Isolation and Expression Profiling of Gene Encoding Chalcone Synthase in Ceratopteris thalictroides

Chalcone synthase (CHS) is a key enzyme in the synthesis of plant flavonoids. However, information on CHS genes in ferns is still unclear. In this study, rapid amplification of cDNA ends (RACE) was used to isolate the full-length sequence of the CHS gene from model fern Ceratopteris thalictroides (CtCHS, GenBank accession number: JX027616.1). Sequence analysis showed that the full length of the CtCHS gene was 1616 bp, with three exons and two introns. Its ORF region was 1215 bp, encoding 404 amino acids. Phylogenetic analysis indicated that CtCHS was clustered with the other ferns, including Equisetum arvense, Psilotum nudum and three leptosporangiate ferns, which reflected the monophyletic feature of the ferns according to Smith's system. Western blot analysis showed that the expression of this gene was significantly affected by ultraviolet (UV) treatment. In this study, the full-length sequence of CtCHS was cloned and the function of the CtCHS protein was studied, thus providing molecular information for further studies on the effect of CtCHS on flavonoids production.