description
The translation elongation cycle adds one amino acid at a time to a growing polypeptide according to the sequence of codons found in the mRNA. The next available codon on the mRNA is exposed in the aminoacyl-tRNA (aa-tRNA) binding site (A site) on the 30S subunit.A: Ternary complexes of aa -tRNA:eEF1A:GTP enter the ribosome and enable the anticodon of the tRNA to make a codon/anticodon interaction with the A-site codon of the mRNA. B: Upon cognate recognition, the eEF1A:GTP is brought into the GTPase activating center of the ribosome, GTP is hydrolyzed and eEF1A:GDP leaves the ribosome. C: The peptidyl transferase center of ribosome catalyses the formation of a peptide bond between the incoming amino acid and the peptide found in the peptidyl-tRNA binding site (P site). D: In the pre-translocation state of the ribosome, the eEF2:GTP enters the ribosome, physically translocating the peptidyl-tRNA out of the A site to P site and leaves the ribosome eEF2:GDP. This action of eEF2:GTP accounts for the precise movement of the mRNA by 3 nucleotides.Consequently, deacylated tRNA is shifted to the E site. A ribosome associated ATPase activity is proposed to stimulate the release of deacylated tRNA from the E site subsequent to translocation (Elskaya et al., 1991). In this post-translocation state, the ribosome is now ready to receive a new ternary complex.This process is illustrated below with: an amino acyl-tRNA with an amino acid, a peptidyl-tRNA with a growing peptide, a deacylated tRNA with an -OH, and a ribosome with A,P and E sites to accommodate these three forms of tRNA
external resources
NCBI:1268690
REACTOME:R-HSA-156842
PUBMED:15189156
genes
EEF1A1
,
EEF1A2
,
EEF1B2
,
EEF1D
,
EEF1G
,
EEF2
,
FAU
,
RPSA
,
RPL10A
,
RPL3
,
RPL3L
,
RPL4
,
RPL5
,
RPL6
,
RPL7
,
RPL7A
,
RPL8
,
RPL9
,
RPL10
,
RPL11
,
RPL12
,
RPL13
,
RPL15
,
RPL17
,
RPL18
,
RPL18A
,
RPL19
,
RPL21
,
RPL22
,
RPL23A
,
RPL24
,
RPL26
,
RPL27
,
RPL30
,
RPL27A
,
RPL28
,
RPL29
,
RPL31
,
RPL32
,
RPL34
,
RPL35A
,
RPL36AL
,
RPL37
,
RPL37A
,
RPL38
,
RPL39
,
RPL41
,
RPL36A
,
RPLP0
,
RPLP1
,
RPLP2
,
RPS2
,
RPS3
,
RPS3A
,
RPS4X
,
RPS4Y1
,
RPS5
,
RPS6
,
RPS7
,
RPS8
,
RPS9
,
RPS10
,
RPS11
,
RPS12
,
RPS13
,
RPS14
,
RPS15
,
RPS15A
,
RPS16
,
RPS17
,
RPS18
,
RPS19
,
RPS20
,
RPS21
,
RPS23
,
RPS24
,
RPS25
,
RPS26
,
RPS27
,
RPS27A
,
RPS28
,
RPS29
,
UBA52
,
RPL14
,
RPL23
,
RPL35
,
RPL13A
,
RPL36
,
RPS27L
,
RPL26L1
,
RPL39L
,
RPS4Y2
,
RPL10L
,
EEF1A1P5
,
RPL22L1
,