The world of science is abuzz with the ambitious project of sequencing the genomes of all life on Earth, and at the forefront of this endeavor is the Wellcome Sanger Institute. In this article, we delve into the fascinating process of hunting and sequencing tardigrades, the microscopic marvels that can withstand extreme conditions. Witek Morek, a postdoctoral researcher and tardigrade expert, embarks on a journey to collect samples, including moss and lichen, from the institute's campus. The goal is to sequence the genomes of these resilient creatures, which can survive searing heat, extreme cold, and even a spell in outer space.
The process begins with the collection of samples, which are then carefully placed in a beaker of water. Within minutes, tardigrades emerge, and Morek's keen eye identifies and confirms their presence under a microscope. These tiny creatures, about 350 micrometres in length, are fascinating in their own right. Some tardigrades are voracious carnivores, preying on nematodes, while others demonstrate parental care by shedding their skin with eggs safely inside.
The sequencing process is a delicate one. Morek must manually disrupt the tardigrade specimens, a challenging task given their tiny size and the limited amount of DNA they contain (just 200 to 500 picograms). The Wellcome Sanger Institute employs a unique approach called the picogram inputi multimodal sequencing protocol, which involves extracting genomic DNA and RNA, amplifying the fragments, and checking the quality of the DNA produced.
The tardigrade genomes are small, 30 times smaller than the human genome, which makes the sequencing process more manageable. The data is then available on the institute's computer cluster, where scientists can pinpoint the genes and proteins required for various processes, such as anhydrobiosis (resistance to desiccation) and cryobiosis (resistance to freezing).
The implications of sequencing tardigrade genomes are far-reaching. By understanding their evolutionary relationships, scientists can uncover new insights into biomedicine and biotechnology. For instance, if a certain protein is crucial in anhydrobiosis, it could be used to produce dry vaccines or enhance crop resistance to drought. As Morek notes, the more we know, the more questions we ask, making this a never-ending scientific adventure.
Beyond the scientific pursuits, the article also highlights the importance of invertebrates in our ecosystem. The annual Guardian invertebrate of the year contest celebrates the wonders of spineless creatures, such as snails, spiders, and corals, which play vital roles in pollination, soil-making, and water purification. Despite their significance, these creatures often go unnoticed, and it is time to recognize their invaluable contributions to the planet.
In conclusion, the sequencing of tardigrade genomes is a remarkable feat of scientific endeavour, offering insights into the resilience and adaptability of these microscopic life forms. Simultaneously, it underscores the importance of preserving and understanding the diverse world of invertebrates, which, as the legendary biologist EO Wilson noted, 'need us more than we need them'.
