Genes and Enzymes for Carotenoid Biosynthesis

Bartley, Glenn E.; Coomber, Shirley A.; Bartholomew, Dolores M.; Scolnik, Pablo A.

doi:10.1016/b978-0-12-715010-9.50016-5

Cited by 5 publications

(6 citation statements)

References 38 publications

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“…41 In tomato, these enzymes are regulated by light intensity in tissues as the plant changes from a vegetative to a fruiting state. 42 Carotenoid metabolism can be affected by factors external to the plant, and levels tend to increase in plants in response to stress, especially that due to drought, less than optimum temperature, and exposure to long periods of illumination.…”

Section: Discussionmentioning

confidence: 99%

Carotenoids in pungent and non‐pungent peppers at various developmental stages grown in the field and glasshouse

Russo

Howard

2002

J Sci Food Agric

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Carotenoids in edible portions of plants can provide health bene®ts to humans. How growing conditions affect levels of carotenoids in pepper fruits as they mature is not well known. Five cvs of bell pepper (Bell Captain, Melody, North Star, Ranger, Red Beauty) and ®ve cvs of pungent-type peppers (Anaheim, Ancho, Cayenne, Pimento, Red Cherry) were grown in a glasshouse and in the ®eld. Fruits were harvested at the green, turning (50% green) and mature red stages and analysed for levels of the carotenoids b-cryptoxanthin, a-carotene, b-carotene, capsanthin, lutein and zeaxanthin and totals of these carotenoids. Levels of provitamin A: retinol equivalents (RE) were derived from levels of b-cryptoxanthin, a-carotene and b-carotene. Levels of most carotenoids and RE were signi®cantly higher in glasshouse-grown plants, and most were higher in fruits at the red stage. Fruits of Ancho type had the most b-cryptoxanthin, a-carotene, b-carotene, total carotenoids and RE, while fruits of Red Cherry type had the most capsanthin and zeaxanthin, and fruits of Bell Captain had the most lutein. Interactions of the main effects variables, ie location of production (®eld vs glasshouse), stage of development and cultivar, indicated differences in patterns of carotenoid levels and RE. The data indicated that growing conditions in¯uenced carotenoid levels. The more consistent and protected conditions in the glasshouse may have caused carotenoid levels to be increased, especially at the red stage.

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Section: Discussionmentioning

confidence: 99%

Carotenoids in pungent and non‐pungent peppers at various developmental stages grown in the field and glasshouse

Russo

Howard

2002

J Sci Food Agric

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“…Phytoene is a colorless compound, t;-carotene is pale yellow, and later compounds are red (lycopene), orange (0-carotene), or yellow (xanthophylls or hydroxylated carotenoids). A byproduct of the pathway is the phytohormone abscisic acid, which modulates plant responses to various developmental and stress signals (Bartley et al, 1991a).…”

Section: Introductionmentioning

confidence: 99%

“…Plant genes for enzymes of the carotenoid biosynthesis pathway are nuclear, and the protein products are imported into organelles (reviewed in Bartley et al, 1991a). Molecular probes for carotenoid biosynthesis genes are now becoming available.…”

Section: Introductionmentioning

confidence: 99%

Regulation of Carotenoid Biosynthesis during Tomato Development

Giuliano¹,

Bartley²,

Scolnik³

1993

The Plant Cell

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Phytoene synthase (Psy) and phytoene desaturase (Pds) are the first dedicated enzymes of the plant carotenoid biosynthesis pathway. We report here the organ-specific and temporal expression of PDS and PSY in tomato plants. Light increases the carotenoid content of seedlings but has little effect on PDS and PSY expression. Expression of both genes is induced in seedlings of the phytoene-accumulating mutant ghost and in wild-type seedlings treated with the Pds inhibitor norflurazon. Roots, which contain the lowest levels of carotenoids in the plant, have also the lowest levels of PDS and PSY expression. In flowers, expression of both genes and carotenoid content are higher in petals and anthers than in sepals and carpels. During flower development, expression of both PDS and PSY increases more than 10-fold immediately before anthesis. During fruit development, PSY expression increases more than 20-fold, but PDS expression increases less than threefold. We concluded that PSY and PDS are differentially regulated by stress and developmental mechanisms that control carotenoid biosynthesis in leaves, flowers, and fruits. We also report that PDS maps to chromosome 3, and thus it does not correspond to the GHOST locus, which maps to chromosome 11.

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“…In all microbial carotenoid desaturases analyzed, the dinucleotide binding fold is located near the N terminus (5,24). This plus the facts that these proteins are encoded by nuclear genes and are targeted to plastid envelopes (2,32) suggest that the soybean Pdsl protein is initially synthesized as a higher molecular weight precursor, possessing a transit peptide that targets the protein to plastids. To test this we conducted in vitro chloroplast import experiments.…”

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confidence: 99%

“…Absorption of visible light and photoprotection are mediated by a chain of conjugated double bonds, the chromophore, that is formed by successive desaturations of the colorless precursor phytoene (1,2). Deduced peptide sequences of several microbial carotenoid desaturases have been reported (3)(4)(5)(6).…”

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confidence: 99%