Which of the following are involved in the initiation of translation?
Which of the following are involved in the initiation of translation? RNA polymerase, complementary base pairing, the synthesis of a nucleic acid, and the formation of bonds in a sugar-phosphate backbone.
What is translation initiation?
Translation initiation is a complex process in which initiator tRNA, 40S, and 60S ribosomal subunits are assembled by eukaryotic initiation factors (eIFs) into an 80S ribosome at the initiation codon of mRNA. Initiation on a few mRNAs is cap-independent and occurs instead by internal ribosomal entry.
What stimulates translation initiation?
The Mechanism of Translation Initiation Initiation on a few mRNAs occurs by noncanonical mechanisms, of which the most common is 5′-end independent internal ribosomal entry. eIF1A and eIF3 promote dissociation of the 80S ribosome into 40S and 60S subunits (Step 1).
What are the steps in the process of translation?
Steps of Translation There are three major steps to translation: Initiation, Elongation, and Termination. The ribosome is made of two separate subunits: the small subunit and the large subunit. During initiation the small subunit attaches to the 5′ end of mRNA. It then moves in the 5′ → 3′ direction.
What is the main product of translation?
The product of transcription is RNA, which can be encountered in the form mRNA, tRNA or rRNA while the product of translation is a polypeptide amino acid chain, which forms a protein.
Is transcription or translation first?
Cell uses the genes to synthesize proteins. This is a two-step process. The first step is transcription in which the sequence of one gene is replicated in an RNA molecule. The second step is translation in which the RNA molecule serves as a code for the formation of an amino-acid chain (a polypeptide).
Does translation occur first?
RNA then leaves the nucleus and goes to a ribosome in the cytoplasm, where translation occurs. Translation reads the genetic code in mRNA and makes a protein. Transcription is the first part of the central dogma of molecular biology: DNA → RNA. It is the transfer of genetic instructions in DNA to messenger RNA (mRNA).
What are the steps of DNA transcription?
Transcription involves four steps:
- Initiation. The DNA molecule unwinds and separates to form a small open complex.
- Elongation. RNA polymerase moves along the template strand, synthesising an mRNA molecule.
- Termination. In prokaryotes there are two ways in which transcription is terminated.
- Processing.
Where is translation process located?
ribosomes
What are the three basic stages of transcription?
Transcription takes place in three steps: initiation, elongation, and termination. The steps are illustrated in Figure 2.
What happens to mRNA after transcription?
Once mRNAs enter the cytoplasm, they are translated, stored for later translation, or degraded. mRNAs that are initially translated may later be temporarily translationally repressed. All mRNAs are ultimately degraded at a defined rate.
What is the role of mRNA in transcription?
mRNA is “messenger” RNA. The process of making mRNA from DNA is called transcription, and it occurs in the nucleus. The mRNA directs the synthesis of proteins, which occurs in the cytoplasm. mRNA formed in the nucleus is transported out of the nucleus and into the cytoplasm where it attaches to the ribosomes.
What are the steps of mRNA processing?
Section 11.3Regulation of mRNA Processing. As explained in the previous sections, conversion of a 5′ capped RNA transcript into a functional mRNA involves two primary steps: (1) cleavage and polyadenylation at the 3′ end and (2) ligation of exons with the concomitant excision of introns, or RNA splicing.
What happens during mRNA processing?
This transcript must undergo processing (splicing and addition of 5′ cap and poly-A tail) while it is still in the nucleus in order to become a mature mRNA. The mature mRNA is exported from the nucleus to the cytosol, where it is translated at a ribosome to make a polypeptide.
Does bacterial mRNA requires processing?
1. Synthesis of bacterial mRNAs. Bacterial mRNAs do not undergo any significant forms of processing: the primary transcript that is synthesized by the RNA polymerase is itself the mature mRNA, and its translation usually begins before transcription is complete (Figure 10.1).