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.

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Do all proteins start with methionine?

Start codon AUG also codes for methionine and without start codon translation does not happen. And even the ambiguous codon GUG codes for methionine when it is first. So does this mean that all ...
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What is the criticality of the ribosome binding site relative to the start codon in prokaryotic translation?

In prokaryotic translation, how critical for efficient translation is the location of the ribosome binding site, relative to the start codon? Ideally, it is supposed to be -7b away from the start. ...
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How does translational coupling work in prokaryotes?

Today I heard about a phenomenon called "translational coupling", where the translation of one protein influences the translation of another protein. The messenger RNA levels don't seem influenced. ...
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Can DNA act as a translation substrate?

I get conflicting answers. One would think if it was true, it would be rather seminal and widely known. There are papers from Khorana[1], Holland[2], and Bretscher[3] (late 60s) that suggest that it ...
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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 ...
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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 ...
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Why is AUG the initiation codon?

Is there any reason why AUG is the initiation codon? Can’t translation start with different codons?
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How are there alternative initiation codons?

According to wikipedia and the original complete sequence of the K-12 genome, there are multiple non-AUG start codons such as GUG and UUG. How is this possible? I'm particularly curious about the ...
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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?
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Redundancy of the genetic code

One particular codon codes only for one amino acid, but an amino acid can be coded for by several different codons. Now according to the genetic code, the codon UUU ...
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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 ...
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Why is an initiator tRNA required, distinct from the methionine tRNA used in elongation?

I'm confused by why there is a need for different tRNA-methionine complexes for translational initiation and elongation. This paper mentions that It is important that each type of methionyl tRNA ...
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Mutation That Loses Stop Codon

Someone asked this in my class and my instructor wasn't sure in her answer, doesn't anyone know what happens in protein synthesis if a mutation causes mRNA to not possess a stop codon? Would the ...
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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 ...
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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 ...
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Why is an allele dominant or recessive? [duplicate]

Alleles refer to duplicate genes, where one allele can be dominant over the other. What makes an allele dominant or recessive, given that both code for a single protein?.
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Does the MS2 RNA binding protein have any translational repression effects?

Reposted from Quora: http://www.quora.com/Does-the-MS2-RNA-binding-protein-have-any-translational-repression-effects I'm thinking of the MS2 protein binding to its RNA hairpin target. Would the ...
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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". ...
Noob's user avatar
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Can ribosomes read ssDNA?

My question is whether translation can be done, either naturally or artificially, through a ribosome reading (single-stranded) DNA directly. If not, I would like to know what allows ssRNA to be ...
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Why is the DNA codon table "equal" to the RNA codon table

Before anything else please pay attention of the double quotes on the "equal" in the title - I know they are not equal, but you will understand in a bit. If I look at the DNA codon table ...
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Are there any examples in nature of two polypeptides joining into a single, continuous, third polypeptide?

Are there any examples in nature of two polypeptides join into a single, continuous, third polypeptide like this: (Where all the indicated amino and carboxyl groups are on the main polypeptide ...
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How can I tell if regulation is at the transcriptional or translational level?

I was reading a paper, http://www.pnas.org/content/109/8/E471.short, where the authors claim that (e475) Translation of the TfR (Transferrin Receptor) is regulated through sequences in the 3′ and 5′...
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Transcription and translation of prokaryotic operons

I'm taking a molecular genetics course, and we're currently discussing prokaryotic operons. The lacZ operon came up frequently for me as an undergraduate as an example for teaching regulatory control ...
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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?
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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, ...
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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 ...
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Do two compatible tRNA codons bond together?

Can two tRNA with complementary anti-codons link together? For instance UUU with AAA. If not, why not?
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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 ...
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Can human mRNA be translated in vitro by prokaryotes?

As the genetic code is universal, can mRNA from a human cell be correctly translated by a prokaryote in a in vitro translation system?
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What's the duration between the binding of adrenaline to β-AR and the first translated protein?

Binding of adrenaline (epinephrine) to the β-Adrenergic receptor leads to formation of cAMP (via G protein activation), activation of protein kinase A and subsequently to the expression of specific ...
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Stop codons and exons?

If we had a hypotheical gene called gene exampleGene and this gene had 5 exons, labeled A, B, C, D, and E in that order on the chromosome, could it be the case that the stop codon for this gene be on ...
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Is the start codon regarded as part of the UTR (untranslated region)?

The Wikipedia entry for Gene contains the statement: The transcribed pre-mRNA contains untranslated regions at both ends which contain a ribosome binding site, terminator and start and stop codons. ...
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Why are transcripts translated from 5' to 3' direction?

What is the mechanism? In other words, how does the tRNA know whether the codon is in 5' to 3' direction? I also heard that anything that is translated from 3' to 5' direction is degraded. Is it true?
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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 ...
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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?
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What is the Shine–Dalgarno sequence?

I am trying to understand the Shine–Dalgarno sequence. I currently know it is related to ribosomal binding sites, it is only found in prokaryote cells and it is in front of the initial codon. Also, ...
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Transport of newly synthesized proteins to cellular organelles

In the nucleus the DNA is transcribed and processed to mRNA which is translated into proteins in the cytoplasm. What happens between the time a protein is made and that when it reaches the cellular ...
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What is the advantage of the way eukaryotes initiate translation?

The eukaryote and prokaryote mechanism for translation is slightly different. Is there any advantage of the eukaryote translation mechanism ? Edit : I specifically want to know why eukaryotic ...
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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 ...
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Is it possible to express the cistrons from a polycistronic insertion fragment in a single plasmid?

I have a insertion fragment that I wish to express from pUC19 in Escherichia coli. The insertion fragment is a sub-section from a larger operon sequence and contains just the last two cistrons from ...
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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 ...
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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
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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 "...
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Why does azithromycin not affect human mitochondria?

Drugs like tetracyclines, macrolides and aminoglycosides bind to prokaryotic ribosomes. It is interesting that our body too having mitochondria, which have prokaryotic ribosomes, there is little(?) ...
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ATP required for cell processes [closed]

I haven't been able to find anything that tells me how much ATP is needed for DNA replication, transcription, and translation in humans, just papers that mention ATP used in those processes. I need ...
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Why do bacteria use formylated methionine in the initiator tRNA, while eukaryotes do not?

Could anyone suggest an explanation for the evolution of this trait in bacteria? Does it confer any advantage? It is also exploited by immunity receptors of some eukaryotes for the recognition of ...
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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 ...
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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 ...
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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 ...
the gods from engineering's user avatar
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Why is translation so much faster in prokaryotes than eukaryotes?

Prokaryotes perform transcription and translation much faster than eukaryotes. If memory serves, a single 70S prokaryotic ribosome can incorporate around 20 amino acids per second, whereas the 80S ...
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