Characterization of grapefruit plants (Citrus paradisi Macf.) transformed with citrus tristeza closterovirus genes

• Published in: Plant cell reports Vol. 21; no. 5; pp. 421 - 428
• Main Authors: FEBRES, V. J, NIBLETT, C. L, LEE, R. F, MOORE, G. A
• Format: Journal Article
• Language: English
• Published: Berlin Springer 2003; Springer Nature B.V
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; Blotting, Southern; Blotting, Western; Capsid Proteins - genetics; Capsid Proteins - metabolism; Citrus paradisi - genetics; Closterovirus - genetics; DNA, Plant - genetics; Fruits; Fundamental and applied biological sciences. Psychology; Genetics and breeding of economic plants; Glucuronidase - genetics; Glucuronidase - metabolism; Pest resistance; Plant pathogens; Plants, Genetically Modified - genetics; Plasmids - genetics; RNA Replicase - genetics; RNA Replicase - metabolism; Transformation, Genetic; Transgenic plants; Varietal selection. Specialized plant breeding, plant breeding aims; Citrus tristeza virus; Pathogen-mediated resistance; Stability; Genetic transformation; Plant pathogen; Citrus fruit; Rutaceae; Citrus paradisi; Virus; Characterization; Disease resistance; Sensitivity resistance; Gene; Closteroviridae; Dicotyledones; Angiospermae; Genetic improvement; Genetic identification; Grapefruit; Spermatophyta; Transgenic plant; Closterovirus
• ISSN: 0721-7714; 1432-203X
• DOI: 10.1007/s00299-002-0528-y

Grapefruit (Citrus paradisi Macf. cv Duncan) plants were transformed with several sequences from citrus tristeza closterovirus (CTV) that varied in terms of position in the CTV genome and virus strain origin in an attempt to obtain resistant plants. The sequences included the capsid protein gene from three different strains, a nontranslatable version of the capsid protein gene, the replicase (RdRp), the minor capsid protein (p27), a highly transcribed gene of unknown function (p20) and the more conserved 3' end of the genomic RNA. Transgenic plants were generated from all of the constructs, except from the p20 and p27 genes. Southern and Western blot analyses demonstrated that stably transformed grapefruit plants were obtained and that at least some transgenes were expressed. In a first effort at virus challenge, 25 transgenic lines were graft inoculated with a severe strain of CTV. Although some transgenic plants averaged lower titers of virus than controls, there was great variability in titer in both controls and transgenic plants, and all were apparently susceptible to the virus.