Macromolecular Complexes in Live Cells
Program: Cell Biology
Group Leader: Maïté COPPEY
Tel.: +33 (0)157278041coppey.maite@ijm.univ-paris-diderot.fr
Floor 3
A cell's shape can be linked to its function, and is dynamically regulated both by the cell's activity and by environmental cues. The involvement of the extracellular matrix in the regulation of cell behavior, polarity and fate is essential, due to such mechanical properties as its rigidity, for example. Rigidity is known to play a role in the activity of molecular switches and the dynamic reorganisation of the cytoskeleton, events that take place after the activation of integrin receptors. In turn, internal forces are generated by the dynamic behavior of the cytoskeleton (actin and microtubules) and molecular motors, and this sustains changes in cell shape and related localized activities. In the same way that cells sense chemical gradients, they can sense rigidity gradients (durotaxis).
We are interested in finding an answer to two basic questions : (1) what is the relationship between the physical properties (amplitude, gradients, geometry) of extracellular mechanical tensions (and rigidity) and the intracellular biological response, and (2) what are the underlying molecular and physical mechanisms that sustain cell polarity (subcellular asymmetries relying on the differential and dynamic balance of regionalization of the processes)?
We are currently developing methods based on the measurement of macromolecular interactions by fluorescence microscopy combined with nanomanipulation of individual cells to determine the effect of the mechanical properties of the extracellular matrix on the dynamic behaviour of subcellular complexes and on change in cell shape.
Actin dynamics and microtubule polymerisation can be monitored simultaneously in a living neuronal cell during polarization. (Isabelle Vallois and Christiane Durieux)
Actin in red (mcherry-actin) and EB1 (for microtubules tips ) in green (GFP-EB1). (We thank R. Tsien for mcherry plasmid and Mimori Kiyosue for GFP-EB1 plasmid)
Selection of Publications
Live-Cell Imaging Reveals Multiple Interactions between Epstein-Barr Virus Nuclear Antigen 1 and Cellular Chromatin during Interphase and Mitosis.
Jourdan N, Jobart-Malfait A, Dos Reis G, Quignon F, Piolot T, Klein C, Tramier M, Coppey-Moisan M, Marechal V.
J Virol. 2012 May;86(9):5314-29. Epub 2012 Feb 15.
Abstract
Dual-color fluorescence lifetime correlation spectroscopy to quantify protein-protein interactions in live cell.
Padilla-Parra S, Audugé N, Coppey-Moisan M, Tramier M.
Microsc Res Tech. 2011 Aug;74(8):788-93. Epub 2011 May 26.
Abstract
Spatiotemporal analysis of cell response to a rigidity gradient: a quantitative study using multiple optical tweezers.
Allioux-Guérin M, Icard-Arcizet D, Durieux C, Hénon S, Gallet F, Mevel JC, Masse MJ, Tramier M, Coppey-Moisan M.
Biophys J. 2009 Jan;96(1):238-47.
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Dynamic interaction of amphiphysin with N-WASP regulates actin assembly.
Yamada H, Padilla-Parra S, Park SJ, Itoh T, Chaineau M, Monaldi I, Cremona O, Benfenati F, De Camilli P, Coppey-Moisan M, Tramier M, Galli T, Takei K.
J Biol Chem. 2009 Dec 4;284(49):34244-56. Epub 2009 Sep 16.
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Quantitative FRET analysis by fast acquisition time domain FLIM at high spatial resolution in living cells.
Padilla-Parra S, Audugé N, Coppey-Moisan M, Tramier M.
Biophys J. 2008 Sep 15;95(6):2976-88. Epub 2008 Jun 6.
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Last modified 04/23/2012