple overlapping domains in the pathogenicity of the pararetrovirus cauliflower mosaic virus. J. Virol. 70: 5414–5421.
vanderWilk, F., Houterman, P., Molthoff, J., Hans, F., Dekker, B., vandenHeuvel, J., Huttinga, H. and Goldbach, R. 1997. Expression of the potato leafroll virus ORF0 induces viraldisease-like symptoms in transgenic potato plants. Mol. Plant.-Microbe Interact. 10: 153–159.
Wang, D. W. and Maule, A. J. 1995. Inhibition of host gene expression associated with plant-virus replication. Science 267: 229–231.
Weigel, D. and Glazebrook, J. 2002. Arabidopsis: a Laboratory Manual, Cold Spring Harbor Laboratory Press, Cold Spring Harbor, New York, pp. 66–68.
Whitham, S. A., Quan, S., Chang, H. S., Cooper, B., Estes, B., Zhu, T., Wang, X. and Hou, Y. M. 2003. Diverse RNA viruses elicit the expression of common sets of genes in susceptible Arabidopsis thaliana plants. Plant J. 33: 271–283.
Xue, C. Y., Tao, X. R. and Zhou, X. P. 2002. Coat protein gene and 30 non-coding region of tobacco mosaic virus and tomato mosaic virus are associated with viral pathogenesis in Nicotiana tabacum. Prog. Nat. Sci. 12: 679–683.
Yu, W. C., Murfett, J. and Schoelz, J. E. 2003. Differential induction of symptoms in Arabidopsis by P6 of Cauliflower mosaic virus. Mol. Plant. Microbe Interact. 16: 35–42.
Zhang, L, Hanada, K and Palukaitis, P. 1994. Mapping local and systemic symptom determinants of cucumber mosaic cucumovirus in tobacco. J. Gen. Virol. 75: 3185–3191.
Zijlstra, C. and Hohn, T. 1992. Cauliflower mosaic virus gene VI controls translation from dicistronic expression units in transgenic Arabidopsis plants. Plant Cell 4: 1471–1484.
Zijlstra, C., ScharerHernandez, N., Gal, S. and Hohn, T. 1996. Arabidopsis thaliana expressing the cauliflower mosaic virus ORF VI transgene has a late flowering phenotype. Virus Genes 13: 5–17.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Geri, C., Love, A.J., Cecchini, E. et al. Arabidopsis mutants that suppress the phenotype induced by transgene-mediated expression of cauliflower mosaic virus (CaMV) gene VI are less susceptible to CaMV-infection and show reduced ethylene sensitivity. Plant Mol Biol 56, 111–124 (2004). https://doi.org/10.1007/s11103-004-2649-x
Issue Date:
DOI: https://doi.org/10.1007/s11103-004-2649-x