Tracking down the origin of complex living things

Figure 1: Cryo-electron tomography provided insight into the cellular structure of a newly cultured Asgard archaeon illustrated here. Note the extensive actin cytoskeletal filaments ( orange ) in the cell bodies and cell processes, as well as the uniquely constructed cell envelope ( blue ). Margot Riggi, The Animation Lab, University of Utah) Researchers at the University of Vienna and ETH Zurich cultivate "missing link" microorganism How did the complex living things on earth come into being? This is one of the great unanswered questions in biology. A collaboration between the research groups of Christa Schleper at the University of Vienna and Martin Pilhofer at ETH Zurich has brought the answer one step closer. The researchers succeeded in cultivating a special archaeon and characterizing it more precisely using microscopic methods. This representative of the Asgard archaea exhibits unique cellular features and could be an evolutionary "missing link" to the more complex life forms such as animals and plants. The study is currently published in the journal "Nature" . Living organisms on Earth are divided into three major domains: Eukaryotes, Bacteria, and Archaea. Eukaryotes include the groups of animals, plants and fungi. Their cells are generally much larger and, at first glance, more complex than cells of bacteria and archaea. For example, the genetic material of eukaryotes is packaged in a nucleus, and the cells also have a variety of other compartments. The cell shape and transport within the eukaryotic cell are also based on an extended cytoskeleton. But how did the evolutionary leap to such complex eukaryotic cells occur?