The Expression Analysis And Cloning Of The Related Genes In Formation Of Scleritum Of Rhizoctonia Solani

Rhizoctonia solani, a group of important plant pathogenic fungi, can cause serious disease in a variety of crops, such as rice and wheat. Reports had been made about the mechanism of formation and development of the sclertium of Rhizoctonia solani, but the main focus of these reports was on nutrition and environmental factors. Despite some useful research, there is still lack of the knowledge on the molecular mechanism of sclerotium formation of Rhizoctonia solani, the sclertium formation-related genes are still yet to be found.In this study, real-time quantitative PCR system was used to detect the gene expressions of A, B, C, E, F(two-component response regulator, macrophage activating glycoprotein, extracellular elastionolytic metalloproteinase, Cyclophilin, ER-derived vesicles protein ERV29) in Rhizoctonia solani, in which total RNAs from different growing stages were used as templates and18SrRNA as reference gene. The results showed that the five genes were down-regulated at the initiation of sclerotia and decreased gradually until formation of sclertium, but the genes expression increased quickly from formation of sclertium to maturation. These genes expressions remained a contant after maturation of sclerotia. It was shown that the five genes expression alter significantly among different growing stages of Rhizoctonia solani.In order to clarify the biological functions of genes expressions alter significantly among different growing stages of Rhizoctonia solani. RACE are carried out to clone the3’ and5’end of the cDNA respectively. A684bp cDNA completed sequence. The cDNA sequence of Rs-CYP we obtained contains a315bp open reading flame(ORF) flanked by a complete250bp5’untranslated region and119bp3’untranslated region. The ORF encodes a putative104amino acid protein with sever characteristic highly conserved regions, which are in agreement with the characteristic of CYP. By BLASTing the database, gene sequence has high homology with other fungi CYP, the result proves amplified gene are Rhizoctonia solani AG-1IA CYP. The phylogenetic tree based on the amino acid sequences showed that genetic relationship between Rhizoctonia solani AG-11A and Moniliophthora perniciosa was closest. The cloning and sequencing of Rs-CYP gene lays a good foundation for the future work on the biological functions of CYP and the molecular mechanism of the sclertium formation in Rhizoctonia solani.