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Categories: Biology: Developmental, Paleontology: Fossils

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Leading edge technology has uncovered secrets about a world-renowned fossil hoard that could offer vital clues about early life on Earth. Researchers who analyzed the 400 million-year-old cache, found in rural north-east Scotland, say their findings reveal better preservation of the fossils at a molecular level than was previously anticipated.

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A cytokinin-mediated, proliferation-based mechanism is involved in the generation and maintenance of cell-type specific tissue boundaries during vascular development in Arabidopsis roots. Specifically, the HANABA-TARANU transcription factor forms a feed-forward loop to cytokinin signaling, which in turn regulates the position and frequency of cell proliferation of proto-vascular cells such that mechanical stress of the surrounding tissues guides growth in an apical-oriented manor, maintaining cell patterning throughout the tissue section.

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The human immunodeficiency virus HIV-1 is able to infect various tissues in humans. Once inside the cells, the virus integrates its genome into the cellular genome and establishes persistent infections. The role of the structure and organization of the host genome in HIV-1 infection is not well understood. Using a cell culture model based on brain immune microglia cells, an international research team has now defined the insertion patterns of HIV-1 in the genome of microglia cells.

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'Miniature shredders' are at work in each cell, disassembling and recycling cell components that are defective or no longer required. The exact structure of these shredders differs from cell type to cell type, a study now shows. For example, cancer cells have a special variant that can supply them particularly effectively with building blocks for their energy metabolism.

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Geneticists have written new chapters in the reconstruction of pre-colonial Americas history after using DNA from the indigenous Ashaninka people from Amazonian Peru. They have discovered previously unexpected levels of genetic variation in this group and uncovered a strong hint that these people were involved in a South-to-North migration that led to the transition from an archaic to ceramic culture in the Caribbean islands.

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Researchers have now encapsulated the young field of nucleolar DNA damage response (DDR) pathways. A new review highlights six mechanisms by which cells repair DNA damage. By attacking these mechanisms, future applied researchers will be able to trip up cancer's reproduction and growth.

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A new study explores exactly what leads to the generation of Th17 cells -- an important subtype of cells in the intestine -- and uncovers some of the underappreciated molecular players and events that lead to cell differentiation in the gut.

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With the aid of some sea slugs, chemists have discovered that one of the smallest conceivable tweaks to a biomolecule can elicit one of the grandest conceivable consequences: directing the activation of neurons. The team has shown that the orientation of a single amino acid -- in this case, one of dozens found in the neuropeptide of a sea slug -- can dictate the likelihood that the peptide activates one neuron receptor versus another. Because different types of receptors are responsible for different neuronal activities, the finding points to another means by which a brain or nervous system can regulate the labyrinthine, life-sustaining communication among its cells.

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Meiotic recombination assures genetic variation during breeding. During meiotic prophase I, chromosomes are organized in a loop-base array by a proteinaceous structure called meiotic chromosome axis which is critical for meiotic recombination and genetically diverse gametes. An international research team reports the application of a TurboID (TbID)-based approach to identify proteins in proximity of meiotic chromosome axes in Arabidopsis thaliana. Not only known but also new meiotic proteins were uncovered.

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A whole new world of antibiotics is waiting inside the viruses that infect bacteria. Scientists are making it easier to study them.

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The skeleton, tendons, and glands of a functional jaw all derive from the same population of stem cells, which arise from a cell population known as neural crest. To discover how these neural crest-derived cells know to make the right type of cell in the right location, researchers focused on a particular gene, Nr5a2, that was active in a region of the face that makes tendons and glands, but not skeleton. To understand the role of Nr5a2, the scientists created zebrafish lacking this gene. These mutant zebrafish generated excess cartilage and were missing tendons in their jaws.

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Researchers have created a radical new view of how immune cells recognise threats such as viruses. The discovery could be used to design better vaccines and to gain a deeper insight into autoimmune diseases and allergies.

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Most cells in the bodies of living things duplicate their contents and physically separate into new cells through the process of cell division. But across many species, germ cells, those that become eggs or sperm, don't fully separate. They remain interconnected through small bridges called ring canals and cluster together. In a new study, researchers uncover how it is that germ cells in fruit flies form these ring canals, a finding that they say will provide new insights into a widely shared feature of development and into diseases in which cell division is disrupted.

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Billions of sea anemones adorn the bottom of the Earth's oceans -- yet they are among the rarest of fossils because their squishy bodies lack easily fossilized hard parts. Now a team of paleontologists has discovered that countless sea anemone fossils have been hiding in plain sight for nearly 50 years. It turns out that fossils long-interpreted as jellyfish were anemones. To do so, a team of scientists has simply turned the ancient animals upside down.

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Germination is a crucial stage in the life of a plant as it will leave the stage of seed resistant to various environmental constraints (climatic conditions, absence of nutritive elements, etc.) to become a seedling much more vulnerable. The survival of the young plant depends on the timing of this transition. It is therefore essential that this stage be finely controlled. Botanists have now discovered the internal thermometer of seeds that can delay or even block germination if temperatures are too high for the future seedling. This work could help optimize plant growth in a context of global warming.

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New methodology and tools provide an opportunity to watch in unprecedented detail as a phage attacks a bacterium.

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Obese fruit flies are the experimental subjects in a study of the causes of muscle function decline due to obesity. In humans, skeletal muscle plays a crucial role in metabolism, and muscle dysfunction due to human obesity can lead to insulin resistance and reduced energy levels.

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The findings offer a new way to understand how some ants become total layabouts.

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An international team of bee researchers has integrated a calcium sensor into honey bees to enable the study of neural information processing including response to odors. This also provides insights into how social behavior is located in the brain.

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Scientists recently developed an efficient way to transplant pancreatic islets and demonstrated that the method can effectively reverse type 1 diabetes in nonhuman primates.