Figure: the hair bundle protruding from the surface of a mechanosensory hair cell from the inner ear of the bullfrog (source: P. Gillespie, OHSU, Portland, USA)
Deadline for application: March 1st, 2017
Duration: 24 months
Where: Institut Curie, Paris, France
Keywords: hair cell, mechanosensitivity, hearing, actin, biophysics
Director and team
Advisor: Pascal Martin.
Research team: Active Mechano-Sensitivity by Hair Cells in the Inner Ear
Research department: UMR 168 - Physical Chemistry
Our group studies mechano-sensitivity by the cellular microphones of the inner ear ‒the hair cells. Each hair cell is endowed with a beautiful tuft of elongated microvilli ‒the hair bundle‒ that works both as receptor antenna and mechanical amplifier for sound detection by the cell (see Figure). To shed light on this active sensory process, we are developing mechanical, electrophysiological and theoretical approaches to probe the biophysical properties of single cells. We propose to work on the biophysical mechanisms that tune each hair cell to a characteristic frequency of sound-evoked vibration. In particular, we wish to elucidate the role played by mechanical tension in tip links that interconnect neighboring stereocilia within the hair bundle on the bundle size and characteristic frequency.
International, interdisciplinary & intersectoral aspects of the project
The project involves international collaborations with a Korean group (Prof Jinwoo Cheon, Yonsei University) for the development of magnetic nanoparticles to apply forces to the hair bundle and with Oticon Medical, an industrial partner located in Denmark that develops hearing aids and cochlear implants. The work will be done through a collaboration between our group (hair-cell biophysics), and that of Prof Christine petit (Institut Pasteur; hair-cell genetics and physiology), which ensures the interdisciplinary expertise between physics and biology that will be necessary for the success of the project.
- Bormuth V, Barral J, Joanny JF, Jülicher F, Martin P.
Transduction channels’gating can control friction on vibrating hair-cell bundles in the ear.
Proc Natl Acad Sci U S A. 2014 May 20;111(20):7185-90. doi: 10.1073/pnas.1402556111.
- Barral J, Martin P.
Phantom tones and suppressive masking by active nonlinear oscillation of the hair-cell bundle. Proc Natl Acad Sci U S A. 2012 May 22;109(21):E1344-51. doi: 10.1073/pnas.1202426109.
- Barral J, Dierkes K, Lindner B, Jülicher F, Martin P.
Coupling a sensory hair-cell bundle to cyber clones enhances nonlinear amplification.
Proc Natl Acad Sci U S A. 2010 May 4;107(18):8079-84. doi: 10.1073/pnas.0913657107.
- Hudspeth AJ, Jülicher F, Martin P.
A critique of the critical cochlea: Hopf, a bifurcation, is better than none.
J Neurophysiol. 2010 Sep;104(3):1219-29. doi: 10.1152/jn.00437.2010.
- Tinevez J-Y, Jülicher F, Martin P.
Unifying the various incarnations of active hair-bundle motility by the vertebrate hair cell.
Biophys J. 2007 Dec 1;93(11):4053-67.
Expected profile of the candidate
Applicants should have a strong desire to work at the interface between physics and biology on living cells, and should show solid capacity for independent, quantitative and creative thinking. Background in biophysics is strongly recommended. Both experimental physicists and biologists dedicated to quantitative approaches are welcome. Background in cell or biomolecule mechanics, the cytoskeleton, sensory systems (electrophysiology), or mechanobiology is a plus but not compulsory. The project highly relies on microscopy and micromanipulation of cells, for which the applicant should have either experience or a strong motivation to learn.
The Institut Curie offers a highly collaborative, interdisciplinary, and creative environment. The department Physico-Chimie Curie is internationally recognized as a premiere center for physical approaches of biological problems. It is conveniently located at the heart of the Latin Quarter, in central Paris.
If interested, please send a short letter describing your motivations and past achievements, a curriculum vitae, and two letters of reference.