Amino acid and protein metabolism are interrelated and both play important roles in plant adaptation to heat stress. The objective of this study was to identify amino acids and soluble proteins associated with genetic variation in heat tolerance of hard fescue (Festuca trachyphylla). According to a previous screening experiment, the hard fescue cultivars Reliant IV and Predator were selected as heat-tolerant and heat-sensitive cultivars, respectively. Plants of these two hard fescue cultivars were exposed to heat stress at 38/33 °C (day/night) or optimal temperature at 21/18 °C in growth chambers. Each cultivar had four replications under each temperature, and the experimental design was a split-plot design, temperature as the main plots and cultivars as the subplots. Under heat stress, ‘Reliant IV’ exhibited higher turf quality (TQ) and greater membrane stability than ‘Predator’. In response to heat stress, total amino acid content increased, whereas total soluble protein content decreased in both cultivars. The greater accumulation of amino acids in ‘Reliant IV’ was contributed by the greater increase of proteins involved in the glycolysis and the tricarboxylic acid (TCA) cycle that provided carbon skeleton for amino acid synthesis. ‘Reliant IV’ leaves exhibited greater extent of increases in the content of six individual amino acids (histidine, glutamine, proline, threonine, aspartate, and tryptophan) than ‘Predator’ under heat stress. Several soluble proteins were upregulated in response to heat stress, to a greater extent in ‘Reliant IV’ than ‘Predator’, including the proteins involved in photosynthesis, protein folding, redox hemostasis, stress signaling, stress defense, cell organization, and metabolism. These differentially accumulated free amino acids and soluble proteins could be associated with the genetic variation in heat tolerance of hard fescue.
We wish to acknowledge the funding support by the National Institute of Food and Agriculture, U.S. Department of Agriculture, Specialty Crops Research Initiative, under award number 2012-51181-19932. We also thank Stephanie Rossi and Cathryn Chapman for critical review of the manuscript.
BaniwalS.K.BhartiK.ChanK.Y.FauthM.GanguliA.KotakS.MishraS.K.NoverL.PortM.ScharfK-D.TrippJ.2004Heat stress response in plants: A complex game with chaperones and more than twenty heat stress transcription factorsJ. Biosci.29471487
des Francs-SmallC.C.Ambard-BrettevilleF.SmallI.D.RémyR.1993Identification of a major soluble protein in mitochondria from nonphotosynthetic tissues as NAD-dependent formate dehydrogenasePlant Physiol.10211711177
FujitaM.FujitaY.NoutoshiY.TakahashiF.NarusakaY.Yamaguchi-ShinozakiK.ShinozakiK.2006Crosstalk between abiotic and biotic stress responses: A current view from the points of convergence in the stress signaling networksCurr. Opin. Plant Biol.9436442
KangJ.MehtaS.TuranoF.J.2004The putative glutamate receptor 1.1 (AtGLR1. 1) in Arabidopsis thaliana regulates abscisic acid biosynthesis and signaling to control development and water lossPlant Cell Physiol.4513801389
KhanJ.K.KuoY-H.KebedeN.LambeinF.1994Determination of non-protein amino acids and toxins in Lathyrus by high-performance liquid chromatography with precolumn phenyl isothiocyanate derivatizationJ. Chromatography687113119
MolloyM.P.HerbertB.R.WalshB.J.TylerM.I.TrainiM.SanchezJ.C.HochstrasserD.F.WilliamsK.L.GooleyA.A.1998Extraction of membrane proteins by differential solubilization for separation using two-dimensional gel electrophoresisElectrophoresis19837844
RochaM.LicausiF.AraujoW.L.Nunes-NesiA.SodekL.FernieA.R.van DongenJ.T.2010Glycolysis and the tricarboxylic acid cycle are linked by alanine aminotransferase during hypoxia induced by waterlogging of Lotus japonicusPlant Physiol.15215011513
VashishtA.A.PradhanA.TutejaR.TutejaN.2005Cold and salinity stress induced bipolar pea DNA helicase 47 is involved in protein synthesis and stimulated by phosphorylation with protein kinase CPlant J.447687
VeingerL.DiamantS.BuchnerJ.GoloubinoffP.1998The small heat-shock protein IbpB from Escherichia coli stabilizes stress-denatured proteins for subsequent refolding by a multichaperone networkJ. Biol. Chem.2731103211037
WangJ.JulianiH.R.JespersenD.HuangB.2017bDifferential profiles of membrane proteins, fatty acids, and sterols associated with genetic variations in heat tolerance for a perennial grass species, hard fescue (Festuca trachyphylla)Environ. Expt. Bot.1406575
YamakawaH.HakataM.2010Atlas of rice grain filling-related metabolism under high temperature: Joint analysis of metabolome and transcriptome demonstrated inhibition of starch accumulation and induction of amino acid accumulationPlant Cell Physiol.51795809