Mass spider silk production through targeted gene replacement in Bombyx mori

Abstract

SignificanceThe use of heterologous systems to express spider silk has become an attractive method. However, achieving cost-effective production and high yields is still challenging. Here, we describe the establishment of a targeted gene replacement system in Bombyx mori to express the major ampullate spidroin-1 gene (MaSp1) from the spider Nephila clavipes. With the aid of transcription activator-like effector nuclease-mediated homology-directed repair, we genetically replaced the silkworm fibroin heavy chain gene with MaSp1 with considerable transformation efficiency, and the chimeric MaSp1 yields reached up to 35.2% wt/wt of cocoon shells in transformed silkworms. The genetically modified silk fiber had significant changes in mechanical properties, with improved extensibility. This system will shed light on the future mass production of new biomaterials, including spider silk.

Salt‐Assisted Toughening of Protein Hydrogel with Controlled Degradation for Bone Regeneration

“…The degradation rate of hydrogels used for bone regeneration should match the rate of bone regeneration; hard callus remodeling, i.e., secondary bone formation, begins 21 days after bone fracture and lasts for different amounts of time in different anatomical sites and in different mammals . Defects in the rat calvaria with a diameter of 5 mm typically heal within 12 weeks . Therefore, the basic time requirement for the maintenance of RSF/G hydrogels in vivo for bone regeneration is 12 weeks, with controlled degradation according to the bone regeneration process .…”

“…Defects in the rat calvaria with a diameter of 5 mm typically heal within 12 weeks . Therefore, the basic time requirement for the maintenance of RSF/G hydrogels in vivo for bone regeneration is 12 weeks, with controlled degradation according to the bone regeneration process . In this study, we introduced HRP to crosslink the RSF network and control the release of hydrolytically degradable units of RSF and gelatin peptide.…”

Mechanically Strong Globular‐Protein‐Based Fibers Obtained Using a Microfluidic Spinning Technique

“…Protein‐based fibers, such as spider silks, have attracted considerable interest because of their extraordinary mechanical properties . Those fibrous proteins contain typical rigid domains, such as β‐sheet or α‐helix, and flexible structures that are determined by amorphous domains .…”

Mechanically Strong Globular‐Protein‐Based Fibers Obtained Using a Microfluidic Spinning Technique

“…Protein‐based fibers, such as spider silks, have attracted considerable interest because of their extraordinary mechanical properties . Those fibrous proteins contain typical rigid domains, such as β‐sheet or α‐helix, and flexible structures that are determined by amorphous domains .…”