Phytochrome Regulation of Carotenoid Biosynthesis during Ripening of Tomato Fruit

The accumulation of carotenoids such as lycopene and beta-carotene greatly influences the quality of ripe tomato (Lycopersicon esculentum) fruit because cellular levels of these compounds determine the intensity of red color. As well, lycopene has anti-cancer properties and beta-carotene is a Vitamin A precursor. Recent work has demonstrated phytochrome regulation of the carotenoid pathway but the mechanism is not completely understood. This work investigates phytochrome regulation of 1-deoxy-D-xylulose 5-phosphate synthase (DXS) and phytoene synthase (PSY), two key enzymes of carotenogenesis. A simple procedure for the assay of PSY from crude pericarp extracts was developed and mRNA levels of DXS and PSY1 genes were measured by relative RT-PCR. Discs from mature green tomatoes were ripened in total darkness, or in darkness interrupted by brief daily treatments of red light, or red light followed by far red light. After ten days of incubation, lycopene levels of red light-treated discs had reached ≈12 mg/100 g fresh weight; nearly a 50% increase over discs ripened in total darkness. This increase was not observed in discs treated with red light followed by far red light, demonstrating the red/far red reversibility (and thus phytochrome control) of carotenoid accumulation. Similar patterns of phytochrome control are observed for PSY activity but not for DXS and PSY1 transcript levels, suggesting the mechanism of control may be at the level of post-translational modification of PSY. Potential applications of this regulation of carotenoid accumulation will be discussed.

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Ubiquitination of phytoene synthase 1 precursor modulates carotenoid biosynthesis in tomato

Communications Biology ◽

10.1038/s42003-020-01474-3 ◽

2020 ◽

Vol 3 (1) ◽

Author(s):

Peiwen Wang ◽

Yuying Wang ◽

Weihao Wang ◽

Tong Chen ◽

Shiping Tian ◽

...

Keyword(s):

Global Analysis ◽

Tomato Fruit ◽

State Level ◽

Carotenoid Biosynthesis ◽

Phytoene Synthase ◽

Post Translational Modification ◽

Horticultural Crops ◽

Ring E3 Ligase ◽

Protein Ubiquitination ◽

Plastid Protein

AbstractCarotenoids are natural pigments that are indispensable to plants and humans, whereas the regulation of carotenoid biosynthesis by post-translational modification remains elusive. Here, we show that a tomato E3 ubiquitin ligase, Plastid Protein Sensing RING E3 ligase 1 (PPSR1), is responsible for the regulation of carotenoid biosynthesis. PPSR1 exhibits self-ubiquitination activity and loss of PPSR1 function leads to an increase in carotenoids in tomato fruit. PPSR1 affects the abundance of 288 proteins, including phytoene synthase 1 (PSY1), the key rate-limiting enzyme in the carotenoid biosynthetic pathway. PSY1 contains two ubiquitinated lysine residues (Lys380 and Lys406) as revealed by the global analysis and characterization of protein ubiquitination. We provide evidence that PPSR1 interacts with PSY1 precursor protein and mediates its degradation via ubiquitination, thereby affecting the steady-state level of PSY1 protein. Our findings not only uncover a regulatory mechanism for controlling carotenoid biosynthesis, but also provide a strategy for developing carotenoid-enriched horticultural crops.

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Carotenoid Production by Dunaliella salina under Red Light

Antioxidants ◽

10.3390/antiox8050123 ◽

2019 ◽

Vol 8 (5) ◽

pp. 123 ◽

Cited By ~ 10

Author(s):

Yanan Xu ◽

Patricia J. Harvey

Keyword(s):

Blue Light ◽

White Light ◽

High Intensity ◽

Dunaliella Salina ◽

Red Light ◽

Carotenoid Biosynthesis ◽

High Rate ◽

Carotenoid Content ◽

Photon Flux ◽

Carotenoid Accumulation

The halotolerant photoautotrophic marine microalga Dunaliella salina is one of the richest sources of natural carotenoids. Here we investigated the effects of high intensity blue, red and white light from light emitting diodes (LED) on the production of carotenoids by strains of D. salina under nutrient sufficiency and strict temperature control favouring growth. Growth in high intensity red light was associated with carotenoid accumulation and a high rate of oxygen uptake. On transfer to blue light, a massive drop in carotenoid content was recorded along with very high rates of photo-oxidation. In high intensity blue light, growth was maintained at the same rate as in red or white light, but without carotenoid accumulation; transfer to red light stimulated a small increase in carotenoid content. The data support chlorophyll absorption of red light photons to reduce plastoquinone in photosystem II, coupled to phytoene desaturation by plastoquinol:oxygen oxidoreductase, with oxygen as electron acceptor. Partitioning of electrons between photosynthesis and carotenoid biosynthesis would depend on both red photon flux intensity and phytoene synthase upregulation by the red light photoreceptor, phytochrome. Red light control of carotenoid biosynthesis and accumulation reduces the rate of formation of reactive oxygen species (ROS) as well as increases the pool size of anti-oxidant.

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Solar UV−B Radiation Influences Carotenoid Accumulation of Tomato Fruit through Both Ethylene-Dependent and -Independent Mechanisms

Journal of Agricultural and Food Chemistry ◽

10.1021/jf902555x ◽

2009 ◽

Vol 57 (22) ◽

pp. 10979-10989 ◽

Cited By ~ 45

Author(s):

Elisa Becatti ◽

Katia Petroni ◽

Deborah Giuntini ◽

Antonella Castagna ◽

Valentina Calvenzani ◽

...

Keyword(s):

Tomato Fruit ◽

Carotenoid Accumulation ◽

Solar Uv

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Morphology Evolution and Luminescence Properties of YF3: Sm Nano-/Microcrystals

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.463-464.112 ◽

2012 ◽

Vol 463-464 ◽

pp. 112-118

Author(s):

Feng Tao ◽

Geng Zhu ◽

Zhi Jun Wang ◽

Feng Pan ◽

Yu Feng Sun ◽

...

Keyword(s):

Hydrothermal Method ◽

Growth Mechanism ◽

Room Temperature ◽

Red Light ◽

Environmentally Friendly ◽

Morphology Evolution ◽

Flat Panel Display ◽

Flat Panel ◽

Display Devices ◽

Potential Applications

Abstract. Recently, there has been increasting interest in the doping of nano-/microcrystal hosts with Sm3+. However, very few examples of Sm3+doped YF3-based nanophosphors have been reported. In this paper, a variety of uniform YF3:Sm nano-/microcrystals have been successfully prepared by a facile, effective, and environmentally friendly hydrothermal method. The morphology evolution process has been investigated by quenching the reaction at different time. Based on the results, a possible growth mechanism is presented in detail. The as-obtained YF3:Sm nano-/microcrystals show strong yellow and red light emissions under room temperature, which is quite different from those reported previously and might find potential applications in fields such as light phosphor powers and advanced flat panel display devices.

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Manipulation of Environmental Stress Towards Lutein Production in Chlorella fusca Cell Culture

Journal of Pharmacy and Nutrition Sciences ◽

10.29169/1927-5951.2019.09.05.3 ◽

2019 ◽

Vol 9 (5) ◽

pp. 251-257

Author(s):

Rashidi Othman ◽

Norazian Mohd. Hassan ◽

Ainaa Eliah Abu Bakar ◽

Nur Hidayah Noh ◽

Nurrulhidayah Ahmad Fadzillah ◽

...

Keyword(s):

Cell Culture ◽

Drought Stress ◽

Environmental Stress ◽

Environmental Variables ◽

Metabolic Flux ◽

Experimental System ◽

Carotenoid Biosynthesis ◽

Chlorella Fusca ◽

Carotenoid Accumulation ◽

Media Formulation

All carotenoids originate from a single, common precursor, phytoene. The colour of carotenoids is determinedby desaturation, isomerization, cyclization, hydroxylation and epoxidation of the 40-carbon phytoene. The conjugated double-bond structure and nature of end ring groups confer on the carotenoids properties such as colour and antioxidant activity. Algae may become major sources of carotenoids but the extent of environmental stress and genetic influences on algae carotenoid biosynthesis are poorly understood. Carotenoid biosynthesis can be influenced by many aspects and is liable to geometric isomerization with the existence of oxygen, light and heat which affect the colour degradation and oxidation. Therefore, in this study carotenoid biogenesis is investigated in cell culture of Chlorella fusca as a potential model system for rapid initiation, and extraction of carotenoids by providing stringent control of genetic, developmental and environmental factors. The value of this experimental system for investigating key factors controlling the carotenoid accumulation is then tested by assessing the effects of environmental variables, such as drought stress, light intensity, nutrient strength and media formulation on carotenoid accumulation. Our findings revealed that the conversion of violaxanthin to lutein is due to irradiance stress condition, nutrient strength as well as drought stress. As a result, manipulation of environmental variables will up-regulate lutein concentration. This reaction will restrict the supply of precursors for ABA biosynthesis and the algae cell culture responds by increasing carotenogenic metabolic flux to compensate for this restriction. In conclusion, selecting the appropriate algae species for the appropriate environmental conditions is not only important for yield production, but also for nutritional value quality of carotenoid.

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Microscopic Analyses of Fruit Cell Plastid Development in Loquat (Eriobotrya japonica) during Fruit Ripening

Molecules ◽

10.3390/molecules24030448 ◽

2019 ◽

Vol 24 (3) ◽

pp. 448 ◽

Cited By ~ 2

Author(s):

Pengjun Lu ◽

Ruqian Wang ◽

Changqing Zhu ◽

Xiumin Fu ◽

Shasha Wang ◽

...

Keyword(s):

Fruit Ripening ◽

De Novo ◽

Microscopic Analysis ◽

Carotenoid Biosynthesis ◽

Direct Conversion ◽

Eriobotrya Japonica ◽

Plastid Development ◽

Carotenoid Accumulation ◽

The Relationship ◽

Late Stages

Plastids are sites for carotenoid biosynthesis and accumulation, but detailed information on fruit plastid development and its relation to carotenoid accumulation remains largely unclear. Here, using Baisha (BS; white-fleshed) and Luoyangqing (LYQ; red-fleshed) loquat (Eriobotrya japonica), a detailed microscopic analysis of plastid development during fruit ripening was carried out. In peel cells, chloroplasts turned into smaller chromoplasts in both cultivars, and the quantity of plastids in LYQ increased by one-half during fruit ripening. The average number of chromoplasts per peel cell in fully ripe fruit was similar between the two cultivars, but LYQ peel cell plastids were 20% larger and had a higher colour density, associated with the presence of larger plastoglobules. In flesh cells, chromoplasts could be observed only in LYQ during the middle and late stages of ripening, and the quantity on a per-cell basis was higher than that in peel cells, but the size of chromoplasts was smaller. It was concluded that chromoplasts are derived from the direct conversion of chloroplasts to chromoplasts in the peel, and from de novo differentiation of proplastids into chromoplasts in flesh. The relationship between plastid development and carotenoid accumulation is discussed.

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