Molecular basis of messenger RNA recognition by the specific bacterial repressing clamp RsmA/CsrA.
Proteins of the RsmA/CsrA family are global translational regulators in many bacterial species. We have determined the solution structure of a complex formed between the RsmE protein, a member of this family from Pseudomonas fluorescens, and a target RNA encompassing the ribosome-binding site of the hcnA gene. The RsmE homodimer with its two RNA-binding sites makes optimal contact with an 5'-A/UCANGGANGU/A-3' sequence in the mRNA. When tightly gripped by RsmE, the ANGGAN core folds into a loop, favoring the formation of a 3-base-pair stem by flanking nucleotides. We validated these findings by in vivo and in vitro mutational analyses. The structure of the complex explains well how, by sequestering the Shine-Dalgarno sequence, the RsmA/CsrA proteins repress translation.
Schubert
Mario
M
Institute of Molecular Biology and Biophysics, ETH Zürich, CH-8093 Zürich, Switzerland.
Lapouge
Karine
K
Duss
Olivier
O
Oberstrass
Florian C
FC
Jelesarov
Ilian
I
Haas
Dieter
D
Allain
Frédéric H-T
FH
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*; D024202:Electrophoretic Mobility Shift Assay; D008958:Models, Molecular; D008969:Molecular Sequence Data; D019906:Nuclear Magnetic Resonance, Biomolecular; D011550:Pseudomonas aeruginosa / Q000378:metabolism*; D012329:RNA, Bacterial / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000378:metabolism / Q000502:physiology*
D001426:Bacterial Proteins; D012329:RNA, Bacterial; D012333:RNA, Messenger; D016601:RNA-Binding Proteins