The photoprotective role of the universal violaxanthin cycle that interconverts violaxanthin (V), antheraxanthin (A), and zeaxanthin (Z) is well established, but functions of the analogous conversions of lutein-5,6-epoxide (Lx) and lutein (L) in the selectively occurring Lx cycle are still unclear. We investigated carotenoid pools in Lx-rich leaves of avocado (Persea americana) during sun or sh...

Lutein, a dihydroxy derivative of -carotene ( , -carotene), is the most abundant carotenoid in photosynthetic plant tissues where it plays important roles in light-harvesting complex-II structure and function. The synthesis of lutein from lycopene requires at least four distinct enzymatic reactions: and -ring cyclizations and hydroxylation of each ring at the C-3 position. Three carotenoid hydr...

The yellow color of inner leaves in Chinese cabbage depends on its lutein and carotene content. To identify responsible genes for yellow pigmentation in leaves, the transcriptome profiles of white (Kenshin) and yellow leaves (Wheessen) were examined using the Br300K oligomeric chip in Chinese cabbage. In yellow leaves, genes involved in carotene synthesis (BrPSY, BrPDS, BrCRTISO, and BrLCYE), l...

Two F2carrot (Daucus carota L.) populations (orange rooted Brasilia x very dark orange rooted High CaroteneMass HCM cross and the dark orange rooted cultivated variety B493 x white rooted wild carrot Queen Anne’s Lace QAL cross) with very unrelated genetic backgrounds were used to investigate intrinsic factors limiting carotenoid accumulation in carrots by applying phenotypic correlation and pa...

Here, a comprehensive proteomic analysis of the chromoplasts purified from sweet orange using Nycodenz density gradient centrifugation is reported. A GeLC-MS/MS shotgun approach was used to identify the proteins of pooled chromoplast samples. A total of 493 proteins were identified from purified chromoplasts, of which 418 are putative plastid proteins based on in silico sequence homology and fu...

Carotenoids underlie many of the vibrant yellow, orange, and red colors in animals, and are involved in processes ranging from vision to protection from stresses. Most animals acquire carotenoids from their diets because de novo synthesis of carotenoids is primarily limited to plants and some bacteria and fungi. Recently, sequencing projects in aphids and adelgids, spider mites, and gall midges...

A dietary source of retinoid or carotenoid has been shown to be necessary for the biosynthesis of functional visual pigment in flies. In the present study, the larvae or adults of Drosophila melanogaster were administered specific carotenoid-containing diets and high performance liquid chromatography was used to identify and quantify the carotenoids in extracts of wild type and ninaD visual mut...

In an effort to understand the more general mechanisms and rates of pre-depositional reactions that transform organic matter, the types and relevant time scales of reactions that transform carotenoid pigments in the oceanic water column were studied. In the present study, a model was constructed for organic matter cycling that consisted of three parts: 1) the synthesis of carotenoid pigments by...

The 2-C-methyl-D-erythritol 4-phosphate (MEP) pathway leads to the synthesis of isopentenyl diphosphate in plastids. It is a major branch point providing precursors for the synthesis of carotenoids, tocopherols, plastoquinone and the phytyl chain of chlorophylls, as well as the hormones abscisic acid and gibberellins. Consequently, disruption of this pathway is harmful to plants. We developed a...

Combined use of association mapping and linkage analysis is highly effective in the identification of loci governing quantitatively inherited traits. In this strategy, the underlying genetic basis and function of QTL can be tested through a hypothesis driven approach that draws upon biochemical information from model species. Results from the linkage mapping experiment can then be reconsidered ...