Publication Date:
2014-05-16
Description:
MicroRNA and protein sequestration by non-coding RNAs (ncRNAs) has recently generated much interest. In the bacterial Csr/Rsm system, which is considered to be the most general global post-transcriptional regulatory system responsible for bacterial virulence, ncRNAs such as CsrB or RsmZ activate translation initiation by sequestering homodimeric CsrA-type proteins from the ribosome-binding site of a subset of messenger RNAs. However, the mechanism of ncRNA-mediated protein sequestration is not understood at the molecular level. Here we show for Pseudomonas fluorescens that RsmE protein dimers assemble sequentially, specifically and cooperatively onto the ncRNA RsmZ within a narrow affinity range. This assembly yields two different native ribonucleoprotein structures. Using a powerful combination of nuclear magnetic resonance and electron paramagnetic resonance spectroscopy we elucidate these 70-kilodalton solution structures, thereby revealing the molecular mechanism of the sequestration process and how RsmE binding protects the ncRNA from RNase E degradation. Overall, our findings suggest that RsmZ is well-tuned to sequester, store and release RsmE and therefore can be viewed as an ideal protein 'sponge'.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Duss, Olivier -- Michel, Erich -- Yulikov, Maxim -- Schubert, Mario -- Jeschke, Gunnar -- Allain, Frederic H-T -- England -- Nature. 2014 May 29;509(7502):588-92. doi: 10.1038/nature13271. Epub 2014 May 14.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Institute of Molecular Biology and Biophysics, ETH Zurich, CH-8093 Zurich, Switzerland. ; Laboratory of Physical Chemistry, ETH Zurich, CH-8093 Zurich, Switzerland.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/24828038" target="_blank"〉PubMed〈/a〉
Keywords:
Animals
;
Base Sequence
;
Electron Spin Resonance Spectroscopy
;
Escherichia coli/chemistry/genetics/metabolism
;
Escherichia coli Proteins/chemistry/*metabolism
;
Methyltransferases/chemistry/*metabolism
;
Models, Biological
;
Models, Molecular
;
Molecular Weight
;
Nuclear Magnetic Resonance, Biomolecular
;
Nucleic Acid Conformation
;
*Protein Binding
;
Protein Multimerization
;
RNA, Untranslated/chemistry/genetics/*metabolism
;
Ribonucleases/metabolism
;
Ribonucleoproteins/chemistry/genetics/metabolism
Print ISSN:
0028-0836
Electronic ISSN:
1476-4687
Topics:
Biology
,
Chemistry and Pharmacology
,
Medicine
,
Natural Sciences in General
,
Physics
