• Journal of Plant Biotechnology
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• v.30 no.2
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• pp.129-133
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• 2003

The factors for symptom development caused by Beat curly top virus(BCTV) have been analyzed by using a molecular genetic approach based on expressing BCTV encoded proteins in transgenic plants. BCTV open reading frame (ORF) L4 expression in transgenic Arabidopsis resulted in abnormal plant development and the production of callus inflorescence stems and bumpy trichomes, confiming that this gene alone is a primary symptom determinant. The L4 gene expression by northern hybridization in transgenic plants and a range of phenotypes were analyzed.

• Journal of Plant Biotechnology
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• v.35 no.4
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• pp.337-343
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• 2008

We generated transgenic tomato plants with Arabidopsis thaliana $H^+$/cation exchanger gene (C4X4) by Agrobactrium-mediated transformation. We confirmed transgene copy number and transcription by Southern and Northern blot analyses. The intact CAX4-expressing tomato (Lycopersicon esculentum) fruits contained 63-71% more calcium ($Ca^{2+}$) than wild-type fruits. Moreover, ectopic expression of C4X4 in tomato fruits did not show any significant increase of the four kinds of metallic cations analyzed ($Mg^{2+}$, $Fe^{2+}$, $Mn^{2+}$, and $Cu^{2+})$. The C4X4-expressing tomato plants including their fruits did not show any morphological alternations during whole growth period. These results suggest the enhanced Ca-substrate specificity of CAX4 exchanger in tomato. Therefore, intact CAX4 exchanger can be a useful tool for $Ca^{2+}$ nutrient enrichment of tomato fruits with reduced accumulation of undesirable cations.