Comparative analysis of metabolic proteome variation in ascorbate-primed and unprimed wheat seeds during germination under salt stress
No Thumbnail Available
Date
2014-05-21
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
elsevier
Abstract
Seed priming with ascorbic acid improves salt tolerance in durum wheat. For
understanding the potential mechanisms underlying this priming effect a gel-free shotgun
proteomic analysis was performed comparing unprimed to ascorbate-primed wheat seed
during germination under saline and non-saline conditions. Since seed germination is the
result of interplay or cross-talk between embryo and embryo-surrounding tissues, we
studied the variation of metabolic proteome in both tissues separately. 167 of 697 identified
and 69 of 471 identified proteins increase or decrease in abundance significantly in
response to priming and/or salinity compared to untreated, unstressed control in embryo
and embryo-surrounding tissues, respectively. In untreated wheat embryo salt stress was
accompanied by change in 129 proteins, most of which are belonging to metabolism,
energy, disease/defense, protein destination and storage categories. Ascorbate pretreatment
prevents and counteracts the effects of salinity upon most of these proteins and
changes specifically the abundance of 35 others proteins, most of which are involved in
metabolism, protein destination and storage categories. Hierarchical clustering analysis
revealed three and two major clusters of protein expression in embryo and embryosurrounding
tissues, respectively. This study opens promising new avenues to understand
priming-induced salt tolerance in plants.
Biological significance
To clearly understand how ascorbate-priming enhance the salt tolerance of durum wheat
during germination, we performed for the first time a comparative shotgun proteomic
analysis between unprimed and ascorbate-primed wheat seeds during germination under
saline and non-saline conditions. Furthermore, since seed germination is the result of