Cloning And Expression Analysis Of The ScALDH Gene Of Saccharum Spontaneum L.

Sugarcane is the most important sugar crops in China, an important energy crop as well, grown in tropical and subtropical regions.Sugarcane growth requires certain environmental conditions, especially for water and temperature.The drought has an effect on root growth rate, sugar accumulation, photosynthetic rate, physiological changes and so on.However the above 85% sugarcane was under no irrigation condition that the production of sugarcane is affected.Saccharum spontaneum L is a wild species of sugarcane with good resistance that make it the important parents of distant hybridization in sugarcane breeding.The traditional breeding method of sugarcane used is sexual hybridization, but with the development of molecular biology, scientists have begun to apply transgenic technology in sugarcane breeding.First, to find and clone the genes related to stress resistance, and then use the transgenic technology to import sugarcane receptor cells in that make them express.Use this method to increase the stress resistance and the yield of sugarcane.The present study was conducted to clone a drought resistant related gene from Saccharum spontaneum L,and detected the gene expression level under different drought conditions, and lay the foundation for drought resistance breeding. The ALDH gene was cloned with RT-PCR, and the nucleotide and amino acid sequences were analyzed as well.Use Blastx,Conserved Domain Search,ORF finder and MEGA,to compare the amino acids among different species;to find reading frames in the sequence;to Search Conserved Domain;to make evolutionary tree and so on. Real time-PCR was used to analyze the gene expression level of the cloned gene in drought stress.The total length of the ALDH gene fragment cloned were 1996 bp,including 1524 bp coding sequence,which was encoded 508 amino acids.The cloned sequence has a very high homology with other species’ amino acid sequence and have the conserved sequences of ALDH family; a complete open reading frame as well.Phylogenetic tree analysis showed that the relationship was most similar with corn.The real time-PCR data showed that The expression of the gene was expressed in a continuous accumulation mode.On the whole, the gene is respond to drought stress.The cloned gene belongs to the ALDH protein family, which has its typical function domain.The expression pattern analysis showed that the gene was involved in the process of drought stress.The results of this study were aimed at developing the excellent resources of wild species, as well as to explore the drought resistance of these resources, so as to provide the basis for the selection of the parents of the fine and drought resistance in the future.