Gene Function Analysis by Artificial MicroRNAs in Physcomitrella patens

MicroRNAs (miRNAs) are ~21nt long small RNAs transcribed from endogenous MIR genes which form precursor RNAs with a characteristic hairpin structure. MiRNAs control the expression of cognate target genes by binding to reverse complementary sequences resulting in cleavage or translational inhibition of the target RNA. Artificial miRNAs (amiRNAs) can be generated by exchanging the miRNA/miRNA* sequence of endogenous MIR precursor genes, while maintaining the general pattern of matches and mismatches in the foldback. Thus, for functional gene analysis amiRNAs can be designed to target any gene of interest.