Scientists discover ‘lost world’ of our early ancestors in billion-year-old rocks

Newly discovered biomarker signatures point to a whole range of previously unknown organisms that dominated complex life on Earth about a billion years ago. They differed from complex eukaryotic life as we know it, such as animals, plants and algae in their cell structure and likely metabolism, which was adapted to a world that had far less oxygen in the atmosphere than today. Benjamin Nettersheim from the MARUM – Center for Marine Environmental Sciences, University of Bremen and Faculty of Geosciences at the University of Bremen and an international team of researchers now report on this breakthrough for the field of evolutionary geobiology in the journal Nature.

Quelle: IDW Informationsdienst Wissenschaft

Mitochondria and the evolutionary roots of cancer

Cancer is a group of almost 200 diseases that involve variety of changes in cell structure, morphology, and physiology. Cancer phenotype is underlying several alterations in cellular dynamics with three most critical features, which includes self-sufficiency in growth signals and insensitivity to inhibitory signals, evasion of programmed cell death and limitless replicative potential with a potential for the invasion of other organs. Cancer disease is widespread among metazoans. Some properties of cancer cells such as uncontrolled cell proliferation, lack of apoptosis, hypoxia, fermentative metabolism and free cell motility, i.e. metastasis, resemble a prokaryotic lifestyle, which leads to the assumption of a reversal like evolution from eucariotic back to proteobacterial state. This phenotype matches the phenotype of the last universal common ancestor (LUCA) that resulted from the endosymbiosis between archaebacteria and α-proteobacteria, which later became the mitochondria.

 Davila AF and Zamorano P (2013) Mitochondria and the evolutionary roots of cancer. Phys. Biol. 10 (2013) 026008, doi:10.1088/1478-3975/10/2/026008