Creepy creatures reveal DNA secrets

Whether you are afflicted with arachnophobia or not, it may surprise you to know that there are many positive reasons to study spiders and their DNA. Did you know that studying the molecular make-up of spider venom can help produce anti-venoms, as well as design new drugs and medical treatments? Spiders can be handy in agricultural ecosystems where they act as natural pest control, and while not everyone loves a spider in their bath, they can help keep flies out of your home.

The Sanger Institute’s Marco Meyer is a researcher travelling up and down the UK collecting eight-legged friends. He has sampled key spider species from North Wales, Norfolk, Cambridgeshire, Surrey, and has many more sample locations on his list thanks to invitations from a variety of UK-based experts.

While doing fieldwork in North Wales with the local arachnid society, Marco Meyer inspects heathlands for spiders only found in this special habitat. Credit (L) Marco Meyer; (R) Chris Fletcher, Natural History Museum

Marco says, “My research background is in functional morphology – how do web building spiders avoid getting stuck in their own webs? I studied the antiadhesive nanostructures  that allow them to steer clear of their own snares – but beyond that, I am passionate about how spiders adapt their form and behaviour to their environment.”

Marco’s spider trips are about more than exploring the great outdoors, studying spiders is a priority to be able to track populations, monitor species on the brink of extinction, and in general learn more about their fascinating biology and behaviour. His work is part of a wider project called the Darwin Tree of Life Project that aims to create a huge digital DNA resource of all insects, plants, and animals found in Great Britain and Ireland, with spiders being just one leg of this bigger beast.

Bats are flying mammals with a wide range of food sources and habits. Amazingly, one in every five living mammals is a bat with over 1,300 species spread across the globe. They live in many different types of places, from caves to abandoned buildings. Within all this tremendous diversity, most of them have one thing in common — they come out at night. Alongside their nocturnal lifestyles, bats have been famously integrated into spooky and scary culture by their association with vampirism, with the 1897 publication of Bram Stoker's ‘Dracula’ describing vampires that transform into bats.

Given that bats are not on most peoples’ cute and cuddly list, why do we study their DNA? Well, bat genome sequences could help us understand how these remarkable creatures are resistant to cancer, and many other diseases. By using bat DNA to build a family tree, researchers can explore the evolution of these fascinating creatures with immune systems that can evade disease, and maybe learn a thing or two that could help humans too.

The bats Plecotus auritus and Myotis daubentoni have had their genomes sequenced. Image credits: Fourrue / Wikimedia Commons and Gilles San Martin / Wikimedia Commons.

Will this worm haunt your dreams? This creature might not feature in a famous 19^th century gothic novel, but it does haunt the record books as the longest animal on the planet. One specimen was measured as 55 metres! This record is contested though, as the ribbon worm only reaches extreme lengths when fully stretched out — they are remarkably elastic.

Scientists are interested in the worms themselves, but there are other motives to peer into the DNA of this wriggly creature. Researchers hope that the genomes of these worms will help uncover new chemical compounds for use in agriculture, biotechnology and medicine.

“They’re not cute or charismatic. They have toxic mucus. But I like them because no one is rooting for them – and we know so little about them,” said Patrick Adkins from the Marine Biological Association, who works closely with teams at the Sanger Institute.

Having studied the toxins produced by this worm used to paralyse and kill green crabs, researchers have identified potential new insecticides that affect cockroaches in a similar way, but are not harmful to mammals.

Mark Blaxter, Head of the Tree of Life Programme at the Sanger Institute, said: “The genome sequences of animals like the Giant Ribbon Worm will aid a whole new generation of research – including the discovery of new active molecules for medicine and other applications. There are many groups of creatures where we know very little beyond the fact that they exist, and we are working to genetically understand each and every one.”

This impressive beetle known as the Devil’s Coach Horse, had to make our list of spooky creatures the Sanger Institute has studied.  Did you know that it used to be thought that squashing a Devil's Coach-Horse beetle was good for your soul?

While they aren't really evil, so no need to squash them, the Devil's Coach Horse beetle can give humans a painful bite. It is one of the largest beetles in the UK, with sharp pincer mouthparts, oversized mandibles, and a jet-black appearance. When threatened, the Devil’s Coach Horse beetle will curl up its abdomen to look like a scorpion ready to strike.

So, it is best to keep your eyes peeled for them all year-round, not just in October. Interesting facts aside, why are scientists peering into the DNA of these and other beetles? Having genomes for multiple beetle species, and 3000 other insects, is critical as it enables biologists to compare genomes and understand their differences. As Professor Peter Holland of the University of Oxford and a collaborator with the Darwin Tree of Life Project adds, “We would never be able to spot the specific adaptations of one species of beetle unless we compare it to its relatives – only then can we peer into the evolutionary history of every beetle gene.”

Hellweed, dodder, or strangle-tare as it is also eerily known, is a parasitic plant that creates red webs over other plants. Due to its ability to infect crop plants such as alfalfa, and because its seeds survive over long periods in a dormant state, Hellweed can be one hell of a problem for agricultural crops. Once restricted to Europe, it is now widespread from China all the way to the Americas, causing a real-life nightmare for farmers around the world.

Experts, including those at the Sanger Institute, are delving into the DNA of this plant. DNA sequencing parasitic plants like Hellweed could help researchers understand host-parasite interactions and learn more about the inner-workings of parasitic plants.

Thanks mycology experts from Kew Gardens, a sample of the fungi known as Devil’s Fingers or Octopus Stinkhorn will arrive soon at the Sanger Institute for DNA extraction and analysis. When this fungus is mature, it smells of putrid flesh. Researchers receiving the sample may be warned to don special protective equipment to avoid inhaling its stench!

The Devil's fingers. Photos by Dr. Hans-Günter Wagner (left) and Michel Langeveld (right) / Wikimedia Commons.

The bad smell does serve a purpose for the fungi by attracting flies which then spread the spores, allowing for the next generation of Devil’s Fingers to rise from the soil. Studying the DNA of fungi such as Devil’s Fingers could help researchers understand how plants attract pollinators, interact with their environment, and even how plants can affect humans.

Lucky number seven for our spooky sequenced creatures is the Fire Coral, known for its ability to cause itchy burning sensations upon contact with skin that can last for days. The name coral is somewhat misleading, as Fire Corals are not true corals but are instead more closely related to Hydra (think of them as skinny sea anemones) and other hydrozoans, making them hydrocorals. The Aquatic Symbiosis Genomics Project is studying the DNA of Fire Coral, and many other aquatic creatures that live in a close relationship with a different organism. The project is sequencing the genomes of lots of different types of corals, creating an open access tool for scientists all over the world working to save corals from dying. Next time you are diving in a coral reef, watch out for Fire Coral or you’ll be sorry for swimming past it for days to come.