Isolation And Characterization Of TaGSK1 Involved In Salt-Tolerance In Wheat

Our pevious studies showed as follows : firstly, the fragment of TaGSK1gene was cloned and sequenced successfully .The amino acid sequence and the structures of the protein were analysed by using softwares for molecular biology. The cDNA sequence of TaGSKl from Triticum asetium L. was registered at GenBank as a new gene with the accession number of AF525086. In succession, using DNA recombinant technique, a recombinant protein expression vector-pBV221-gskl and pBI121-gskl of TaGSKl was constructed basing on the clone vector -pD-T23. After analysis and expression in E.coli DH5 a and BL21 of TaGSKl cDNA. a sepcial expression protein of molecular weight of 43.5KD can be produced and the quantity of expressed apart in them reach to 8% and 10.8%. Through analyzing the salt-tolerant character of the transformant, we found that the salt resistance of the transformant was higher than host bacterium.In order to distinguish the difference of TaGSKl between salt-stress resistant and salt-stress sensitive on the DNA level, we used the same primers amplyfy and clone the fragments of TaGSKl DNA from the genome of wheat lines RH8706-49 and H 8706-34. The sequence results indicated that TaGSKl gene has high conservation and the difference of it's salt resistance expressed mainly on the transcription and translation level however on the DNA level there is no any difference. It has three copies in the genome that was testified by Southern Blot. It was rare reported in our country that mature embryo-derived calli from Wheat as the materials were transformed with Agrobacterium tumefaciens . We studied the TaGSKl"s transformation of Wheat (Triticum asetium L.) respectively through two method : Agrobacterium tumefaciens -mediated transformation and particle bombardment using the same materials of mature embryo-derived calli from salt-stress sensitive Wheat lines and the binary plant vector pBI121-gskl.Transgenic callus of Wheat were produced ,using Kna and NaCl for selection.The callus were demonstrated positive when genomic DNA of transgenic callus was identified by the method of PCR,using two termination sequence of NPT-II gene as primers. Transgenic callus of Wheat can grow prosperous in 0.5% NaCl however the control lines almost all changed brown even died.Our pilot study indicated that TaGSKl gene can enhance the tolerance of salt-stress sensitive Wheat lines. In addition .our study showed, that the two transformation methods have excellence and shortcoming of themselves and the rates transformation is relative with the genotype closely.These results had important significance to research deeply the expression control and protien function of TaGSKl . to open out the mechanism of salt tolerance in Wheat and to exploit and use the transformation techniques of Wheat.