Skip to main content

Questions tagged [translation]

Translation is the process of protein synthesis. The information encoded in the mRNA is translated into an amino acid sequence through the joint activity of tRNAs and ribosomes.

Filter by
Sorted by
Tagged with
5 votes
2 answers
481 views

How can good Shine–Dalgarno or Kozak sequences enhance translation?

In prokaryotes the Shine-Dalgarno sequence, a polypurine consensus sequence near the initiation codon (usually AUG), is required for the mRNA to bind to the small ribosomal subunit, allowing ...
3 votes
3 answers
445 views

why does translation occur more frequently than transcription?

In our textbook it says that translation occurs more in a cell than transcription but I couldn't find anything that explains why it happens
2 votes
1 answer
89 views

In mRNA translation, why are there so many factors?

When the small ribosomal subunit binds to mRNA’s 5’-cap, it looks for the complex of three eLFs bound to the poly-A-binding protein (PABP), which circularises the mRNA. It is then this circular mRNA ...
0 votes
0 answers
27 views

Speed of cell signal to protein production

How long does a cell take to make a protein from the point of receiving the signal to produce the protein? Does the cell have stores of the protein ready to release or is the protein created in real-...
1 vote
0 answers
121 views

If the very first codon of an mRNA strand is a start codon (ie, AUG) does no 5' UTR exist?

Apologies if this is too basic of a question, but from what I've learned all mature mRNA strands have both a 5' and 3' UTR. Normally this is just because the start codon has not appeared yet. However, ...
2 votes
1 answer
190 views

Why is the codon size three, rather than four? [duplicate]

The genetic code consists of triplets, each of which (apart from the stop codons) yields an amino acid when the mRNA is translated. But why did triplets evolve, rather than a longer or shorter codon ...
0 votes
0 answers
39 views

Are all proteins translated by the RER ribosomes destined for the Golgi apparatus?

The proteins translated by the free ribosomes can fold in the cytoplasm and never go through the endomembrane system. But when the endomembrane system is described, it is always stated that the ...
2 votes
1 answer
69 views

Does a gene need to be transcribed for every single protein made? [duplicate]

There is one set of DNA in the nucleus and one instance of any particular gene. That gene is transcribed into mRNA and then it is translated by a ribosome. A cell has millions of ribosomes. So it ...
2 votes
1 answer
151 views

What percentage of our DNA is never transcribable? What percent is never actually transcribed into RNA unless researchers force it to in a lab?

From what I gather, the vast majority (but not all) of the DNA in our genomes will transcribe and create an RNA, if only under certain conditions in a lab (forcibly unwound, among other steps). How ...
1 vote
1 answer
43 views

"mutant" codon translations?

AFAIK codon->protein translation is pretty much universal (very few exceptions). I've seen people explaining this means every living organism descends from the same ancestral. That's certainly a ...
2 votes
1 answer
251 views

How does the tRNA recognise the first methionine during translation?

The process of translation starts with the initiator tRNA identifying the codon coding for methionine (AUG). However, my textbook also says that there are various untranslated regions present on the ...
0 votes
1 answer
99 views

Confusion regarding the meaning of the coding strand of DNA [duplicate]

I am having problems getting the ‘correct’ answer for the above question. I am assuming that mRNA uses the template strand (not the coding strand) for protein synthesis. So: ...
1 vote
1 answer
80 views

Aminoacyl-tRNA synthetase and the degeneracy of the genetic code

Aminoacyl-tRNA synthetase catalyses the covalent linkage of amino acids to tRNA. The aminoacylated tRNA is then bound to mRNA on the ribosome in a codon–anticodon hydrogen bonded interaction. In ...
2 votes
2 answers
238 views

Does an N1-methyl-pseudouridine substitution in the first codon position (in mRNA) result in a different amino acid?

Because of the possibility of ‘wobble’ in the base-pair made between the third (5’) position of the anticodon and the third (3’) base of the the mRNA codon , single tRNAs with appropriate bases in ...
7 votes
2 answers
529 views

What prevents non-aminoacylated tRNA from binding to mRNA on the ribosome and disrupting protein synthesis?

Specific aminoacyl-tRNA synthetases catalyse a reaction in which a transfer RNA molecule with a given anticodon is covalently attached to its cognate amino acid (aminoacylated). What factors favor the ...
4 votes
2 answers
808 views

Can different proteins be produced during translation of a single mRNA in eukaryotes?

Is there a translational mechanism that eukaryotes can use to produce different proteins from a single transcribed mRNA?
8 votes
5 answers
18k views

RNA or ribosome, which one moves during translation?

During translation ribosomes decode the genetic information present in the mRNA and protein synthesis takes place. During this process which of those two does move, the ribosome or the mRNA?
6 votes
1 answer
5k views

Can mRNA be used by ribosomes more than once?

Can mRNA be used by ribosomes more than once? I mean can mRNA be translated more than one time? If not what will happen to it after translation?
0 votes
1 answer
2k views

How to memorize Transcription and Translation? [closed]

I often get confused between transcription and translation. Is there any way to memorize them easily like a mnemonic??
0 votes
0 answers
56 views

Do transcription factors need to undergo extensive post-translational modification?

Some proteins need additional processing to become fully functional, for example NiFe-hydrogenases need to be cleaved by endopeptidases for some of their subunits to be active. Is it known whether ...
2 votes
0 answers
52 views

How does the phosphorylation state of 4E-BPs affect translation of nuclear-encoded mitochondrial transcripts?

A 2020 review paper about mTOR (ref. 1) says: because biomass accumulation demands vast reserves of energetic currency, mTORC1 enhances translation of nuclear-encoded mitochondrial transcripts ...
0 votes
1 answer
82 views

Why does miRNA not get translated?

If miRNA and mRNA are made of the same nucleotides, then why are miRNA not translated like mRNA? Is it due to miRNA lack of start codon? Or lack of promoters? Has it got anything to do with RISC?
4 votes
1 answer
4k views

How does aminoacyl-tRNA synthetase recognize different tRNAs?

There are about 20 aminoacyl-tRNA synthetases, one for each amino acid. Each aminoacyl-tRNA synthetase has a binding site that recognizes a specific amino acid, and other binding areas that recognize ...
7 votes
2 answers
154 views

Why are there two replicase proteins translated from tobacco mosaic virus RNA?

I’m trying to understand how TMV is expressed and have read (here) that there is a large and small form of the RNA-dependent RNA replicase. These are translated from the same region of the genome, the ...
3 votes
3 answers
291 views

dsDNA translation

Since DNA is double stranded and each strand is complementary to the other, the codons on each strand will come out to be different after transcription(depending on the reading frame). Does this mean "...
2 votes
2 answers
863 views

How do mRNAs find ribosomes?

After mRNA is released from the nucleus, the next process is its translation by ribosomes. By what physical, chemical or biochemical process does the mRNA reach the ribosome in the cytoplasm?
1 vote
1 answer
579 views

How is Open Reading Frame (ORF) chosen?

I understand that AUG is the "start codon", and, because of this, most proteins begin with methionine as their first amino acid. However, this ORF problem on Rosalind.info states that "...
2 votes
1 answer
109 views

How do ribosomes interpret stop codons as selenocysteine and pyrrolysine?

How does the protein synthesising machinery determine that UGA and UAG in mRNA should be decoded as selenocysteine and pyrrolysine, respectively, in certain circumstances, rather than as stop codons?
5 votes
1 answer
2k views

How to determine the most likely reading frame of a DNA sequence?

This question is from a past exam paper for an introductory bioinformatics module. I'm a computer scientist doing biology for the first time. "A short bacterial gene has been sequenced, giving the ...
1 vote
1 answer
69 views

How to estimate mRNA counts from Relative Promoter Units (RPU) or RNAP per second (PoPS) in E. coli?

I need a rough estimate on how to translate RPU or Polymerases Per Second (PoPS) to mRNA count (or even better protein count) in E. coli. I understand that any number we come up with will be a very ...
6 votes
2 answers
842 views

From which end of mRNA does transcription start?

The book "Understanding bioinformatics", says that "RNA polymerase transcribes the anticoding strand in the direction from 3' to 5', so that the mRNA strand is produced from the 5' to the 3' end". ...
1 vote
1 answer
61 views

What prevents mRNAs that are localized to a specific part of the cell from being translated before they reach their destination?

One of the methods of mRNA localization, for example, is random diffusion of mRNAs where the mRNA binding proteins are localized to a certain part of the cell. However, I was taught that the ribosome ...
1 vote
2 answers
2k views

How to find the amino acid in the DNA protein

3' A T A G T A C C G C A T G T A C G G G C G A G A C A T T C G A G C A T T C A T 5' This a Template DNA. How to find the number of amino acids amino acids ...
2 votes
1 answer
203 views

The genetic code and the effect of point mutations on proteins

I was asked a question, "Considering degenerate and non ambiguous nature of genetic code, Why is that certain mutations don't disturb the protein synthesis leading to synthesis of functional proteins ...
3 votes
1 answer
333 views

The shape of mRNA

I was wondering about the shapes assumed by mRNA. I have read some sources quoting that it is linear (quora, so not very reliable) and also a source that says a hairpin shape is common (nature, so I ...
2 votes
1 answer
111 views

How does a ribosome gather tRNAs at a fast enough rate for Translation?

There are many animations of the ribosome in action, and all I have seen show the correct tRNA neatly entering the ribosome and its amino acid being added to the growing protein chain. My question is ...
1 vote
2 answers
1k views

Is there an Exit site (E-site) on the eukaryotic ribosome?

One of my professors mentioned something about the e-site (the exit site for the t-RNA) on a eukaryotic ribosome. There was a student in the class who objected, saying that there is no e-site on ...
4 votes
1 answer
214 views

How does a ribosome move along mRNA?

I've been reading around Wikipedia recently trying to learn more about various biomechanisms. I’m intrigued by ribosomes — with how small they are, they’re basically chemical machines from what I can ...
0 votes
0 answers
73 views

Could Wobble Base Pairing ultimately yield an amino acid that was originally uncalled for or not expected?

How does the cell choose which amino acid to attach to tRNA when there is wobble base pairing involved (not the other way around)? Consider the example below. For the purpose of this question I'm ...
6 votes
5 answers
28k views

How much nucleoside triphosphate is required to form one peptide bond during protein synthesis?

I'm trying to find out how many molecules of nucleoside triphosphates (ATP, GTP, UTP and/or CTP) it takes to release enough energy to link two amino acid monomers together with a peptide bond, ...
4 votes
2 answers
236 views

Are mitochondrial genes decoded in the same way as nuclear genes?

Mammalian mitochondrial genomes contain only 22 tRNA-coding genes, which is an insufficient number to decode mRNAs under the standard wobble rules. How is translation of mitochondrial mRNAs achieved ...
2 votes
1 answer
450 views

Does every protein starts with Methionine amino acid [duplicate]

During process of protein synthesis we need AUG Codon to start translation .As we know this codon codes for Methionine amino acid so can we say that every protein starts with Methionine amino acid ?
12 votes
4 answers
16k views

Why is AUG the initiation codon?

Is there any reason why AUG is the initiation codon? Can’t translation start with different codons?
3 votes
1 answer
349 views

Why did translation develop a specific codon for initiation?

The translation of mRNA is initiated by a specific methionine-accepting tRNA at a specific initiation codon, usually AUG (complementary to the tRNA anticodon). However translation at suitable (albeit ...
1 vote
3 answers
3k views

Why are there three stop codons but only one start codon?

I was wondering whether there is any specific reason that there are three stop codons but only one start codon in prokaryotic and eukaryotic cytoplasmic mRNAs.
3 votes
1 answer
744 views

Relationship between the ambiguity (wobble) at codon position 3 in elongation and codon position 1 in initiation

In prokaryotes the usual observed start codon frequency is AUG > GUG > UUG. An explanation for this is that AUG is the most common initiator codon because it forms the most stable interaction with ...
8 votes
1 answer
8k views

The GUG start codon in E. coli: identity of initiating tRNA and efficiency of translation

Translation in E. coli is usually initiated at an AUG codon, which encodes the amino acid methionine. In some cases, however, the start codon is GUG, which normally encodes valine. If GUG is used as ...
14 votes
3 answers
2k views

How did the genetic code evolve?

The genetic code is redundant, there are 20 amino acids for 64 possible nucleotide combinations (triplet codons). Therefore some amino acid are coded by several different codons. While leucine is ...
1 vote
1 answer
1k views

Do ribosomes read mRNA?

So I understand that tRNA bonds to a codon (with an anticodon) in the translation process. I read in my biology textbook that the ribosomes "read" the mRNA strand. Why do the ribosomes need to read ...
13 votes
2 answers
612 views

Are codons that map to the same amino acids interchangeable?

From wikipedia, in the section on the RNA codon table, I see a mapping between codons and amino acids. There, Valine is related to GUU, GUA, GUG, GUC. Does it mean in the same context that these ...