Construction of Forward and Reverse Subtracted cDNA Libraries From Opisthopappus Taihangensis (Ling) C. Shih. Under Drought Stress

Opisthopappus taihangensis (Ling) C. Shih. grows vigorously in both arid and saline soils, which indicates its strong resistance to drought stress. To study the molecular mechanisms of drought-stress resistance and obtain differential expressed genes in O. taihangensis, suppression substractive hybridization (SSH) was employed in this study. Forward and reverse subtracted cDNA libraries were constructed with leaves treated by PEG solution. Results of electrophoresis suggested noticeable differences in PCR bands between subtracted sample and non-subtracted sample, which indicated that the substraction was effective. In the substracted cDNA library, the recombination rate was 92%, with the size of inserts between 200-600bp. Through sequencing the partial clones of forward subtracted cDNA libraries, a number of genes related to drought resistance were obtained and verified with Northern hybridization, such as bZIP transcription factor, MADS-box protein, SOD, calcium-dependent protein kinase genes etc. The results provided important information for cloning new genes from O. taihangensis and led to further study of molecular mechanism related to drought resistance. Dr. Qixiang Zhang is the corresponding author.