Can RNA polymerase unwind DNA?
Physical experiments have confirmed that RNA polymerase makes contact with these two regions when binding to the DNA. The enzyme then unwinds DNA and begins the synthesis of an RNA molecule. Then, the enzyme binds more tightly, unwinding bases near the −10 region.
How do you transcribe DNA?
It involves copying a gene’s DNA sequence to make an RNA molecule. Transcription is performed by enzymes called RNA polymerases, which link nucleotides to form an RNA strand (using a DNA strand as a template).
What is the correct sequence of steps that occur in protein synthesis?
Protein synthesis is the process in which cells make proteins. It occurs in two stages: transcription and translation. Transcription is the transfer of genetic instructions in DNA to mRNA in the nucleus. It includes three steps: initiation, elongation, and termination.
Is ATG a start codon?
The start codon is the first codon of a messenger RNA (mRNA) transcript translated by a ribosome. The most common start codon is AUG (i.e., ATG in the corresponding DNA sequence).
Is TAA a stop codon?
In the standard bacterial codon table, there are three stop codons, TAG, TGA, and TAA (UAG, UGA, and UAA on mRNA), which are recognized by two class I release factors, RF13 and RF2. In the few coding sequences available at that time, TAA was observed to be the most abundant stop codon.
What would happen if tRNA was non functional?
When a codon mismatch occurs, the ribosome will either abort or continue to translate the left codons. If a non-cognate amino acyl tRNA is incorporated, the peptide chain will lose specificity in the A site of the ribosome and the propagation of this error may result in premature of the peptide[28,33].
Where is tRNA after translation?
The tRNA carries the next amino acid in the polypeptide chain. The first tRNA transfers its amino acid to the amino acid on the newly arrived tRNA, and a chemical bond is made between the two amino acids. The tRNA that has given up its amino acid is released.
What are the three stages of translation?
Translation of an mRNA molecule by the ribosome occurs in three stages: initiation, elongation, and termination.