The CRISPR-CAS9 molecular tool has sparked a revolution in genetic engineering, acting as the most precise molecular scissors to edit genomes. The CAS9 enzyme, guided by RNA, can remove unwanted genes, correct mutations, or insert new genetic sequences with unparalleled accuracy. This method has been transforming various fields such as agriculture, medicine, and microbiology, and now it has made its debut in the realm of arachnids.
Scientists at the University of Bayreuth have successfully created the first genetically modified spider capable of spinning a fluorescent red cobweb. They chose a common species, Parasteatoda tepidariorum, for the experiment, marking a significant milestone in genetic research involving arachnids.
Working with spiders presented challenges due to cannibalism among individuals and the complexity of their genome structure. To overcome these obstacles, biologists devised a unique CRISPR-based solution containing genes for red fluorescent protein synthesis, which they introduced into non-compliant eggs.
Precise microinjections, carried out on immobilized spiders using carbon dioxide, proved crucial for the experiment. Following the injections, females were crossed with males that had an identical appearance, resulting in offspring capable of producing threads with the introduced red protein. Notably, this genetic modification did not interfere with the natural process of fiber formation.
The newly created spider silk boasts impressive characteristics, combining exceptional tensile strength and elasticity with lightness and biodegradability. The success of this experiment paves the way for the development of innovative materials with applications ranging from medical use in surgical threads and artificial tissue growth to the production of super-strong protective fabrics and “smart” materials with tailored properties.
In addition to producing luminous threads, the researchers explored the CRISPR-KO methodology, enabling the selective deactivation of specific genes. Their focus was on the “so” gene, believed to be responsible for eye formation in spiders. By disabling its function, the researchers confirmed that the absence of this gene resulted in offspring lacking eyes.