We suggest a new non-invasive method, based on applying of optical trapping for viscoelastic properties investigation of cellular supramolecular complexes (chromatin, nucleolus). As a model object, we used mice oocytes because of their well-known biochemistry, intracellular organization and large size of nuclei (10 μm). Nucleoli were supposed to be natural microspheres, so it was possible to catch them by optical tweezers and create deformations of nuclei matter. Based on our data, measured relaxation time of nucleoli could be an indicator of spatial viscoelastic properties changes. Also, optical trapping is a powerful tool for visualization of interactions between nucleus and cytoplasm.
optical trapping, mouse oocyte, microrheology, soft matter, nucleolus, biopolymers
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