What is the promoter region in prokaryotes?
What is the promoter region in prokaryotes?
Definition. A promoter is a region of DNA where transcription of a gene is initiated. Promoters are a vital component of expression vectors because they control the binding of RNA polymerase to DNA. RNA polymerase transcribes DNA to mRNA which is ultimately translated into a functional protein.
How does RNA polymerase bind to the promoter region in prokaryotes?
To begin transcribing a gene, RNA polymerase binds to the DNA of the gene at a region called the promoter. Each gene (or, in bacteria, each group of genes transcribed together) has its own promoter. A promoter contains DNA sequences that let RNA polymerase or its helper proteins attach to the DNA.
Which part of RNA polymerase recognizes the promoter region?
The melted part of the promoter bubble (right) is recognized through sequence-specific contacts with ssDNA. (B) View showing sequence-specific promoter elements and parts of RNAP recognizing them. RNAP shown as a gray transparent surface, except patches involved in sequence specific recognition of promoter DNA.
What is the function of the release factor during translation in eukaryotes?
What is the function of the release factor during translation in eukaryotes? It releases the ribosome from the ER to allow polypeptides into the cytosol. It supplies a source of energy for termination of translation. It binds to the stop codon in the A site in place of a tRNA.
What is the product of translation phase?
polypeptide
What event occurs during translocation?
In the elongation cycle of translation, translocation is the process that advances the mRNA–tRNA moiety on the ribosome, to allow the next codon to move into the decoding center.
What happens before translocation?
Basic Characteristics of Translocation In each round of elongation, two tRNA molecules together with the mRNA move through the ribosome in a multistep process called translocation. In parallel, deacylated tRNA moves from the P site to the E (exit) site before dissociating from the ribosome.
What is the role of RNA polymerase in eukaryotic cells?
As previously discussed, distinct RNA polymerases are responsible for the transcription of genes encoding ribosomal and transfer RNAs in eukaryotic cells. Transcription of these genes yields a large 45S pre-rRNA, which is then processed to yield the 28S, 18S, and 5.8S rRNAs (Figure 6.15).