Characterization and expression of chalcone synthase gene from Ginkgo biloba

The genomic DNA sequence of chalcone synthase (CHS) gene was cloned from Ginkgo biloba. The Gbchs was 1295 bp long and composed of two exons and one intron, one of the typical features of chalcone synthase genes. The genomic Southern blot analysis indicated that Gbchs belonged to a multigene family. RT-PCR analyses revealed that Gbchs expressed differentially in the root, stem and leaf tissues of G. biloba, and the expression was induced by UV-B and wounding treatments. The recombinant GbCHS protein was successfully expressed in Escherichia coli strain M15 [pREP4] with pQE30 vector and the result showed that the expressed GbCHS protein had molecular weight of about 42 kDa, a size matching that of the predicted by bioinformatic analysis. This study provides useful information for further studying this gene and its function in ginkgo flavonoids biosynthetic pathway in G. biloba, the so-called “living fossil” plant possessing many pharmaceutical properties for human health.