The objective of the present study was to construct plant expression vectors containing chitinase genes and rootspecific promoters for resistance to phytopathogenic fungi. Chitinase genes with a signal peptide sequence, such as Chi42, syncodChi42-1, and syncodChi42-2, were used in this work. Chi42 is a wild-type gene of Trichoderma asperellum SH16, and both syncodChi42-1 and syncodChi42-2 genes are derived from Chi42, which have been optimized for the use of codon for plant expression. Methods of molecular cloning were applied in this study. The plant expression vectors pNHL20 containing chitinase genes, pNHL20.1 for Chi42, pNHL20.2 for syncodChi42-1, and pNHL20.3 for syncodChi42-2, were successfully constructed and transferred into Agrobacterium tumefaciens LBA 4404. Bacteria A. tumefaciens harboring the chitinase genes are ready for genetic transformation to peanuts (Arachis hypogaea L.) for subsequent applications.
Key words: Chitinase 42 kDa, Chi42, synthetic chitinase gene, root-specific promoter, Trichoderma asperellum