Transcription profiling of wheat variety Chinese Spring and two derived chromosome 5A substitution lines treated with cold stress

ABSTRACT: Chromosome 5A of wheat is a major regulator of freezing tolerance. It harbours gene loci controlling freezing tolerance (Fr-A1 and Fr-A2) and vernalization requirement (Vrn-A1). The number of cold-responsive genes and their functional classification was studied by cDNA macroarray-based transcript profiling in the moderately freezing-sensitive wheat (Triticum aestivum L.) variety Chinese Spring and two derived chromosome 5A substitution lines exhibiting lower or higher levels of freezing tolerance, respectively. During 21-days of cold acclimation at 2 °C the transcript level changed significantly for 681 (6.6%) out of 10,297 studied unigenes. The freezing-tolerant substitution line exhibited about 1.5-fold higher number of differentially expressed genes compared to the sensitive one. Transcript levels of several genes were altered by cold treatment only in one of the three genotypes. For 78 genes regulation by factors hosted on chromosome 5A was determined and postulated. These genes encoded proteins involved in transcriptional regulation, defence processes and carbohydrate metabolism. Three of the chromosome 5A-affected genes, having especially strong and rapid cold-induced changes of transcript level, namely Tacr7 (Triticum aesticum cold-responsive gene 7 homolog), Cab (Ca2+-binding), and Dem (deficient embryo and meristems) were genetically mapped and characterized in further detail. Only the gene Cab was located on chromosome 5A, whereas Tacr7 and Dem resided on other chromosomes. Although chromosome 5A-affected genes are also found to be localised on the same chromosome, the present findings indicate that chromosome 5A is strongly involved in trans-regulation of genes potentially due to the presence of regulatory loci, like Fr-A2, which is harboring numerous CBF transcription factors.

ORGANISM(S): Triticum aestivum

SUBMITTER: Gabor Kocsy 

PROVIDER: E-IPKG-10 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress