The degree of macromolecular crowding in the cytoplasm and nucleoplasm of mammalian cells is conserved

Macromolecular crowding provides the cytoplasm and the nucleoplasm with strongly viscoelastic properties and renders the diffusion of soluble proteins in both fluids anomalous. Here, we have determined the nanoscale viscoelasticity of the cytoplasm and the nucleoplasm in different mammalian cell lines. In contrast to the cell‐specific response on the macroscale the nanoscale viscoelasticity (i.e. the behavior on length scales about 100‐fold smaller than the cell size) only showed minor variations between different cell types. Similarly, the associated anomalous diffusion properties varied only slightly. Our results indicate a conserved state of macromolecular crowding in both compartments for a variety of mammalian cells with the cytoplasm being somewhat more crowded than the nucleus.

[1]  Mason,et al.  Optical measurements of frequency-dependent linear viscoelastic moduli of complex fluids. , 1995, Physical review letters.

[2]  G. Schreiber,et al.  Effect of crowding on protein-protein association rates: fundamental differences between low and high mass crowding agents. , 2004, Journal of molecular biology.

[3]  Farshid Guilak,et al.  A thin-layer model for viscoelastic, stress-relaxation testing of cells using atomic force microscopy: do cell properties reflect metastatic potential? , 2007, Biophysical journal.

[4]  Z. Stachura,et al.  Elasticity of normal and cancerous human bladder cells studied by scanning force microscopy , 1999, European Biophysics Journal.

[5]  Stefan Schinkinger,et al.  Optical deformability as an inherent cell marker for testing malignant transformation and metastatic competence. , 2005, Biophysical journal.

[6]  A. Rowat,et al.  Characterization of the elastic properties of the nuclear envelope , 2005, Journal of The Royal Society Interface.

[7]  M. Saxton,et al.  Lateral diffusion in an archipelago. Single-particle diffusion. , 1993, Biophysical journal.

[8]  D A Weitz,et al.  Microrheology of entangled F-actin solutions. , 2003, Physical review letters.

[9]  J. Nickerson,et al.  Experimental observations of a nuclear matrix. , 2001, Journal of cell science.

[10]  A. Verkman.  Solute and macromolecule diffusion in cellular aqueous compartments. , 2002, Trends in biochemical sciences.

[11]  M. Weiss,et al.  In a mirror dimly: tracing the movements of molecules in living cells. , 2004, Trends in cell biology.

[12]  S. Taniguchi,et al.  [Cytoskeleton of cancer cells]. , 1986, Nihon rinsho. Japanese journal of clinical medicine.

[13]  E. Schutter,et al.  Anomalous Diffusion in Purkinje Cell Dendrites Caused by Spines , 2006, Neuron.

[14]  K. Luby-Phelps,et al.  Cytoarchitecture and physical properties of cytoplasm: volume, viscosity, diffusion, intracellular surface area. , 2000, International review of cytology.

[15]  Tommy Nilsson,et al.  Spatiotemporal dynamics of the COPI vesicle machinery , 2003, EMBO reports.

[16]  M. Saxton.  A biological interpretation of transient anomalous subdiffusion. II. Reaction kinetics. , 2008, Biophysical journal.

[17]  O. Thoumine,et al.  Comparison of the mechanical properties of normal and transformed fibroblasts. , 1997, Biorheology.

[18]  S. Zimmer,et al.  Viscoelastic properties of transformed cells: role in tumor cell progression and metastasis formation. , 1991, Biorheology.

[19]  Daniel S. Banks,et al.  Anomalous diffusion of proteins due to molecular crowding. , 2005, Biophysical journal.

[20]  M. Weiss,et al.  Probing the nanoscale viscoelasticity of intracellular fluids in living cells. , 2007, Biophysical journal.

[21]  A. Bausch,et al.  Viscoelasticity of isotropically cross-linked actin networks. , 2007, Physical review letters.

[22]  Ashkan Vaziri,et al.  Mechanics and deformation of the nucleus in micropipette aspiration experiment. , 2007, Journal of biomechanics.

[23]  Yiider Tseng,et al.  Micromechanical mapping of live cells by multiple-particle-tracking microrheology. , 2002, Biophysical journal.

[24]  M. Saxton,et al.  Lateral diffusion in an archipelago. Dependence on tracer size. , 1993, Biophysical journal.

[25]  M. Weiss,et al.  Anomalous subdiffusion is a measure for cytoplasmic crowding in living cells. , 2004, Biophysical journal.

[26]  Michael J Saxton,et al.  A biological interpretation of transient anomalous subdiffusion. I. Qualitative model. , 2007, Biophysical journal.

[27]  Allen P. Minton,et al.  Cell biology: Join the crowd , 2003, Nature.

[28]  J. Segall,et al.  A critical step in metastasis: in vivo analysis of intravasation at the primary tumor. , 2000, Cancer research.

[29]  Yiider Tseng,et al.  Micro-organization and visco-elasticity of the interphase nucleus revealed by particle nanotracking , 2004, Journal of Cell Science.

[30]  E. Elson,et al.  Fluorescence Correlation Spectroscopy Measures Molecular Transport in Cells , 2001, Traffic.