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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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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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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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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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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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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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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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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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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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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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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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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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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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 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 here or in ...
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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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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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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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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 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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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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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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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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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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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 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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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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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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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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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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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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Identification of proteins in this animation of a ribosome translating mRNA

This gif is from this page After each aminoacyl-tRNA enters the ribosome, one blue thing comes and pushes the whole tRNAs whats that? I couldn't find it anywhere.(maybe some elongation factor?) Also ...
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How long does it take to form a peptide bond?

What is the time taken to form a peptide bond in vivo or in vitro? It isn't mentioned in my course on protein structures. I was just curious to find out if any time scale is known? Given that ...
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Do tRNAs that recognize multiple codons have any preference for one over another?

What are the effects of the different binding strength/affinity between the synonymous codons corresponding to a single tRNA ?
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How is mRNA directed out of the nucleus to its ultimate cytoplasmic location?

In the process of translation, I learnt that following formation the mRNA must exit the nucleus through a nuclear pore and attach to a ribosome. My question is how does mRNA navigate itself out of ...
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Codon tables and the wobble hypothesis

In E. coli, there are only 47 different tRNAs but 61 potential anticodons. This is because, from what I understand, the third base of the anticodon can pair by wobble rules. However, it is known that ...
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What physical force attracts the anti-codon on tRNA to the codon on mRNA during translation?

What physical force attracts the anti-codon on tRNA to the codon on mRNA during translation? I know that these two bond together, but what actually makes the tRNA move through the cytoplasm to the ...
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What is the translation termination efficiency in mammalian cells?

When I express proteins in bacteria I put at least two stop codons at the end of the gene to increase the termination efficiency. Is this the case in eukaryotic cells too? If I put a single stop codon ...
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How to interpret the relationships of PTMs from BioGRID's data

On BioGRID Database, PTMREL is a file that describes relationships of the PTMs (Post Translation Modification) tabulated in a PTMTAB file. I have several issues with this file. Foremost, I am not ...
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Has anyone ever sucessfully translated xRNA or yRNA? [closed]

I've recently been researching the subject of size-expanded nucleobases in alternative genetic sets. Many papers describe the, at least, partial success in replicating xDNA and yDNA, as well as ...
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Effect of a doubling of the start codon in a gene

I am learning about frameshift mutations. Frameshifts can occur due to a nucleotide deletion. Suppose that due to a frameshift, because of a deletion somewhere upstream from the original start codon, ...