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Self-propelled molecular entities enable studying swarm behavior on a macroscopic scale but programmability of interactions has yet not been achieved. Here the authors show reversible regulation of DNA-functionalized microtubules by DNA signals and switching between solitary and swarm behaviour by employing photoresponsive DNA strands.

It is challenging to characterize the mechanical properties of soft surfaces owing to the coupling between surface deformation and elasticity of bulk materials. Here, Inoue et al. use motile cytoskeletal filaments as active probes, whose direction reflects the stress field experienced by the surface.

Dual chemo- and thermo-responsive phase separations of poly(4-hydroxystyrene) in non-aqueous media were demonstrated. The addition of small amounts of hydrogen-bonding molecules as chemical stimuli caused a considerable change of LCST-type thermo-responsiveness of poly(4-hydroxystyrene) in 1,4-dioxane/toluene. Secondary amines or molecules containing two hydrogen-bonding functional groups could cross-link the polymer chains through the hydrogen bonds, which altered the solvation state and induced the UCST-type thermo-responsiveness or insolubility of the polymer. This dual stimuli-responsive system worked as a chemical sensor to detect the presence of acids.

We demonstrated biomolecular motors driven swarming of microtubules and their dissociation under UV and visible light irradiation, respectively. A photoresponsive molecule, para tert-butyl-substituted azobenzene was incorporated to the backbone of single strand DNA, which functions as a photoswitch to control the swarming of microtubules in a reversible manner. This work is expected to expand the potential applications of biomolecular motors in developing photoregulated molecular machines.

Stabilization of microtubules occurs by paclitaxel bound to the taxoid site and cevipabulin (and its derivative) bound to the taxoid site and/or vinca alkaloid domain of the β-tubulin in tubulin heterodimer.

The graphical abstract shows that the kinesin-driven quantum dot transport along microtubule immobilized on a substrate using glutaraldehyde concentration ≤0.10% (v/v) remain unaltered, whereas, at higher glutaraldehyde concentration, >0.10% (v/v), the quantum dot transportation is slowed down.

Rotating ring-shaped microtubule assemblies were successfully formed on dynein-coated surface through active self-organization process in a similar way to kinesin. However, no preferential direction of rotation was observed in contrast to the aforementioned results of previous kinesin studies. This indicates that dynein is less sensitive to the experimental condition than kinesin.

We have successfully developed a system to perform active self-organization of microtubules (MT) using a streptavidin–biotin interaction in a nitrogen atmosphere (inert chamber). Use of inert chamber dramatically improved the lifetime of assembled microtubules and kept them active for a longer period of time compared to the case without using inert chamber. Longer lifetime of assembled microtubules obtained using the inert chamber would be significantly important in further development of biomolecular motor protein-based organized systems.

An unidirectionally deformable material with reversibility was achieved. The method relies on crystal crosslinking of pillared-layer metal–organic framework (PLMOF), followed by exchange of the pillar ligand to monotopic ligand. The obtained crosslinked MOF crystal exhibited reversibly unidirectional compression and expansion upon cycles of drying and immersion in good solvents. The preservation of layer structure enabled to confirm the unidirectional deformation not only macroscopically but also microscopically. Our strategy will be a promising general method for construction of anisotropic deforming materials, which can be often seen in biological systems or mechanical devices.

A new type of porous crystal, metal–organic framework (MOF), has been recently utilized for the preparation of network polymers. The obtained network polymers possess highly controlled structures derived from the molecular organization of MOF crystal. This focus review emphasizes the significance of integration of flexible organic polymers and rigid MOFs to attain shaped network polymers and organic–inorganic hybrid networks.

Microtubules (MTs) consisting of tubulins are important targets of drugs for MT-related diseases. We have previously designed a linear Tau-derived peptide (TP) that binds to the interior of MTs. In this article, a cyclic TP (TCP) was developed for enhanced binding to tubulin and stabilization of MTs. The fluorescently labeled TCP exhibited a remarkably enhanced binding affinity to tubulin compared to the linear TP. The stabilization of MTs by binding of TCP was demonstrated, such as formation of typically unstable MTs in the presence of guanosine triphosphate.

This review focuses on our novel approaches for developing functional polymers by dissociation phenomena of macromolecular complexes. One is highly swellable polymer gels, superabsorbent polymers for nonpolar organic solvents, and the other is thermo-responsive polymers at ambient temperature in nonpolar solvents. Both of them are well-known in water, but no design has ever been proposed for other media. The dissociation of the macromolecular complexes plays a key role for them. Therefore, controlling the dissociation processes in supramolecular chemistry should be another important strategy for emerged dynamic functions.