Abstract
The moss Physcomitrella patens is an excellent model plant in the reverse genetics because high efficiency-gene targeting is applicable to this moss. In this study, we have developed a gene silencing system using artificial micro RNA (amiRNA). Micro RNAs are approximately 21-nt. The secondary structures of miR319 precursor transcripts from Arabidopsis and Physcomitrella are highly conserved. AmiRNA from Arabidopsis miR319a has been successful in the suppression of gene expression (Schwab et al. 2006). To develop a gene silencing system using amiRNA, we constructed the stable moss transgenic line that constitutively expressed a nucleus localized GFP fusion protein. Then, we designed an amiRNA to target the GFP gene and constructed a plasmid consisting of the amiRNA precursor sequence and actin or CaMV35S promoter. The amiRNA constructs were introduced into the moss by particle bombardment and we examined whether the expression of GFP in the transgenic line was transiently suppressed. These results will be presented.
