Scientists investigated the function of a eukaryotic transcription factor called TBP (TATA-binding protein). This protein is essential for recruiting RNA polymerase II to eukaryotic promoters to initiate the transcription of protein-coding genes.
The scientists treated cultures of human cells in four different ways:
The scientists then measured the percentage of cells that were successfully transcribing a major reporter gene. Their results are shown in the table below:
| Cell treatment | Percentage of cells with active transcription |
|---|---|
| Treatment P (Control) | 91%91\%91% |
| Treatment Q (Antibody to TBP) | 15%15\%15% |
| Treatment R (siRNA against TBP) | 11%11\%11% |
| Treatment S (siRNA + exogenous TBP) | 89%89\%89% |
Suggest explanations for the results of Treatment Q, Treatment R, and Treatment S.
