Effect of Aluminum Treatment on Proteomes of Radicles of Seeds Derived from Al-Treated Tomato Plants

Abstract

Aluminum (Al) toxicity is a major constraint to plant growth and crop yield in acid soils. Tomato cultivars are especially susceptible to excessive Al3+ accumulated in the root zone. In this study, tomato plants were grown in a hydroponic culture system supplemented with 50 µM AlK(SO4)2. Seeds harvested from Al-treated plants contained a significantly higher Al content than those grown in the control hydroponic solution. In this study, these Al-enriched tomato seeds (harvested from Al-treated tomato plants) were germinated in 50 µM AlK(SO4)2 solution in a homopiperazine-1,4-bis(2-ethanesulfonic acid) buffer (pH 4.0), and the control solution which contained the buffer only. Proteomes of radicles were analyzed quantitatively by mass spectrometry employing isobaric tags for relative and absolute quantitation (iTRAQ®). The proteins identified were assigned to molecular functional groups and cellular metabolic pathways using MapMan. Among the proteins whose abundance levels changed significantly were: a number of transcription factors; proteins regulating gene silencing and programmed cell death; proteins in primary and secondary signaling pathways, including phytohormone signaling and proteins for enhancing tolerance to abiotic and biotic stress. Among the metabolic pathways, enzymes in glycolysis and fermentation and sucrolytic pathways were repressed. Secondary metabolic pathways including the mevalonate pathway and lignin biosynthesis were induced. Biological reactions in mitochondria seem to be induced due to an increase in the abundance level of mitochondrial ribosomes and enzymes in the TCA cycle, electron transport chains and ATP synthesis.

Drought-Induced Leaf Proteome Changes in Switchgrass Seedlings

“…Activation time for HCD analysis was 0.1 min. All data were acquired using XCalibur 2.1 (Thermo-Fisher Scientific) [18,24]. Proteins were identified using the MS data to query the switchgrass annotated database () via Mascot v2.3.02 (Matrix Sciences, Boston, MA, USA).…”

Quantitative iTRAQ Proteomics Revealed Possible Roles for Antioxidant Proteins in Sorghum Aluminum Tolerance

“…The peptide separation was accomplished using an Acquity UPLC System and UV detection (Waters, Milford, MA) coupled with a robotic fraction collector (Probot; Dionex, Sunnyvale, CA, USA) as reported previously (Okekeobu et al, 2014). Specifically, the iTRAQ 8-plex tagged tryptic peptides were reconstituted in buffer A (20 mM ammonium formate pH 9.5 in water), and half of the sample was loaded onto an Acquity UPLC BEH C18 column (1.7 μm, 2.1 × 100 mm, Waters, Milford, MA) with 20 mM ammonium formate (NH4FA), pH 9.5 as buffer A and 90% ACN/10% 20 mM NH4FA as buffer B.…”

“…The Sorghum bicolor protein RefSeq sequence database containing 75,079 sequence entries was downloaded on 9 Dec, 2014 from NCBInr and used for database searches. The default search settings used for 8-plex iTRAQ quantitative processing and protein identification in Mascot server were as described previously (Yang Y. et al, 2011; Okekeobu et al, 2014). In brief, two miss-cleavage for full trypsin digestions were conducted with fixed methylthio modification of cysteine, fixed 8-plex iTRAQ modifications on lysine and N-terminal amines and variable modifications of methionine oxidation and deamidation on asparagines/glutamine residues.…”

Effects of Al3+ and La3+ Trivalent Metal Ions on Tomato Fruit Proteomes

“…Tomato is sensitive to Al toxicity [9,10,11] at both the vegetative and reproductive stages. Previous studies have shown that Al treatments induced global changes in proteome expression in roots, leaves, fruits and seeds in tomato [12,13,14]. These molecular responses are mobilized to deal with Al 3+ ion toxicity, as well as the Al-induced interferences in plant mineral nutrition [13,15].…”

“…Proteomics analysis has proven to be a very powerful tool in revealing the relative abundance of proteins or the identification of individual proteins related to specific cell functions in plants [24,25,26]. More importantly, our previous studies have shown that Al treatments affected proteome composition, not only in roots, but also in the aboveground tissues, including leaves, cotyledons, seeds and germinating radicles derived from the Al-treated seeds [12,25,26]. …”