Eukaryotic elongation factors
Encyclopedia
Eukaryotic elongation factor
s are very similar to those in prokaryotes
.
Elongation in eukaryotes is carried out with two elongation factors: eEF-1
and eEF-2.
Elongation factor
Elongation factors are a set of proteins that facilitate the events of translational elongation, the steps in protein synthesis from the formation of the first peptide bond to the formation of the last one.Elongation is the most rapid step in translation:...
s are very similar to those in prokaryotes
Prokaryotic elongation factors
In prokaryotes, three elongation factors are required for translation: EF-Tu, EF-Ts, and EF-G.*EF-Tu mediates the entry of the aminoacyl tRNA into a free site of the ribosome....
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Elongation in eukaryotes is carried out with two elongation factors: eEF-1
EEF-1
eEF-1 is a eukaryotic elongation factor.Its α and βγ subunits act as counterparts to EF-Tu and EF-Ts, respectivelyGenes include:* EEF1A1, EEF1A2, EEF1A3* EEF1B1, EEF1B2, EEF1B3, EEF1B4* EEF1D, EEF1E1, EEF1G...
and eEF-2.
- The first is eEF-1, and has two subunits, α and βγ. α acts as counterpart to prokaryotic EF-TuEF-TuEF-Tu is one of the prokaryotic elongation factors.The prokaryotic factor EF-Tu mediates the entry of the aminoacyl-tRNA into a free site of the ribosome. EF-Tu functions by binding an aminoacylated, or charged, tRNA molecule in the cytoplasm...
, mediating the entry of the aminoacyl tRNA into a free site of the ribosomeRibosomeA ribosome is a component of cells that assembles the twenty specific amino acid molecules to form the particular protein molecule determined by the nucleotide sequence of an RNA molecule....
. βγ acts as counterpart to prokaryotic EF-TsEF-TsEF-Ts is one of the prokaryotic elongation factors.EF-Ts serves as the guanine nucleotide exchange factor for EF-Tu , catalyzing the release of guanosine diphosphate from EF-Tu...
, serving as the guanine nucleotide exchange factorNucleotide exchange factorNucleotide exchange factors are proteins that stimulate the exchange of nucleoside diphosphates for nucleoside triphosphates bound to other proteins.-Function:...
for α, catalyzing the release of GDP from α.
- The second elongation factor is eEF-2, the counterpart to prokaryotic EF-GEF-GEF-G or elongation factor G is one of the prokaryotic elongation factors.-Function:The factor EF-G catalyzes the translocation of the tRNA and mRNA down the ribosome at the end of each round of polypeptide elongation. Homologous to EF-Tu + tRNA, EF-G also binds to the ribosome in its GTP-bound...
, catalyzing the translocationTranslocationTranslocation may refer to:* Chromosomal translocation, in genetics* Translocation in plants, transport of food or pesticides through phloem or xylem* Protein translocation or protein targeting, a process in protein biosynthesis...
of the tRNA and mRNA down the ribosome at the end of each round of polypeptide elongation.
External links
- nobelprize.org Explaining the function of eukaryotic elongation factors