This week in A l'UM la science, Simon Galas and Myriam Richaud, both researchers at the Institut des biomolécules Max Mousseron in the Nématodes et tardigrades laboratory, assisted by Morgan Pellerano, engineer at IBMM, open the doors to one of the only two tardigrade farms in France. A long-format report on an extraordinary creature. Broadcast every Wednesday at 6pm on Divergence-FM 93.9.
And this Easter, we're revisiting the miracle of the resurrection, but with a scientific twist. For many years now, an organism has been attracting the attention of the scientific community for its supernatural abilities. Soak it in liquid nitrogen, no problem! Boil it and it's fine! UV-C or cosmic rays, fatal to ordinary mortals, barely tickle it and even give it the brilliance of a neon sign. As for pressure, it quietly withstands that found more than 180 km below the earth's surface. Awe-inspiring!
But it goes even further. For if our mystery guest needs water to function, he can, in the absence of it, go into a state of suspended life to the point where his body resembles nothing more than an old potato chip, waiting for a drop of water to resuscitate him.
So what is this super-organism that concentrates so many super-powers that it's called an extremophile? It's not an April fool, but a tardigrade. A metazoan no bigger than a millimeter in size that has been resisting everything for over 500 million years. They're all around us, as long as there's a bit of water and greenery, and they walk around with the adorable look of a miniaturized teddy bear. And we're lucky in that Montpellier is home to one of only two tardigrade farms in France. It's at the Institut des biomolécules Max Mousseron on the CNRS campus, and that's where we're taking you for a long-form report with Simon Galas and Myriam Richaud, both researchers in the Nématodes et tardigrades lab, assisted by Morgan Pellerano, engineer... and breeder.
Adult tardigrade "Ramazzottius varierornatus" viewed by scanning electron microscopy. Tardigrades are animals measuring around 1 mm long, with eight legs and, in some species, a pair of ocelli (light-sensitive organs). Present on Earth for almost 500 million years, living in all environments, tardigrades possess the highest resistance capacities on the planet. They survive dehydration, extreme pressures and temperatures, and radiation. The GigaTardi project explores the interior of tardigrades using several techniques to reveal their stress resistance strategies. UMR5247 Institut des Biomolécules Max MousseronAdult Tardigrade "Hypsibius exemplaris" viewed ventrally under confocal laser scanning microscopy after treatment with a product that colors its mitochondria (intracellular organelles responsible for respiration) red. Red spheres with patterns inside can be seen. These storage cells move throughout the animal to bring nutrients to other cells (muscles, neurons, digestive tract, etc.). Tardigrades are animals measuring around 1 mm long, with eight legs and, in some species like this one, a pair of ocelli (light-sensitive organs). "Hypsibius exemplaris" is transparent, which makes it possible to visualize internal structures using dyes. Present on Earth for almost 500 million years, living in all environments, tardigrades have the highest resistance capacities on the planet. In particular, they can survive extreme pressures (up to 7.5 GPa) without damaging their internal structures. The GigaTardi project explores the interior of tardigrades using several techniques, to reveal their stress resistance strategies. UMR5247 Institut des Biomolécules Max MousseronTardigrade "Hypsibius exemplaris" seen, ventral side, under confocal laser scanning microscopy after treatment with products that stain muscles green and DNA blue. Tardigrades are animals measuring around 1 mm in length, with eight legs and, in some species like this one, a pair of ocelli (light-sensitive organs). "Hypsibius exemplaris" is transparent, which makes it possible to visualize internal structures using dyes. Tardigrades have muscles, neurons, an intestine and a microbiome. Present on Earth for almost 500 million years, living in all environments, tardigrades have the highest resistance capacities on the planet. In particular, they can survive extreme pressures (up to 7.5 GPa) without damaging their internal structures. The GigaTardi project explores the interior of tardigrades using several techniques, to reveal their stress resistance strategies. UMR5247 Institut des Biomolécules Max MousseronTardigrade "Hypsibius exemplaris" seen under confocal laser scanning microscopy (side view). Tardigrades are animals about 1 mm long, with eight legs and, in some species like this one, a pair of ocelli (light-sensitive organs). This species carries out two operations at the same time: laying eggs and moulting (changing skin). In this image, obtained with a special filter, we can see six embryos laid and abandoned in the moult (old skin) by the adult. Present on Earth for almost 500 million years, living in all environments, tardigrades have the highest resistance capacities on the planet. They survive dehydration, extreme pressures and temperatures, and radiation. The GigaTardi project explores the interior of tardigrades using several techniques to reveal their stress resistance strategies. UMR5247 Institut des Biomolécules Max MousseronA tardigrade "Hypsibius exemplaris" molting embryos, as seen by confocal laser scanning microscopy (side view). Tardigrades are animals about 1 mm long, with eight legs and, in some species like this one, a pair of ocelli (light-sensitive organs). This species carries out two operations at the same time: laying eggs and moulting (changing skin). In the image, six embryos have been laid and abandoned in the molt (old skin) by the adult. We can also see the tips of the adult's legs, capped by the species' characteristic claws. Present on Earth for nearly 500 million years, living in all environments, tardigrades possess the planet's highest resistance capacities. They survive dehydration, extreme pressures and temperatures, and radiation. The GigaTardi project explores the interior of tardigrades using several techniques to reveal their stress resistance strategies. UMR5247 Institut des Biomolécules Max MousseronTardigrade "Hypsibius exemplaris", ventral side, and its embryos seen under confocal laser microscopy. Tardigrades are animals about 1 mm long, with eight legs and, in some species like this one, a pair of ocelli (light-sensitive organs). This species carries out two operations at the same time: laying eggs and moulting (changing skin). In the picture, four already laid embryos are still cohabiting in the same skin with the adult. In a few minutes, the adult will extract itself from the moult and leave them behind. We can also make out the adult's ocelli and a few claws at the end of its legs. Present on Earth for almost 500 million years, living in all environments, tardigrades possess the planet's highest resistance capacities. They survive dehydration, extreme pressures and temperatures, and radiation. The GigaTardi project explores the interior of tardigrades using several techniques to reveal their stress resistance strategies. UMR5247 Institut des Biomolécules Max Mousseron
Simon GALAS Myriam RICHAUD IBMM Univ. Montpellier ENSCM CNRS Images
