BIOL 2311 Lecture Notes - Lecture 16: Adenine, Polynucleotide, Eukaryotic Transcription
RNA SYNTHESIS:
The nucleotide sequence in the transcribed mRNA is complementary to the base sequence in
DNA
RNA is copied from the template strand which is 3´-to- 5´ in the 5´-to-3´ direction = antiparallel
RNA synthesis does not require a primer and proceeds by the addition of nucleotides to form
mRNA chain
Promoter = nucleotide sequence 5´ to the transcription start site, which is the initial binding
site of RNA polymerase and transcription initiation factors
Promoter recognition by RNA polymerase is a prerequisite for transcription initiation
Many promoters contain a similar DNA sequence = TATAAT = “TATA” box (-10) is a consensus
sequence of many promoters
Consensus promoter sequence at -35 = TTGACA
Transcription termination sites are inverted repeat sequences which can form loops in RNA =
stop signal
Initiation
. Molecular machinery assembles at the promoter and begins synthesizing an RNA copy of the gene
The molecular machinery includes:
Transcription factors (TFs) that bind to the promoter in the area of a special sequence
known as the TATA box
RNA polymerase, an enzyme that catalyzes the assembly of RNA nucleotides into an
RNA strand
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Document Summary
The nucleotide sequence in the transcribed mrna is complementary to the base sequence in. Rna is copied from the template strand which is 3 -to- 5 in the 5 -to-3 direction = antiparallel. Rna synthesis does not require a primer and proceeds by the addition of nucleotides to form mrna chain. Promoter = nucleotide sequence 5 to the transcription start site, which is the initial binding site of rna polymerase and transcription initiation factors. Promoter recognition by rna polymerase is a prerequisite for transcription initiation. Many promoters contain a similar dna sequence = tataat = tata box (-10) is a consensus sequence of many promoters. Consensus promoter sequence at -35 = ttgaca. Transcription termination sites are inverted repeat sequences which can form loops in rna = stop signal. Molecular machinery assembles at the promoter and begins synthesizing an rna copy of the gene.