TY - JOUR
T1 - Membrane association of the bacterial riboregulator Hfq and functional perspectives
AU - Malabirade, Antoine
AU - Morgado-Brajones, Javier
AU - Trépout, Sylvain
AU - Wien, Frank
AU - Marquez, Ileana
AU - Seguin, Jérôme
AU - Marco, Sergio
AU - Velez, Marisela
AU - Véronique, Arluison
N1 - Funding Information:
We would like to thank PICT-Ibisa for providing access to JEOL 2200FS TEM. SRCD measurements on DISCO beamline at the SOLEIL Synchrotron were performed under proposal #20161398. This work was supported by CNRS and CEA (VA), Université Paris Saclay (AM). We gratefully acknowledge help to MV from the French Embassy for their program for scientific and university cooperation. We are indebted to F. Gobeaux (CEA Saclay, Gif-sur-Yvette, France), Liliane Mouawad (Institut Curie, Orsay, France), Marc Lemaire and Jose-Luis Vasquez-Ibar for many fruitful discussions and to Jean-Pierre Lecaer (ICSN, CNRS, Gif-sur-Yvette, France) for mass spectrometry analysis. We thank Kimberly Stanek (University of Virginia) for her careful and critical reading of our manuscript.
Publisher Copyright:
© 2017 The Author(s).
PY - 2017/9/6
Y1 - 2017/9/6
N2 - Hfq is a bacterial RNA binding protein that carries out several roles in genetic expression regulation, mainly at the post-transcriptional level. Previous studies have shown its importance in growth and virulence of bacteria. Here, we provide the direct observation of its ability to interact with membranes. This was established by co-sedimentation assay, cryo-transmission electron (cryo-TEM) and atomic force (AFM) microscopies. Furthermore, our results suggest a role for its C-terminus amyloidogenic domain in membrane disruption. Precisely, AFM images of lipid bilayers in contact with Hfq C-terminus fibrils show the emergence of holes with a size dependent on the time of interaction. Cryo-TEM observations also show that liposomes are in contact with clusters of fibrils, with occasional deformation of the vesicles and afterward the apparition of a multitude of tiny vesicles in the proximity of the fibrils, suggesting peptide-induced breakage of the liposomes. Finally, circular dichroism spectroscopy demonstrated a change in the secondary structure of Hfq C-terminus upon interaction with liposomes. Altogether, these results show an unexpected property of Hfq and suggest a possible new role for the protein, exporting sRNA outside of the bacterial cell.
AB - Hfq is a bacterial RNA binding protein that carries out several roles in genetic expression regulation, mainly at the post-transcriptional level. Previous studies have shown its importance in growth and virulence of bacteria. Here, we provide the direct observation of its ability to interact with membranes. This was established by co-sedimentation assay, cryo-transmission electron (cryo-TEM) and atomic force (AFM) microscopies. Furthermore, our results suggest a role for its C-terminus amyloidogenic domain in membrane disruption. Precisely, AFM images of lipid bilayers in contact with Hfq C-terminus fibrils show the emergence of holes with a size dependent on the time of interaction. Cryo-TEM observations also show that liposomes are in contact with clusters of fibrils, with occasional deformation of the vesicles and afterward the apparition of a multitude of tiny vesicles in the proximity of the fibrils, suggesting peptide-induced breakage of the liposomes. Finally, circular dichroism spectroscopy demonstrated a change in the secondary structure of Hfq C-terminus upon interaction with liposomes. Altogether, these results show an unexpected property of Hfq and suggest a possible new role for the protein, exporting sRNA outside of the bacterial cell.
UR - http://www.scopus.com/inward/record.url?scp=85028933084&partnerID=8YFLogxK
U2 - 10.1038/s41598-017-11157-5
DO - 10.1038/s41598-017-11157-5
M3 - Article
C2 - 28878270
AN - SCOPUS:85028933084
SN - 2045-2322
VL - 7
JO - Scientific Reports
JF - Scientific Reports
IS - 1
M1 - 10724
ER -