• Plant Breeding and Biotechnology
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• 제2권3호
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• pp.289-300
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• 2014

A tissue-specific and developmentally expressed gene was isolated from Chinese cabbage (Brassica rapa L. ssp. pekinensis), designated BrREF (B. rapa Rubber elongation factor). BrREF transcripts were expressed at high levels in seedlings and at low levels in flower buds and roots. To study the activity of this promoter, the 2.2 kb upstream sequence of BrREF gene was fused to a β-glucuronidase (GUS) reporter gene and was introduced into Arabidopsis thaliana and B. napus by Agrobacterium-mediated transformation. Strong expression of GUS driven by the BrREF promoter was detected in the cotyledons and hypocotyls of transgenic plant seedlings, but GUS expression was weak in roots, excluding the root tips. GUS expression in the cotyledons and hypocotyls decreased dramatically as the seedlings matured and was not detected in the tissues of mature plants. During floral development, GUS expression was observed in immature anthers. These findings suggest that the BrREF promoter can modulate the tissue-specific and developmental expression of gene at the early stages of growth and development.

• Plant Biotechnology Reports
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• 제5권4호
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• pp.323-329
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• 2011

MuSI, a gene that corresponds to a domain that contains the rubber elongation factor (REF), is highly homologous to many stress-related proteins in plants. Since MuSI is up-regulated in the roots of plants treated with cadmium or copper, the involvement of MuSI in cadmium tolerance was investigated in this study. Escherichia coli cells overexpressing MuSI were more resistant to Cd than wild-type cells transfected with vector alone. MuSI transgenic plants were also more resistant to Cd. MuSI transgenic tobacco plants absorbed less Cd than wild-type plants. Cd translocation from roots to shoots was reduced in the transgenic plants, thereby avoiding Cd toxicity. The number of short trichomes in the leaves of wild-type tobacco plants was increased by Cd treatment, while this was unchanged in MuSI transgenic tobacco. These results suggest that MuSI transgenic tobacco plants have enhanced tolerance to Cd via reduced Cd uptake and/or increased Cd immobilization in the roots, resulting in less Cd translocation to the shoots.