Molecular Cloning and Expression Analysis of a Terpene Synthase Gene, HcTPS2, in Hedychium coronarium

The Hedychium coronarium can emit a strong scent which is mainly composed of monoterpenes. A cDNA clone, HcTPS2 (H. coronarium terpene synthases), was cloned from H. coronarium flower. The gene has an open reading frame of 1,788 bp which encodes a protein of 596 amino acids with a calculated molecular mass of 66.7 kDa. The deduced amino acid sequence shows 35-38% identity with known monoterpene synthases in other angiosperm species. HcTPS2 was appreciably expressed in the petals, sepals, and stamens of H. coronarium, whereas no expression signal was detected in those of nonscented species. To the best of our knowledge, this is for the first time to clone the terpene synthase gene from H. coronarium, which provides the basis for biotechnological manipulation of scent composition in H. coronarium.