Cloning, Expression And Molecular Evolution Of STS Gene In Vitis Vinifera

Stilbenes constitutes an important sort of phytoalexin functioning in the process of stress reaction and protection against environmental damage such as microorganic ones. Stilbene synthase(STS), belongs to type III polyketide synthase(PKSIII) superfamily and it’s the key enzyme of stilbenes biosynthesis. Its activity is directly regulated by the activity and expression of STS genes.In nature there are two types of stilbenes-resveratrol and pinosylvin. In this article, we adopt Vitis vinifera L. which has the higher content of resveratrol as the research material, the STS gene as the research object and isolate a member of VvSTS gene family VvSTS6 from leaves of Vitis vinifera L. with the method of reverse transcription-polymerase chain reaction.By retrieving NCBI-UniGene database, six VvSTS genes with complete open reading frame(ORF) are obtained. Then we search for STS amino acid sequences of other species that have higher similarity with VvSTS6 encoding amino acid sequences and their corresponding coding sequences(CDS), and make bioinformatics analysis of these gene sequences and amino acid sequences above, mainly including bioinformatics analysis of VvSTS genes and molecular evolution of STS genes of different species:The first part covers physical and chemical properties, structural characteristics and biochemical function analysis of VvSTS genes. The results show that VvSTS protein family members contain the same conserved domain CHS-like, similar physical and chemical properties, functional sites, secondary structure and tertiary structure, and their secondary structures are mainly composed of α-helixes and random coils; VvSTS don’t belong to secreted proteins, they are weak hydrophilic cytoplasm proteins; VvSTS gene promoters contain a variety of cis acting elements, it indicates that STS gene expression can be induced by a variety of factors; Vitaceae STS amino acid sequence alignment and genetic relationship analysis illustrate that Vitaceae STS have different degrees of similarities and this case conforms to the genetic relationship among species, and we further speculate that the function of Vitaceae STS could be the same.The second part includes codon adaptation index analysis of STS genes among different plants, sequence alignment and phylogenetic analysis of STS among species, as well as conservative domain analysis of STS in different species. These analyses show that STS of different plants contain a relatively conservative structure; phylogenetic tree demonstrates that STS evolution among different species accords with the evolutionary laws of species; conservative domain analysis of STS confirms that the evolutionary relationship among species is stable.After treatments of gibberellic acid, abscisic acid and ultraviolet radiation on grape leaves, the expression of VvSTS6 gene is measured by real-time PCR. The results indicate that GA stress, ABA stress and UV stress can promote the expression of VvSTS6. It manifests that VvSTS6 is responsive to these adversity stress signaling pathways and confirms that STS genes play roles in the process of anti-stress physiology in plants.Important information and valuable theoretical foundation are provided in this article for in-depth research of STS genes, as is a new idea for further study of other gene families with bioinformatics method.