Movement of the decoding region of the 16 S ribosomal RNA accompanies tRNA translocation.
The ribosome undergoes pronounced periodic conformational changes during protein synthesis. Of particular importance are those occurring around the decoding site, the region of the 16 S rRNA interacting with the mRNA-(tRNA)(2) complex. We have incorporated structural information from X-ray crystallography and nuclear magnetic resonance into cryo-electron microscopic maps of ribosomal complexes designed to capture structural changes at the translocation step of the polypeptide elongation cycle. The A-site region of the decoding site actively participates in the translocation of the tRNA from the A to the P-site upon GTP hydrolysis by elongation factor G, shifting approximately 8 A toward the P-site. This implies that elongation factor G actively pushes both the decoding site and the mRNA/tRNA complex during translocation.
VanLoock
M S
MS
Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294-0005, USA.
Agrawal
R K
RK
Gabashvili
I S
IS
Qi
L
L
Frank
J
J
Harvey
S C
SC
D001483:Base Sequence; D001665:Binding Sites; D020285:Cryoelectron Microscopy; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000737:chemistry / Q000235:genetics*; D006153:Guanosine Diphosphate / Q000378:metabolism; D006160:Guanosine Triphosphate / Q000031:analogs & derivatives* / Q000378:metabolism; D006868:Hydrolysis; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular; D009690:Nucleic Acid Conformation; D010441:Peptide Chain Elongation, Translational; D020653:Peptide Elongation Factor G / Q000378:metabolism; D011487:Protein Conformation; D012336:RNA, Ribosomal, 16S / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D012343:RNA, Transfer / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D012270:Ribosomes / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*
D020653:Peptide Elongation Factor G; D012336:RNA, Ribosomal, 16S; D006153:Guanosine Diphosphate; C004805:5'-guanylylmethylenebisphosphonate; D006160:Guanosine Triphosphate; D012343:RNA, Transfer