8th INTERNATIONAL WHEAT CONFERENCE

quANTITATIVe ANALySIS of PRoTeome IN WheAT
SuBSTITuTIoN LINeS duRINg LoNg-TeRm CoLd
ACCLImATIoN
Vítámvás P. 1 , Kosová K. 1 , Škodáček Z. 1 , Pánková K. 1 ,
Milec Z. 1 , Planchon S. 2 , Renaut J. 2 , Prášil I.T. 1
1 Crop Research Institute, Prague, Czech Republic;
2 Centre de Recherche Public - Gabriel Lippmann, Luxembourg
E-mail: k.pankova@vurv.cz
After exposure of wheat plants to low non-freezing temperatures a higher level of frost
tolerance developed during the process called cold acclimation. The aim was to compare
the changes in proteome, between wheat substitution lines, for the homoeologous group 5
chromosomes which carry the genes regulating for frost tolerance. The quantitative changes
in crown proteome during the acclimation were evaluated by 2D-DIGE. Spots of interest,
containing 208 differentially expressed polypeptides (absolute abundance variation of
at least 1.5-fold, p>0.05), were selected, digested, and analyzed by MALDI-TOF/TOF. Using
PCA analysis, it was found out that the substitutions lines were grouped according to
the duration of cold acclimation. The major changes in the expression of proteins in coldtreated
plants in comparison with control ones were in the following processes: 1/ Carbohydrate
metabolism: An up-regulation of enzymes involved in glycolytic pathway such as
enolase, phosphoglycerate mutase and cytosolic 3-phosphoglycerate kinase was found. In
contrast, a decrease in enzymes involved in anabolic pathways such as sucrose synthase
1, UDP-glucosyltransferase BX8, UDP-glucose pyrophosphorylase and UTP-glucose-1phosphate
uridylyltransferase was detected. 2/ Cell redox homeostasis: An up-regulation
of enzymes which catalyse biosynthesis of active forms of glutathione and ascorbate was
detected. A decrease of ascorbate peroxidase and an increase of monodehydroascorbate
reductase leads to the elevation of ascorbate and reduction of monodehydroascorbate could
be proposed in cold-acclimated crown tissues. These changes indicate an enhanced reducing
activity in cold-acclimated tissues. 3/ Protein folding: An up-regulation of several chaperones,
especially HSP70, mitochondrial chaperonin 21, chloroplast precursor of RuBisCO
large subunit-binding protein, or copper-binding chopper chaperone was found. Generally,
it can be concluded that an increase in proteins with chaperone and generally protective
functions was found. 4/ Stress-related proteins: A significant increase in COR/LEA proteins
(dehydrin, WCOR615, salt-tolerant protein) was found. These proteins exhibit protective
functions against cellular dehydration during several stresses, especially drought and salt,
but also cold stress. 5/ One-carbon metabolism (methylation reactions): An up-regulation
of enzymes involved in methylation reactions (S-adenosyl-L-methionine synthase and Sadenosyl-L-homocystein
hydrolase) was found.
Keywords: Cold acclimation; frost tolerance; proteom; stress proteins; Triticum aestivum
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