Versatile laser‐based cell manipulator

Abstract

Here we describe a two-photon microscope and laser ablation setup combined with optical tweezers. We tested the setup on the fission yeast Schizosaccharomyces pombe, a commonly used model organism. We show that long-term imaging can be achieved without significant photo-bleaching or damage of the sample. The setup can precisely ablate sub-micrometer structures, such as microtubules and mitotic spindles, inside living cells, which remain viable after the manipulation. Longer exposure times lead to ablation, while shorter exposures lead to photo-bleaching of the target structure. We used optical tweezers to trap intracellular particles and to displace the cell nucleus. Two-photon fluorescence imaging of the manipulated cell can be performed simultaneously with trapping. The combination of techniques described here may help to solve a variety of problems in cell biology, such as positioning of organelles and the forces exerted by the cytoskeleton.

Microtubules and motor proteins: Mechanically regulated self-organization in vivo

“…In contrast, if the SPB movement is driven mainly by pushing, then the ablation will have an opposite effect. Using laser ablation of specific microtubules [23,25,26], we perturbed the force balance in the cell to directly test the contribution of pulling and pushing. Our experiments showed that after selective ablation of the leading MTs, the SPB rapidly changed the direction of its motion (Fig.…”

Surface-modified complex SU-8 microstructures for indirect optical manipulation of single cells

“…OT can directly manipulate cell organelles [14], study the elasticity of cell interior [15] or manipulate and image even entire cells [16,17]. Indirect manipulation becomes necessary, for instance, in case of biological macromolecules which themselves cannot be trapped.…”

A voyage from the nano world to the macro through the micro

“…In this respect the work of Rossi et al [15] shows how the use of lasers can be useful not only for imaging, but also for some welding operation. Conversely to the nanodisruption use of laser in [11], they show how lasers can be used to reconstruct macroscopic structures. In particular, laser welding of ocular tissues was demonstrated as a technique alternative or adjunct to conventional suturing in ophthalmic surgery.…”

“…A further step can be added to the observations in living cells [11] introducing an interactive way of operation based on nanosurgery, which is able to investigate some basic problems in cell biology, such as positioning of organelles and the forces exerted by the cytoskeleton. In this case the cell is interrogated by means of a perturbation, a disruption of a subcellular structure, and the response furnish information about the process under investigation.…”