Cloning,Characterization and Expression of a csAtPR5-Like Gene in Wheat

Wheat(Triticum aestivum L.) line 'Lankao 90(6)' carried a recessive powdery mildew resis-tance gene which was temporarily named PmLK906 and located on chromosome 2AL.Wheat gene chip hybridization was made by using powdery mildew resistant and susceptible cDNA bulks as probes assembled with homozygous F3 lines derived from a cross of 'Chinese Spring'/'Lankao 90(6)21-12'.The results indicated that a gene similar to csAtPR5 of Aegilops tauschii was expressed about 24.2 times higher in the resistant bulk than in the susceptible bulk.Subsequently,a new 2 125 bp full-length cDNA clone similar to csAtPR5,temporarily named TaAetPR5(GenBank accession number: EU082094),was isolated from 'Lankao 90(6)21-12'.The cDNA sequences of TaAetPR5 and csAtPR5 shared 93% identity.TaAetPR5 encoded a peptide consisted of 657 amino acids,and was 88% identity to that of csAtPR5.Prediction analysis showed protein TaAetPR5 was 74.5 kDa,and that its pI was 6.82.TaAetPR5 was probably a soluble globular protein and was in nucleus with 95% possibility.The transcribing of TaAetPR5 in 'Lankao 90(6)21-12' was enhanced from 12 to 72 hours after inoculation with Blumeria graminis f.sp.tritici.TaAetPR5 couldn't be detected in powdery mildew susceptible cultivar 'Chinese Spring'.