A researcher uses RNA interference (siRNA) to knock down expression of gene X in cultured human cells. Western blot is performed to measure protein X levels in: (1) untreated cells, (2) cells transfected with X-targeting siRNA, (3) cells transfected with scrambled (control) siRNA. After 48 hours, cell proliferation is measured.
Why is the scrambled siRNA control essential?
- A
To eliminate cell death
- B
To increase X protein levels
- Ccheck_circle
To distinguish specific knockdown effects from generic effects of siRNA transfection
- D
To replace siRNA with another molecule
Explanation
Transfection itself can stress cells and alter gene expression. The scrambled control matches all conditions except sequence specificity. Differences between X-siRNA and scrambled samples are attributed to specific X knockdown.