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Peripheral nerve reconstruction through the employment of nerve guidance conduits with Trichonephila dragline silk as a luminal filling has emerged as an outstanding preclinical alternative to avoid nerve autografts. Yet, it remains unknown whether the outcome is similar for silk fibers harvested from other spider species. This study compares the regenerative potential of dragline silk from two orb‐weaving spiders, Trichonephila naurata and Nuctenea umbratica, as well as the silk of the jumping spider Phidippus regius. Proliferation, migration, and transcriptomic state of Schwann cells seeded on these silks are investigated. In addition, fiber morphology, primary protein structure, and mechanical properties are studied. The results demonstrate that the increased velocity of Schwann cells on Phidippus regius fibers can be primarily attributed to the interplay between the silk's primary protein structure and its mechanical properties. Furthermore, the capacity of silk fibers to trigger cells toward a gene expression profile of a myelinating Schwann cell phenotype is shown. The findings for the first time allow an in‐depth comparison of the specific cellular response to various native spider silks and a correlation with the fibers’ material properties. This knowledge is essential to open up possibilities for targeted manufacturing of synthetic nervous tissue replacement.
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This content will become publicly available on April 14, 2026
Native Silk Fibers: Protein Sequence and Structure Influences on Thermal and Mechanical Properties
Silk fibers produced by arthropods have inspired an array of materials with applications in healthcare, medical devices, textiles, and sustainability. Silks exhibit biodiversity with distinct variations in primary protein constituent sequences (fibroins, spidroins) and structures across taxonomic classifications, specifically the Lepidopteran and Araneae orders. Leveraging the biodiversity in arthropod silks offers advantages due to the diverse mechanical properties and thermal stabilities achievable, primarily attributed to variations in fiber crystallinity and repeating amino acid motifs. In this review, we aim to delineate known properties of silk fibers and correlate them with predicted protein sequences and secondary structures, informed by newly annotated genomes. We will discuss established patterns in repeat motifs governing specific properties and underscore the biological diversity within silk fibroin and spidroin sequences. Elucidating the relationship between protein sequences and properties of natural silk fibers will identify strategies for designing new materials through rational silk-based fiber design.
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- Award ID(s):
- 2217159
- PAR ID:
- 10591300
- Publisher / Repository:
- ACS Biomacromolecules
- Date Published:
- Journal Name:
- Biomacromolecules
- Volume:
- 26
- Issue:
- 4
- ISSN:
- 1525-7797
- Page Range / eLocation ID:
- 2043 to 2059
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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