What is the difference between siRNA and shRNA?

Small interfering RNA (siRNA) and short hairpin RNA (shRNA) are both short RNA molecules used in RNAi applications to knock down gene expression, but they have several differences:

Structure: siRNA is a double-stranded RNA molecule, while shRNA is folded into a stem-loop structure.

Processing: siRNA is delivered directly to the cytosol, while shRNA is processed within the cell and undergo enzymatic cleavage to form siRNA.

Effect: siRNA's effect is transient, with an effect duration of about 48-72 hours, while shRNA can integrate into the cellular genome via vectors and maintain sustained expression.

Off-target effects: shRNA constructs can have less off-target effects than siRNA.

Potency: Optimized shRNA constructs can have high potency and sustainable effects.

If the targets obtained by siRNA, and used for shRNA, the interference efficiency of siRNA cannot be completely equivalent to that of shRNA because shRNA still needs to beprocessed and cut to play a role.