Wheat glutenin subunits and dough elasticity: findings of the EUROWHEAT project

Detailed studies of wheat glutenin subunits have provided novel details of their molecular structures and interactions which allow the development of a model to explain their role in determining the visco-elastic properties of gluten and dough. The construction and analysis of near-isogenic and transgenic lines expressing novel subunit combinations or increased amounts of specific subunits allows differences in gluten properties to be related to the structures and properties of individual subunits, with potential benefits for the production of cultivars with improved properties for food processing or novel end user

Dynamic trafficking of wheat γ-gliadin and of its structural domains in tobacco cells, studied with fluorescent protein fusions

Prolamins, the main storage proteins of wheat seeds, are synthesized and retained in the endoplasmic reticulum (ER) of the endosperm cells, where they accumulate in protein bodies (PBs) and are then exported to the storage vacuole. The mechanisms leading to these events are unresolved. To investigate this unconventional trafficking pathway, wheat γ-gliadin and its isolated repeated N-terminal and cysteine-rich C-terminal domains were fused to fluorescent proteins and expressed in tobacco leaf epidermal cells. The results indicated that γ-gliadin and both isolated domains were able to be retained and accumulated as protein body-like structures (PBLS) in the ER, suggesting that tandem repeats are not the only sequence involved in γ-gliadin ER retention and PBLS formation. The high actin-dependent mobility of γ-gliadin PBLS is also reported, and it is demonstrated that most of them do not co-localize with Golgi body or pre-vacuolar compartment markers. Both γ-gliadin domains are found in the same PBLS when co-expressed, which is most probably due to their ability to interact with each other, as indicated by the yeast two-hybrid and FRET-FLIM experiments. Moreover, when stably expressed in BY-2 cells, green fluorescent protein (GFP) fusions to γ-gliadin and its isolated domains were retained in the ER for several days before being exported to the vacuole in a Golgi-dependent manner, and degraded, leading to the release of the GFP ‘core’. Taken together, the results show that tobacco cells are a convenient model to study the atypical wheat prolamin trafficking with fluorescent protein fusions

Différences d'hydrophobicité de surface des gliadines de deux variétés de blé dur de bonne et de mauvaise qualité

International audienc

High performance of Bacillus subtilis lipopeptides having myristic and pentadecanoic alkyl chains in foaming capacity and stability

BIOTEC

Nouvelle methode d'analyse des proprietes moussantes des ingredients alimentaires

National audienc

Desamidation acide et modification enzymatique a pH 10 de gliadines de ble : influence sur leurs proprietes fonctionnelles

24 ref. * communication oraleInternational audienc