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Overexpression of UV-DAMAGED DNA BINDING PROTEIN 1 links plant development and phytonutrient accumulation in high pigment-1 tomato.

Azari R, Reuveni M, Evenor D, Nahon S, Shlomo H, Chen L, Levin I - J. Exp. Bot. (2010)

Bottom Line: However, whole-plant overexpression of DDB1, required to substantiate its effects on seedling and plant development and to couple them with fruit phenotypes, has heretofore been unsuccessful.This overexpression resulted in statistically significant reversion to the non-mutant developmental phenotypes, including more than a full quantitative reversion.Cumulatively, these results provide the missing link between DDB1 and its effects on tomato plant development.

View Article: PubMed Central - PubMed

Affiliation: Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, PO Box 6, Bet Dagan 50250, Israel.

ABSTRACT
Fruits of tomato plants carrying the high pigment-1 mutations hp-1 and hp-1(w) are characterized by an increased number of plastids coupled with enhanced levels of functional metabolites. Unfortunately, hp-1 mutant plants are also typified by light-dependent retardation in seedling and whole-plant growth and development, which limits their cultivation. These mutations were mapped to the gene encoding UV-DAMAGED DNA BINDING PROTEIN 1 (DDB1) and, recently, fruit-specific RNA interference studies have demonstrated an increased number of plastids and enhanced carotenoid accumulation in the transgenic tomato fruits. However, whole-plant overexpression of DDB1, required to substantiate its effects on seedling and plant development and to couple them with fruit phenotypes, has heretofore been unsuccessful. In this study, five transgenic lines constitutively overexpressing normal DDB1 in hp-1 mutant plants were analysed. Eleven-day-old seedlings, representing these lines, displayed up to approximately 73- and approximately 221-fold overexpression of the gene in hypocotyls and cotyledons, respectively. This overexpression resulted in statistically significant reversion to the non-mutant developmental phenotypes, including more than a full quantitative reversion. This reversion of phenotypes was generally accompanied by correlated responses in chlorophyll accumulation and altered expression of selected light signalling genes: PHYTOCHROME A, CRYPTOCHROME 1, ELONGATED HYPOCOTYL 5, and the gene encoding CHLOROPHYLL A/B-BINDING PROTEIN 4. Cumulatively, these results provide the missing link between DDB1 and its effects on tomato plant development.

Show MeSH
Light intensity recorded, relative to wavelength, under white light and under the yellow screen in the controlled growth chamber.
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fig1: Light intensity recorded, relative to wavelength, under white light and under the yellow screen in the controlled growth chamber.

Mentions: The seedling experiment was carried out in an environmentally controlled growth chamber (16 h light/8 h dark) at of 25±1 °C. Two blocks were used in a randomized block design, with 20 seedlings per plot comprised of 240 ml pots filled with planting soil (Shaham Givat Ada Ltd, Givat Ada, Israel). During the experiment, seeds of the five transgenic lines as well as the three control lines were allowed to germinate and grow for 11 d under two photomorphogenic conditions, i.e. white light and under a yellow optical screen, and under skotomorphogenic conditions (complete darkness). The yellow screen prevented the transmission of light below a wavelength of 500 nm (Fig. 1). Germination and seedling growth under these broad-range red light conditions has been shown to result in an exaggeration of the differences in hypocotyl development between hp mutants and normal seedlings (Mochizuki and Kamimura, 1984; Adamse et al., 1989; Peters et al., 1989, 1992; Kerckhoffs et al., 1997). The light intensities used in this experiment in relation to the spectral wavelengths are presented in Fig. 1 and were measured with an Apogee pyranometer CS-300L (Campbell Scientific, North Logan, UT, USA).


Overexpression of UV-DAMAGED DNA BINDING PROTEIN 1 links plant development and phytonutrient accumulation in high pigment-1 tomato.

Azari R, Reuveni M, Evenor D, Nahon S, Shlomo H, Chen L, Levin I - J. Exp. Bot. (2010)

Light intensity recorded, relative to wavelength, under white light and under the yellow screen in the controlled growth chamber.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC2921201&req=5

fig1: Light intensity recorded, relative to wavelength, under white light and under the yellow screen in the controlled growth chamber.
Mentions: The seedling experiment was carried out in an environmentally controlled growth chamber (16 h light/8 h dark) at of 25±1 °C. Two blocks were used in a randomized block design, with 20 seedlings per plot comprised of 240 ml pots filled with planting soil (Shaham Givat Ada Ltd, Givat Ada, Israel). During the experiment, seeds of the five transgenic lines as well as the three control lines were allowed to germinate and grow for 11 d under two photomorphogenic conditions, i.e. white light and under a yellow optical screen, and under skotomorphogenic conditions (complete darkness). The yellow screen prevented the transmission of light below a wavelength of 500 nm (Fig. 1). Germination and seedling growth under these broad-range red light conditions has been shown to result in an exaggeration of the differences in hypocotyl development between hp mutants and normal seedlings (Mochizuki and Kamimura, 1984; Adamse et al., 1989; Peters et al., 1989, 1992; Kerckhoffs et al., 1997). The light intensities used in this experiment in relation to the spectral wavelengths are presented in Fig. 1 and were measured with an Apogee pyranometer CS-300L (Campbell Scientific, North Logan, UT, USA).

Bottom Line: However, whole-plant overexpression of DDB1, required to substantiate its effects on seedling and plant development and to couple them with fruit phenotypes, has heretofore been unsuccessful.This overexpression resulted in statistically significant reversion to the non-mutant developmental phenotypes, including more than a full quantitative reversion.Cumulatively, these results provide the missing link between DDB1 and its effects on tomato plant development.

View Article: PubMed Central - PubMed

Affiliation: Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, PO Box 6, Bet Dagan 50250, Israel.

ABSTRACT
Fruits of tomato plants carrying the high pigment-1 mutations hp-1 and hp-1(w) are characterized by an increased number of plastids coupled with enhanced levels of functional metabolites. Unfortunately, hp-1 mutant plants are also typified by light-dependent retardation in seedling and whole-plant growth and development, which limits their cultivation. These mutations were mapped to the gene encoding UV-DAMAGED DNA BINDING PROTEIN 1 (DDB1) and, recently, fruit-specific RNA interference studies have demonstrated an increased number of plastids and enhanced carotenoid accumulation in the transgenic tomato fruits. However, whole-plant overexpression of DDB1, required to substantiate its effects on seedling and plant development and to couple them with fruit phenotypes, has heretofore been unsuccessful. In this study, five transgenic lines constitutively overexpressing normal DDB1 in hp-1 mutant plants were analysed. Eleven-day-old seedlings, representing these lines, displayed up to approximately 73- and approximately 221-fold overexpression of the gene in hypocotyls and cotyledons, respectively. This overexpression resulted in statistically significant reversion to the non-mutant developmental phenotypes, including more than a full quantitative reversion. This reversion of phenotypes was generally accompanied by correlated responses in chlorophyll accumulation and altered expression of selected light signalling genes: PHYTOCHROME A, CRYPTOCHROME 1, ELONGATED HYPOCOTYL 5, and the gene encoding CHLOROPHYLL A/B-BINDING PROTEIN 4. Cumulatively, these results provide the missing link between DDB1 and its effects on tomato plant development.

Show MeSH