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Phytoplankton could be sea cyclists, collective behaviour in 480-million-year-old arthropods and import mechanisms of HIV

By 22nd October 2019 February 10th, 2020 No Comments

An international team, including researchers from the Institut de mécanique des fluides de Toulouse (IMFT, CNRS/Toulouse INP/UT3 Paul Sabatier), the ETH University in Zurich and the University of Sheffield, has been working on quantifying why some micro-organisms swim as chains, much like a line of cyclists. The new work suggests that these mechanisms are  important for many gyrotactic phytoplankton species in helping them cross  turbulent areas of the ocean in a vertical direction. These results are published in Science Advances.

Source: INSIS

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© IMFT

Our understanding of the anatomy of the earliest animals has never been better, but we still know next to nothing about their behaviour. Did group behaviour arise recently or is it primeval? To answer this question, researchers from the CNRS, the University of Poitiers, UBO, Claude Bernard Lyon 1 University, Cadi Ayyad University (Marrakech, Morocco), and the University of Lausanne (Switzerland) say they have studied fossilized Moroccan Ampyx trilobites, which lived 480 million years ago. The researchers showed that the trilobites had probably been buried in their positions—all oriented in the same direction, in orderly lines, maintaining close contact with each other through their long spines—during storms. The research is detailed in Scientific Reports.

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© Jean Vannier, Laboratoire de géologie de Lyon : Terre, planètes, environnement (CNRS/ENS de Lyon/Université Claude Bernard Lyon 1)

Finally, like all viruses, the human immunodeficiency virus, or HIV, parasitizes the cell it infects so that it can multiply and release new viruses. To do this, the virus needs to divert the proteins from the cell it infects to its own benefit because it does not have all the components necessary spread itself. The proteins of the human cell can thus somehow be crucial allies for the virus. Identifying these proteins is therefore important for understanding the replication cycle of the virus and potentially inhibit it. In a new study published in Nature Microbiology, researchers at the Institut de recherche en infectiologie de Montpellier (IRIM) – (CNRS / Université de Montpellier) describe how they discovered that the human protein Transportin or TRN-1 allows the virus to replicate effectively.

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© Sébastien Lyonnais