The DNA sequence below gives the first 12 base pairs of the transcribed region of a gene, and the template and nontemplate strands of DNA are identified. The transcription start is the thymine nucleotide at the end of the sequence given. Use the diagram to answer the list of questions. Make a copy of the diagram before you begin answering the questions, or have one group member diagram the answers for bacteria and another group member diagram the answers for eukaryotes. Nontemplate strand ___________TTGCTACGGTCA___________
Template strand ___________AACGATGCCAGT___________
Write the anticipated bacterial consensus sequence(s) in the approximate position(s) on the diagram.

Verified step by step guidance

1. Identify the transcription start site, which is the thymine nucleotide at the end of the sequence provided. This will help you orient the sequence and determine the upstream and downstream regions.
2. Understand that bacterial promoters typically contain two conserved regions: the -10 region (Pribnow box) and the -35 region. These regions are located upstream of the transcription start site and are critical for RNA polymerase binding.
3. Determine the approximate positions of the -10 and -35 regions relative to the transcription start site. The -10 region is approximately 10 base pairs upstream, and the -35 region is approximately 35 base pairs upstream of the transcription start site.
4. Write the bacterial consensus sequences for the -10 and -35 regions. The -10 consensus sequence is typically 'TATAAT', and the -35 consensus sequence is typically 'TTGACA'. These sequences may vary slightly depending on the specific bacterial species.
5. Place the consensus sequences in the appropriate positions on the nontemplate strand of the DNA diagram. The -10 sequence should be approximately 10 base pairs upstream of the transcription start site, and the -35 sequence should be approximately 35 base pairs upstream.

Key Concepts

Transcription in Prokaryotes

Transcription in prokaryotes occurs in the cytoplasm and involves the synthesis of RNA from a DNA template. The process begins when RNA polymerase binds to the promoter region of a gene, unwinding the DNA strands. The nontemplate strand serves as the coding strand, while the template strand is used to synthesize the complementary RNA. Understanding this process is crucial for identifying consensus sequences that guide RNA polymerase binding.

Consensus Sequences

Consensus sequences are short, recurring patterns in DNA that are crucial for the binding of transcription factors and RNA polymerase. In prokaryotes, the most well-known consensus sequences are the -10 (Pribnow box) and -35 regions, which are located upstream of the transcription start site. These sequences help ensure the efficient initiation of transcription by providing a recognizable site for the transcription machinery.

Template and Nontemplate Strands

In the context of DNA transcription, the template strand is the DNA strand that is read by RNA polymerase to synthesize RNA, while the nontemplate strand, also known as the coding strand, has the same sequence as the RNA produced (except for thymine being replaced by uracil). Understanding the roles of these strands is essential for accurately determining the RNA sequence and identifying the corresponding consensus sequences in the given DNA.