Comparison Of Differential Genes Between FOC1 And FOC4 And Function Analysis Of The Gene Acetolactate Synthase Catalytic Subunit

Bananas are one of the important fruits in the world, and it is an important pillar of the agriculture economy, mainly grown in China's southern provinces. In recent years, the Fusarium oxysporum f. Sp. Cubense(FOC)caused by Fusarium wilt on China and the world banana industry caused a great threat, and we causative factor for Fusarium oxysporum the regulation mechanism is poorly understood. A major disadvantage is caused by Fusarium oxysporum Race 1 for ‘Gros Michel'(Musa sp. AAA group) and ‘Pisang Awak'(Musa sp. AAB group).But Race 4 can infect almost all banana varieties. In view of the so many differences between Race 1 and Race 4 about virulence and host range, selected the different Genes Putatively Involved in virulence and host range, then further research the gene function, and this is so important to provide a theoretical basis for the development of new ways of prevention.We compared the genes and proteins for selecting the different genes?proteins and secreted proteins between FOC1 and FOC4.Then the genes?proteins were functionally annotated to the known databases including Gene Ontology(GO),Kyoto Encyclopedia of Genes and Genomes(KEGG). By analyzing these results, we analyzed nine specifical genes about important signaling pathway what we selected out before in FOC4 and ten genes related to virulence have been reported by quantitative real-time PCR and bioinformatics analysis.Acetolactate synthase catalytic subunit gene contains an open reading frame(ORF)of 1086 bp and encodes 362 amino acids with three conserved domains, named Pyrimidine(PYR) binding domain of POX and relate proteins, Thiamine pyrophosphate enzyme, Thiamine pyrophosphate(TPP) enzyme family respectively.Phylogenetic analysis showed that the gene is relatively conserved in a few species of Fusarium fungi, and the proteins were high similarity. By bioinformatics softwares we found that the proportion of ?- helix, ?- fold, and cyclic structures in the whole of the protein is accounted for 32.60%, 14.92%, 52.49%, there is a coiled-coil structure and 13 sites for DNA binding in it, also it is a unstable transmembrane protein.To generate the knockout mutants ? Fo ALSCS, the upstream and downstream sequences of the genes were amplified by PCR,and fused with the hph gene encoding hygromycin resistance. Through a large number of phenotype experiments, we found that aerial hyphae wrer more compact than that of WT, but the growth rate, sporulation rate was significantly decreased. Further, they have similar sensitivity to Congo Red,Calcofluor White and H2O2. Transcription analysis showed that there was no significant difference between the mutant and WT in the genes related to ALS. The ALS activity texting show FOC4 wild type has the highest activity, but the ALS activity of the mutation was opponent. Virulence tests showed that the Acetolactate synthase catalytic subunit are required for the full virulence of F. oxysporum f. sp. Cubense Race 4.In conclusion, this study may serve as a basis for understood the difference pathogenic mechanism between Fusarium oxysporum Race 1 and Race 4,and may offer a new thought for the development of new safe and efficient fungicide.