Mass spider silk production through targeted gene replacement in Bombyx mori

Copyright © 2018 the Author(s). Published by PNAS..

Spider silk is one of the best natural fibers and has superior mechanical properties. However, the large-scale harvesting of spider silk by rearing spiders is not feasible, due to their territorial and cannibalistic behaviors. The silkworm, Bombyx mori, has been the most well known silk producer for thousands of years and has been considered an ideal bioreactor for producing exogenous proteins, including spider silk. Previous attempts using transposon-mediated transgenic silkworms to produce spider silk could not achieve efficient yields, due to variable promoter activities and endogenous silk fibroin protein expression. Here, we report a massive spider silk production system in B. mori by using transcription activator-like effector nuclease-mediated homology-directed repair to replace the silkworm fibroin heavy chain gene (FibH) with the major ampullate spidroin-1 gene (MaSp1) in the spider Nephila clavipes We successfully replaced the ∼16-kb endogenous FibH gene with a 1.6-kb MaSp1 gene fused with a 1.1-kb partial FibH sequence and achieved up to 35.2% chimeric MaSp1 protein amounts in transformed cocoon shells. The presence of the MaSp1 peptide significantly changed the mechanical characteristics of the silk fiber, especially the extensibility. Our study provides a native promoter-driven, highly efficient system for expressing the heterologous spider silk gene instead of the transposon-based, random insertion of the spider gene into the silkworm genome. Targeted MaSp1 integration into silkworm silk glands provides a paradigm for the large-scale production of spider silk protein with genetically modified silkworms, and this approach will shed light on developing new biomaterials.

Medienart:

E-Artikel

Erscheinungsjahr:

2018

Erschienen:

2018

Enthalten in:

Zur Gesamtaufnahme - volume:115

Enthalten in:

Proceedings of the National Academy of Sciences of the United States of America - 115(2018), 35 vom: 28. Aug., Seite 8757-8762

Sprache:

Englisch

Beteiligte Personen:

Xu, Jun [VerfasserIn]
Dong, Qinglin [VerfasserIn]
Yu, Ye [VerfasserIn]
Niu, Baolong [VerfasserIn]
Ji, Dongfeng [VerfasserIn]
Li, Muwang [VerfasserIn]
Huang, Yongping [VerfasserIn]
Chen, Xin [VerfasserIn]
Tan, Anjiang [VerfasserIn]

Links:

Volltext

Themen:

9007-76-5
Bombyx mori
Fibroins
Genome editing
Journal Article
Research Support, Non-U.S. Gov't
Spider silk
Spidroin 1
TALEN

Anmerkungen:

Date Completed 02.10.2018

Date Revised 03.02.2019

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1073/pnas.1806805115

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM287218864