The Role of Basal Transcription Factors in Transcription Initiation

What are basal transcription factors?

Choose one: A. Proteins that assist in DNA replication B. Proteins involved in transcription initiation C. Proteins responsible for post-transcriptional modifications D. Proteins that regulate translation

Answer:

Basal transcription factors are proteins involved in transcription initiation (B).

Basal transcription factors play a crucial role in the initiation of transcription in eukaryotic cells. These factors are required for the assembly of the preinitiation complex, which includes RNA polymerase II and various transcription factors.

The preinitiation complex binds to the promoter region of a gene on the DNA template, marking the start site for transcription. Basal transcription factors help in positioning RNA polymerase II at the promoter and facilitating the unwinding of DNA strands to expose the template strand for transcription.

During transcription initiation, basal transcription factors act as scaffold proteins that stabilize the interaction between RNA polymerase II and the DNA template. They play a key role in the recruitment and assembly of the transcription machinery at the promoter region.

Once transcription initiation is complete and RNA polymerase II is ready to move into the elongation phase, certain basal transcription factors may dissociate from the preinitiation complex. This dissociation allows RNA polymerase II to proceed with elongation and synthesize the RNA transcript.