Fig. 2.

Schematic of important features and parameters in the small interfering RNA (siRNA) design. General important features for an optimal siRNA design (upper boxes) and the identification of optimal messenger RNA (mRNA) target positions (lower box) are described. The scheme of the double-stranded siRNA (center; red, ‘sense’ or ‘passenger’ strand; blue, ‘antisense’ or ‘guide’ strand) shows the characteristic deoxyribonucleic acid overhangs at the 3′-end (e.g., dT; black circles), but does not include any chemical modifications (for details, see below). dsRNA double-stranded RNA, miRNA microRNA, ORF open reading frame, UTR untranslated region