RF3 induces ribosomal conformational changes responsible for dissociation of class I release factors.
During translation termination, class II release factor RF3 binds to the ribosome to promote rapid dissociation of a class I release factor (RF) in a GTP-dependent manner. We present the crystal structure of E. coli RF3*GDP, which has a three-domain architecture strikingly similar to the structure of EF-Tu*GTP. Biochemical data on RF3 mutants show that a surface region involving domains II and III is important for distinct steps in the action cycle of RF3. Furthermore, we present a cryo-electron microscopy (cryo-EM) structure of the posttermination ribosome bound with RF3 in the GTP form. Our data show that RF3*GTP binding induces large conformational changes in the ribosome, which break the interactions of the class I RF with both the decoding center and the GTPase-associated center of the ribosome, apparently leading to the release of the class I RF.
Gao
Haixiao
H
Howard Hughes Medical Institute, Health Research, Inc. at the Wadsworth Center, Empire State Plaza, Albany, NY 12201-0509, USA.
Zhou
Zhihong
Z
Rawat
Urmila
U
Huang
Chenhui
C
Bouakaz
Lamine
L
Wang
Chernhoe
C
Cheng
Zhihong
Z
Liu
Yuying
Y
Zavialov
Andrey
A
Gursky
Richard
R
Sanyal
Suparna
S
Ehrenberg
Måns
M
Frank
Joachim
J
Song
Haiwei
H
D001665:Binding Sites; D020285:Cryoelectron Microscopy; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000737:chemistry* / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D006153:Guanosine Diphosphate / Q000737:chemistry / Q000378:metabolism; D006160:Guanosine Triphosphate / Q000737:chemistry / Q000378:metabolism; D015394:Molecular Structure; D009154:Mutation; D010444:Peptide Elongation Factor Tu / Q000737:chemistry / Q000378:metabolism; D010454:Peptide Termination Factors / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D017434:Protein Structure, Tertiary; D012270:Ribosomes / Q000737:chemistry* / Q000378:metabolism
D029968:Escherichia coli Proteins; D010454:Peptide Termination Factors; C489007:prfC protein, E coli; D006153:Guanosine Diphosphate; D006160:Guanosine Triphosphate; D010444:Peptide Elongation Factor Tu