Oil body proteins sequentially accumulate throughout seed development in Brassica napus.

Despite the importance of seed oil bodies (OBs) as enclosed compartments for oil storage, little is known about lipid and protein accumulation in OBs during seed formation. OBs from rapeseed (Brassica napus) consist of a triacylglycerol (TAG) core surrounded by a phospholipid monolayer embedded with integral proteins which confer high stability to OBs in the mature dry seed. In the present study, we investigated lipid and protein accumulation patterns throughout seed development (from 5 to 65 days after pollination [DAP]) both in the whole seed and in purified OBs. Deposition of the major proteins (oleosins, caleosins and steroleosins) into OBs was assessed through (i) gene expression pattern, (ii) proteomics analysis, and (iii) protein immunodetection. For the first time, a sequential deposition of integral OB proteins was established. Accumulation of oleosins and caleosins was observed starting from early stages of seed development (12-17 DAP), while steroleosins accumulated later (~25 DAP) onwards.

Genetic map construction and quantitative trait loci (QTL) mapping for nitrogen use efficiency and its relationship with productivity and quality of the biennial crop Belgian endive (Cichorium intybus L.).

A genetic study of the biennial crop Belgian endive (Cichorium intybus) was carried out to examine the effect of nitrogen nutrition during the vegetative phase in the control of the productivity and quality of the chicon (etiolated bud), a crop that grows during the second phase of development (forcing process). A population of 302 recombinant inbred lines (RIL) was obtained from the cross between contrasting lines "NS1" and "NR2". A genetic map was constructed and QTLs of several physiological and agronomical traits were mapped under two levels of nitrogen fertilization during the vegetative phase (N- and N+). The agronomical traits showed high broad sense heritability, whereas the physiological traits were characterized by low broad sense heritability. Nitrogen reserves mobilization during the forcing process was negatively correlated with nitrogen reserves content of the tuberized root and common QTLs were detected for these traits. The chicon productivity and quality were not correlated, but showed one common QTL. This study revealed that chicon productivity and quality were genetically associated with nitrogen reserves mobilization that exerts opposite effects on both traits. Chicon productivity was positively correlated with N reserves mobilization under N- and N+ and a common QTL with the same additive effects was detected for both traits. Chicon quality was negatively correlated with N reserves mobilization under N- and N+ and a common QTL with opposite additive effects was detected for both traits. These results lead to the conclusion that N reserves mobilization is a more effective trait than N reserves content in predicting chicon productivity and quality. Finally, this study revealed agronomical and physiological QTLs utilizable by breeders via marker-assisted selection to aid the optimization of chicon quality under adapted N fertilization.

Protein composition of oil bodies from mature Brassica napus seeds.

Seed oil bodies (OBs) are intracellular particles storing lipids as food or biofuel reserves in oleaginous plants. Since Brassica napus OBs could be easily contaminated with protein bodies and/or myrosin cells, they must be purified step by step using floatation technique in order to remove non-specifically trapped proteins. An exhaustive description of the protein composition of rapeseed OBs from two double-zero varieties was achieved by a combination of proteomic and genomic tools. Genomic analysis led to the identification of sequences coding for major seed oil body proteins, including 19 oleosins, 5 steroleosins and 9 caleosins. Most of these proteins were also identified through proteomic analysis and displayed a high level of sequence conservation with their Arabidopsis thaliana counterparts. Two rapeseed oleosin orthologs appeared acetylated on their N-terminal alanine residue and both caleosins and steroleosins displayed a low level of phosphorylation.

Daily polyphenol intake in France from fruit and vegetables.

The objective of this study was to create a French database on the polyphenol content of fruit and vegetables as uncooked fruits and vegetables and then to evaluate polyphenol intake through fruit and vegetable consumption in France. To achieve this, we used the Folin-Ciocalteu method adapted to fruit and vegetable polyphenol quantitation (1). Vegetables with the highest polyphenol concentration were artichokes, parsley, and brussels sprouts [>250 mg of gallic acid equivalent (GAE)/100 g fresh edible portion (FEP)]; fruits with the highest concentrations were strawberries, lychees, and grapes (>180 mg of GAE/100 g FEP). Conversely, melons (Cantaloupe cv.) and avocados had the lowest polyphenol concentration for fruits and vegetables, respectively. Based on fruit consumption data, apples and strawberries are the main sources of polyphenols in the French diet, whereas potatoes, lettuces, and onions are the most important vegetable sources. Total polyphenol intake from fruit is about 3 times higher than from vegetables, due to the lower polyphenol concentration in vegetables. The calculation of polyphenol intake, based on both assessment methods used [(Société d'Etudes de la Communication, Distribution et Publicité (SECODIP) and Supplémentation en Vitamines et Minéraux Antioxydants (SUVIMAX)], showed that apples and potatoes provide approximatively half of the total polyphenol intake from fruit and vegetables in the French diet.