spatiotemporally-controlled-nuclear-translocation-guests-living-cells

Spatiotemporally Controlled Nuclear Translocation of Guests in Living Cells Using Caged Molecular Glues as Photoactivatable Tags

The cell nucleus is one of the most important organelles as a subcellular drug-delivery target, since modulation of gene replication and expression is ...

University of Tokyo

PGlue(PZ), a pyrazoline (PZ)-based fluorescent adhesive which can be generated spatiotemporally in living systems, was developed. Since PGlue(PZ) carries many guanidinium ion (Gu(+)) pendants, it strongly adheres to various oxyanionic substrates through a multivalent salt-bridge interaction. PGlue(PZ) is given by bioorthogonal photopolymerization of a Gu(+)-appended monomer (Glue(TZ)), bearing tetrazole (TZ) and olefinic termini. Upon exposure to UV light, Glue(TZ) transforms into a nitrileimine (NI) intermediate (Glue(NI)), which is eligible for 1,3-dipolar polycycloaddition. However, Glue(NI) in aqueous media can concomitantly be deactivated into Glue(WA) by the addition of water, and the polymerization hardly occurs unless Glue(NI) is concentrated. We found that, even under high dilution, Glue(NI) is concentrated on oxyanionic substrates to a sufficient level for the polymerization, so that their surfaces can be point-specifically functionalized with PGlue(PZ) by the use of a focused beam of UV light.

Photoinduced Bioorthogonal 1,3-Dipolar Poly-cycloaddition Promoted by Oxyanionic Substrates for Spatiotemporal Operation of Molecular Glues.

Water-soluble bioadhesive polymers bearing multiple guanidinium ion (Gu) pendants at their side-chain termini (Glue  -BA,  = 10 and 29) that were conjugated with benzamidine (BA) as a trypsin inhibitor were developed. The Glue  -BA molecules are supposed to adhere to oxyanionic regions of the trypsin surface, even in buffer,  a multivalent Gu/oxyanion salt-bridge interaction, such that their BA group properly blocks the substrate-binding site. In fact, Glue-BA and Glue-BA exhibited 35- and 200-fold higher affinities for trypsin, respectively, than a BA derivative without the glue moiety (TEG-BA). Most importantly, Glue-BA inhibited the protease activity of trypsin 13-fold more than TEG-BA. In sharp contrast,  Glue-BA, which bears 27 Gu units along the main chain and has a 5-fold higher affinity than TEG-BA for trypsin, was inferior even to TEG-BA for trypsin inhibition.

Molecular glues for manipulating enzymes: trypsin inhibition by benzamidine-conjugated molecular glues.

Molecular adhesion based on multivalent interactions plays essential roles in various biological processes. Hence, "molecular glues" that can adhere to biomolecules may modulate biomolecular functions and therefore can be applied to therapeutics. This tutorial review describes design strategies for developing adhesive motifs for biomolecules based on multivalent interactions. We highlight a guanidinium ion-based salt-bridge as a key interaction for adhesion to biomolecules and discuss the application of molecular glues for manipulation of biomolecular assemblies, drug delivery systems, and modulation of biomolecular functions.

Article	Year
Photoinduced Bioorthogonal 1,3-Dipolar Poly-cycloaddition Promoted by Oxyanionic Substrates for Spatiotemporal Operation of Molecular Glues. Angewandte Chemie (International ed. in English)\| PubMed ID: 26530322	2016
Molecular glues for manipulating enzymes: trypsin inhibition by benzamidine-conjugated molecular glues. Chemical science\| PubMed ID: 28706668	2015
Guanidinium-based "molecular glues" for modulation of biomolecular functions. Chemical Society reviews\| PubMed ID: 29034942	2017

Kou Okuro

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