Promoters are bound by and why 1 Regulatory transcription fa

Promoters are bound by___ and why?

1. Regulatory transcription factors

2. General transcription factors

3. Translational regulatory proteins

4. Spliceosomes

5. Ribosomes

Solution

Ans:

Promoters are bound by Regulatory transcription factors

Genes transcribed by RNA polymerase II have two core promoter elements, the TATA box and the Inr sequence, that serve as specific binding sites for general transcription factors. Other cis-acting sequences serve as binding sites for a wide variety of regulatory factors that control the expression of individual genes. These cis-acting regulatory sequences are frequently, though not always, located upstream of the TATA box.

Example: two regulatory sequences that are found in many eukaryotic genes were identified by studies of the promoter of the herpes simplex virus gene that encodes thymidine kinase. Both of these sequences are located within 100 base pairs upstream of the TATA box: Their consensus sequences are CCAAT and GGGCGG (called a GC box). Specific proteins that bind to these sequences and stimulate transcription have since been identified.