| China is the major cotton planting country which has drought stress heavily. The Conventional cotton breeding method is very difficult to conquer the trait because of lacking of special germplasms. In this study, it is the first time to use suppression subtractive hybridization to construct cotton (Gossypium arboreum L.) drought-related cDNA library. Comparing with the conventional cotton breeding, this method could isolate some genes associate with drought-tolerance in molecular level. It is convenient for the further research such as isolation, clone, and transformation in cotton.This study constructed high quality cotton (Gossypium arboreum L.) drought-related cDNA library by SSH successfully; it was checked and analyzed by Blue-White Bolting, Colony PCR, reverse-Northern blotting, Bioinformatics, RT-PCR. Finally, 392 positive clones were obtained by reverse-Northern which in the 960 Colony PCR clones. After cluster analysis of the ESTs sequences, 265 unigenes were obtained, including 41 contigs and 224 singlets. The Blastx results indicated that many drought stress-induced genes were found in this cDNA library which can be divided into two kinds: one is function protein cluster such as: photosynthesis enzymes, heat shock protein, ferritin, glycometabolism protein, protein enzyme, which induced by protective function in cells; the other is regulatory proteins cluster such as: transcription factor, protein kinase, which give signals transduction under drought stress or ralation between genes expression. Besides those, 46 unknown ESTs sequences were looked forward to the further research. This study is helpful for cloning the whole, useful drought-related genes in cotton by the cDNA library. Meanwhile, it brings some information for drought-tolerance mechanism, and founds a base for molecular breeding in cotton. |
