Mechanism of silk processing in insects and spiders

ABSTRACT Silk spinning by insects and spiders leads to the formation of fibres that exhibit high strength and toughness1. The lack of understanding of the protein processing in silk glands

has prevented the recapitulation of these properties _in vitro_ from reconstituted or genetically engineered silks. Here we report the identification of emulsion formation and micellar

structures from aqueous solutions of reconstituted silkworm silk fibroin as a first step in the process to control water and protein–protein interactions. The sizes (100–200 nm diameter) of

these structures could be predicted from hydrophobicity plots of silk protein primary sequence2. These micelles subsequently aggregated into larger ‘globules’ and gel‐like states as the

concentration of silk fibroin increased, while maintaining solubility owing to the hydrophilic regions of the protein interspersed among the larger hydrophobic regions. Upon physical

shearing or stretching structural transitions, increased birefringence and morphological alignment were demonstrated, indicating that this process mimics the behaviour of similar native silk

proteins _in vivo_. Final morphological features of these silk materials are similar to those observed in native silkworm fibres. Access through your institution Buy or subscribe This is a

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SELF-ASSEMBLY OF SILK PROTEINS THROUGH LIQUID-LIQUID PHASE SEPARATION Article Open access 28 April 2025 MOLECULAR ORGANIZATION OF FIBROIN HEAVY CHAIN AND MECHANISM OF FIBRE FORMATION IN

_BOMBYX MORI_ Article Open access 29 June 2024 THE SILK OF GORSE SPIDER MITE _TETRANYCHUS LINTEARIUS_ REPRESENTS A NOVEL NATURAL SOURCE OF NANOPARTICLES AND BIOMATERIALS Article Open access

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DoD (Air Force). AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Departments of Chemical & Biological Engineering & Biomedical Engineering, Tufts University, Medford, Massachusetts,

02155, USA Hyoung-Joon Jin & David L. Kaplan Authors * Hyoung-Joon Jin View author publications You can also search for this author inPubMed Google Scholar * David L. Kaplan View author

publications You can also search for this author inPubMed Google Scholar CORRESPONDING AUTHOR Correspondence to David L. Kaplan. ETHICS DECLARATIONS COMPETING INTERESTS The authors declare

that they have no competing financial interests. RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Jin, HJ., Kaplan, D. Mechanism of silk processing in

insects and spiders. _Nature_ 424, 1057–1061 (2003). https://doi.org/10.1038/nature01809 Download citation * Received: 22 April 2003 * Accepted: 27 May 2003 * Issue Date: 28 August 2003 *

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