title: Combining gene expression and genetic analyses to identify candidate genes involved in cold responses in pea.
abstract: Cold stress affects plant growth and development. In order to better understand the responses to cold (chilling or freezing tolerance), we used two contrasted pea lines. Following a chilling period, the Champagne line becomes tolerant to frost whereas the Terese line remains sensitive. Four suppression subtractive hybridisation libraries were obtained using mRNAs isolated from pea genotypes Champagne and Terese. Using quantitative polymerase chain reaction (qPCR) performed on 159 genes, 43 and 54 genes were identified as differentially expressed at the initial time point and during the time course study, respectively. Molecular markers were developed from the differentially expressed genes and were genotyped on a population of 164 RILs derived from a cross between Champagne and Terese. We identified 5 candidate genes colocalizing with 3 different frost damage quantitative trait loci (QTL) intervals and a protein quantity locus (PQL) rich region previously reported. This investigation revealed the role of constitutive differences between both genotypes in the cold responses, in particular with genes related to glycine degradation pathway that could confer to Champagne a better frost tolerance. We showed that freezing tolerance involves a decrease of expression of genes related to photosynthesis and the expression of a gene involved in the production of cysteine and methionine that could act as cryoprotectant molecules. Although it remains to be confirmed, this study could also reveal the involvement of the jasmonate pathway in the cold responses, since we observed that two genes related to this pathway were mapped in a frost damage QTL interval and in a PQL rich region interval, respectively.
authors: Université Lille 1, UMR SADV 1281, Stress Abiotiques et Différenciation des Végétaux cultivés, Université Lille Nord de France, Lille 1, SN2, F-59650 Villeneuve d'Ascq, France. Sylvain.legrand@univ-lille1.fr
authors: Sylvain
authors: S
authors: Legrand
authors: Gilles
authors: G
authors: Marque
authors: Christelle
authors: C
authors: Blassiau
authors: Aurélie
authors: A
authors: Bluteau
authors: Anne-Sophie
authors: AS
authors: Canoy
authors: Véronique
authors: V
authors: Fontaine
authors: Odile
authors: O
authors: Jaminon
authors: Nasser
authors: N
authors: Bahrman
authors: Julie
authors: J
authors: Mautord
authors: Julie
authors: J
authors: Morin
authors: Aurélie
authors: A
authors: Petit
authors: Alain
authors: A
authors: Baranger
authors: Nathalie
authors: N
authors: Rivière
authors: Jeroen
authors: J
authors: Wilmer
authors: Bruno
authors: B
authors: Delbreil
authors: Isabelle
authors: I
authors: Lejeune-Hénaut
mesh_terms: D058639:Cold-Shock Response; D020224:Expressed Sequence Tags / Q000737:chemistry / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D015723:Gene Library; D017343:Genes, Plant; D005838:Genotype; D008969:Molecular Sequence Data; D018532:Pisum sativum / Q000737:chemistry / Q000235:genetics / Q000502:physiology*; D016133:Polymerase Chain Reaction; D040641:Quantitative Trait Loci; D017422:Sequence Analysis, DNA
keywords: C-LT; C-N; Champagne plants under low-temperature treatment; Chilling; Cold acclimation; FD; FT; Freezing tolerance; HRM; LG; LT; N; PQL; Pisum sativum; SSCP; SSH; Suppression subtractive hybridisation; T-LT; T-N; Terese plants under low-temperature treatment; WFD; control/unchilled; control/unchilled Champagne plants; control·unchilled Terese plants; freezing tolerance; frost damages in controlled conditions; high resolution melting curve; linkage group; low temperature; protein quantitative locus; single strand conformation polymorphism; suppression subtractive hybridisation; winter frost damages in the field