Question

A nucleotide sequence (consensus TTGACA) in prokaryotic promoters to which the sigma factor of RNA polymerase binds during the initiation of transcription.

Answer 1

The -35 sequence TTGACA in prokaryotic promoters is bound by sigma factor, an essential step in transcription initiation. This interaction allows the RNA polymerase to bind, leading to DNA unwinding and the beginning of transcription.

Step-by-step explanation:

The TATA box and TTGACA sequences in prokaryotic promoters are critical for the initiation of transcription in prokaryotic cells. The TTGACA sequence is commonly referred to as the -35 sequence and, along with the TATA box, these consensus sequences are bound by the sigma factor (o) of RNA polymerase. This interaction is essential for the transcription machinery to bind to the DNA, leading to the unwinding of the DNA template at the A-T-rich -10 region and the starting of transcription with the synthesis of abortive transcripts.