Spiderman powers are now more of a possibility. A new study published in Nature Genetics reveals the genes that hold the secrets to the incredible properties of the spider silk.
Spider silks—basically the substance Spiderman uses to travel and to trap his enemies—are a most wondrous thing, and scientists have tried to look deeper into their potential uses. For one, spider silk can be stronger than steel (hear that, Man of Steel! Spiderman is more powerful!). It can be made tougher and more flexible. Its anti-bacterial and anti-fungal properties coupled with its harmless effect on the human immune system would make it an ideal material for surgery and medical equipment. However, in spite of all these prospects, none of these applications has become reality because of difficulties in identifying the genes coding for the different types of silk. Here’s where the new study changes everything: it provides us with the most extensive research done on spider silk genes.
We now have few more drops from the ocean of knowledge of spider silk. The latter is made of spider silk proteins known as spidroins, which are encoded by specific genes. Prior to the new study, information of spider silk genes was very limited: we only knew of a few genes, despite the fact that research in this field dates back to over 50 years. Subsequent works have only yielded incomplete results, until recently, when a team of scientists from University of Pennsylvania’s Perelman School of Medicine successfully sequenced the complete genome of the golden orb-weaver spider (Nephila clavipes).
The genomic study came with surprising findings: from new silk genes to those coding for properties like strength, toughness, and elasticity, explains senior author Benjamin F. Voight. The study is hoped to fuel research aimed at turning the silk properties into man-made materials.
The golden orb-weaver is considered the ‘lab rat’ of spider silk science. Its genome revealed to be as large as its human counterpart. Over 14,000 genes were identified as potentially expressing spidroins; 28 of these definitely appear to encode for the proteins. The genes, and the patterns within them, account for the uniqueness of different types of silk.
Spider silks exist in many varieties, and therefore, functions. Spidroins are classified into 7 groups based on this. For instance, a category includes silk used to trap prey, and another is used to define the powerful silk used by spiders to swing (this is what Spiderman probably uses). The new work broadens these categories with new spidroins with functions that are, as yet, unknown. Perhaps, more categories need to be added, or the current ones redefined.
Key properties of spider silks might also be unlocked in terms of their genes: the team found repetitive spidroin genes, 400 DNA sequences repeating with small variations. The scientists believe these might be responsible for main characteristics like high-tensile strength and flexibility.
As Voight points out, they discovered much more complexity in the production of silk than was initially expected.
Another interesting discovery is that one of the orb-weaver’s silk proteins has been found to be made by the spider’s venom gland instead of its silk gland. This implies that silk might have other functions than the ones established in science like prey capture, preservation, and immobilisation.
Also, the team have identified over 600 genes that might play a role in transforming liquid silk into solid threads, a process biotechnologists are dying to reproduce.
Well, if we can really unveil the secrets hidden in spidroin genes, maybe someday we can have Spiderman powers?! And, the best is, Voight is not totally joking about this!
“When I say that we’d like to build a ‘web-shooter’ like Spiderman’s in the lab, I’m only half-joking” Voight said.