• Plant Resources
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• v.1 no.1
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• pp.33-37
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• 1998

Carotenoid compounds in embryos of wild-type(WT) and viviparous mutants of maize(Zea mays L.) were analyzed using high performance liquid ehromatography (HPLC) with a photodiode array detector. Zeaxanthin accumulates in WT embryos as the major carotenoid. Phytoene accumulates in vp2 and vp5. Phytofluene in w3 and ${\xi}$-carotene in the vp9 mutant embryos. This indicates that the vp2 and vp5 mutants impair phytoene desaturase from 15-cis-phytoene to 15-cis-phytofluene. The w3 mutant has neither an isomerase from 15-cis-phytofluene to all-trans-phytofuene nor phytofluene desaturase from phytofluene to ${\xi}$-carotene. The vp9 mutant does not have the ${\xi}$-carotene desaturase from ${\xi}$-carotene to lycopene. Our analysis shows that the terminal carotenoid. ${\gamma}$-carotene(${\beta},{\Psi}$-carotene), accumulates in the vp7 mutant embryos. The ${\varepsilon}$-carotene(${\varepsilon},{\varepsilon}$-carotene), a product of ${\delta}$-carotene(${\varepsilon},{\Psi}$-carotene) in some plants, however, has not been found in maize embryos. The vp7 mutant impairs a cyclization step from ${\gamma}$-carotene to both ${\beta}$-carotene and ${\alpha}$-carotene. We suggest that monocyclic ${\gamma}$-carotene is the sole precursor of both bicyclic ${\beta}$-carotene(${\beta},{\beta}$-carotene) and ${\alpha}$-carotene(${\beta},{\varepsilon}$-carotene) in maize.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.90-90
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• 2017

Regulation of seed dormancy is important in many grains to prevent pre-harvest sprouting. To identify and understand the gene related to seed dormancy regulation, we have screened for viviparous phenotypes of rice mutant lines generated by insertion of Ds transposon in a Korean Japonica cultivar (Dongjin) background. One of the mutants, which represented viviparous phenotype, was selected for further seed dormancy regulation studies and designated dor1. The dor1 mutant has single Ds insertion in the second exon of OsDor1 gene encoding glycine-rich protein. The seeds of dor1 mutant showed a higher germination potential and reduced abscisic acid (ABA) sensitivity compared to wild type Dongjin. Over-expression of Dor1 complements the viviparous phenotype of dor1 mutant, indicating that Dor1 function in seed dormancy regulation. Subcellular localization assay of Dor1-GFP fusion protein revealed that the OsDor1 protein mainly localized to membrane and the localization of OsDOR1 was influenced by presence of a giberelin (GA) receptor OsGID1. Further bimolecular fluorescence complementation (BiFC) analysis indicated that OsDOR1 interact with OsGID1. The combined results suggested that OsDOR1 regulates seed dormancy by interacting with OsGID1 in GA response. Additionally, expression of OsDOR1 partially complemented the cold sensitivity of Escherichia coli BX04 mutant lacking four cold shock proteins, indicating that OsDOR1 possessed RNA chaperone activity.