Sporophytes of Adiantum capillus-veneris were grown in a green house. Total RNA was prepared from the young leaves as described by Kanegae and Wada (1998). To purify poly(A)+ RNA, we used an mRNA purification kit (Amersham Pharmacia Biotech) according to the manufacturer’s instructions as described by Yamauchi et al. (2005). A cDNA library was constructed with Creator SMART cDNA library constructionkit (Clontech).