Silkworms Engineered for Super Silk

Experts have been trying to modify silkworm genes to create silk with new properties, like spider silk's strength. This goal is faced with numerous challenges, but researchers from Jiangsu University of Science and Technology in China and partners explored using various techniques for genetically engineering silkworms, such as TALENs and transposon-mediated transformation.

These methods involve adding genes for specific silk proteins: a spider silk protein and a bagworm silk protein. The results showed that the engineered silkworms produced more of these new silk proteins (up to 64%) than regular silk. The silk fibers were also much tougher, some by as much as 86%.

The researchers looked closer at the silk fibers and found a key reason for the increased toughness: a higher level of crystallinity. This means the silk fibers are more organized, like tiny crystals packed together. Additionally, the new genes contained special repeating sequences that helped with this organization. Further analysis revealed that such changes did not affect the other silkworm genes.

The findings of the study could lead to the development of custom-designed silks using genetically engineered silkworms as tiny silk factories.

Read more in PNAS Nexus.