Make the spiders of the Fluorescent red silk This is the result obtained by researchers from the University of Bayreuth in a recent study published in the scientific journal Angewandte Chemie. But what was their purpose? The goal was not to produce more beautiful cobwebs or to lay the foundations to create spider-man, rather, research aimed to demonstrate that thegenetic editingin particular the technique Crispr-Cas9can also be applied in arachnidsallowing you to precisely change the DNA. In fact, the spiders are little studied in the laboratory being a heterogeneous group, with a complex genome and are difficult to breed and keep in the laboratory because of their cannibal nature.
In the study, researchers used genetic engineering techniques to modify a small portion of DNA in the spider Parasteodada Tepidariorumbelonging to the Therididae family, inserting the code to produce one fluorescent red protein (Red Fluorescent Protein – RFP) in the gene that codes for spidroinethe proteins that make up the silk. The success of these experiments allows to lay the foundations for further studies in the context of material science but also to understand it development el ‘evolution of spiders.
Make fluorescent red silk spiders produce: how researchers did
The author of the research, Thomas Scheibeland his collaborators made use of the genetic engineering technique Crispr-Cas9 To change the DNA of spiders and obtain the desired results. The technique in question has proved to be revolutionary for biology since its discovery so as to be worth the nobel prize for chemistry in 2020 a Jennifer Doudna And Emmanuelle Charpentier.
The CRISPR-CAS9 system uses a protein which works as a real molecular scissor led by a RNA filament which indicates the exact point where to cut DNA. Once the protein -na complex binds to DNA and cut it, the original segment can be:
- Removed (knock-out): if a “mold” for repair is not provided.
- Replaced or modified (KNOCK-IN): if a DNA “mold” is provided for repair or insertion.
Researchers through genetic editing first deactivated a gene involved in development of the eye and subsequently they changed the gene that codes for the spidroinethe proteins of the silkinserting the RFPthe fluorescent red protein.
The use of fluorescent proteins such as the RFP (or the GFP, Green Fluorescent Protein) is one common practice in the laboratoryespecially with model organisms. This is because they provide animmediate visual indication Of the success of the experiment: in the case of the spider, if the silk shines when illuminated by a specific wavelength, it means that the genetic modification took place correctly.
To genetically change the spider Parasteodada Tepidariorum Scientists have developed one injectable solution which contained a system the editing system described first to include the gene sequence of the red fluorescent protein. The solution was then injected into the oocytes of female spiders do not fertilize that, when they mate with the males, they produced one genetically modified offspring.
Genetically modified spiders: future results and perspectives
Before the work of the University of Bayreuth there were no studies and genetic editing data on spiders, techniques used for example in mosquitoes. For this reason, the researchers first experienced the “simpler thing”: to deactivate a gene, avoiding the production of the protein associated with it. Deactivating a gene that controls the development of the eyes, scientists have obtained raves without eyes, confirming its role in this process, but above all validating the success of the technique.
At this point they moved on to the next step, insert a new sequence for Change the silk produced by the spidera substance produced by special incredibly resistant glands (with the same weight is more robust than steel and Kevlar) and studied in the scientific field being biodegradable, light, tear -resistant and elastic. The silk produced by these spiders exposed to a light with an appropriate wavelength emits a red light (650 nm or more) when it is displayed under a microscope.
For the authors this research, not only could it help to understand i Development mechanisms of spiders, but can also open the way to studies in the material sciencewith the possibility of functionalize These fibers, or to modify them to improve and alter their properties. The goal could be to make them, for example, more resistant or more elasticopening the way to innovative materials with applications in various fields, as reported by Scheibel:
The possibility of applying the CRISPR genetic editing to spider silk is very promising for research in the science of materials: for example, it could be used to further increase the already high resistance to the traction of spider silk.
