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Synthetic hydrogel mimics of the nuclear pore complex for the study of nucleocytoplasmic transport defects in C9orf72 ALS/FTD

Abstract

Dipeptide repeats (DPRs) associated with C9orf72 repeat expansions perturb nucleocytoplasmic transport and are implicated in the pathogenesis of amyotrophic lateral sclerosis. We present a synthetic hydrogel platform that can be used to analyze aspects of the molecular interaction of dipeptide repeats and the phenylalanine-glycine (FG) phase of the nuclear pore complex (NPC). Hydrogel scaffolds composed of acrylamide and copolymerized with FG monomers are first formed to recapitulate key FG interactions found in the NPC. With labeled probes, we find evidence that toxic arginine-rich DPRs (poly-GR and poly-PR), but not the non-toxic poly-GP, target NPC hydrogel mimics and block selective entry of a key nuclear transport receptor, importin beta (Impβ). The ease with which these synthetic hydrogel mimics can be adjusted/altered makes them an invaluable tool to dissect complex molecular interactions that underlie cellular transport processes and their perturbation in disease.

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Data is available from the authors on request.

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Acknowledgements

The IUB Light Microscopy Imaging Center is gratefully acknowledged for access to confocal microscopy. S.B. acknowledges an EMBO Long Term Fellowship.

Funding

This work received funding from the National Science Foundation, DMR Biomaterials Award 0906843.

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Correspondence to Steven Boeynaems or Lane A. Baker.

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Friedman, A.K., Boeynaems, S. & Baker, L.A. Synthetic hydrogel mimics of the nuclear pore complex for the study of nucleocytoplasmic transport defects in C9orf72 ALS/FTD. Anal Bioanal Chem 414, 525–532 (2022). https://doi.org/10.1007/s00216-021-03478-2

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  • DOI: https://doi.org/10.1007/s00216-021-03478-2

Keywords

  • ALS
  • Hydrogel
  • Biomimetic
  • C9orf72
  • Biomolecular condensate
  • Nuclear pore complex