Showing 20 articles starting at article 61
< Previous 20 articles Next 20 articles >
Categories: Biology: Developmental, Paleontology: Climate
Published First ever 3D reconstruction of 52,000-year-old woolly mammoth chromosomes thanks to serendipitously freeze-dried skin
(via sciencedaily.com) Original source An international research team has assembled the genome and 3D chromosomal structures of a 52,000-year-old woolly mammoth -- the first time such a feat has been achieved for any ancient DNA sample. The fossilized chromosomes, which are around a million times longer than most ancient DNA fragments, provide insight into how the mammoth's genome was organized within its living cells and which genes were active within the skin tissue from which the DNA was extracted. This unprecedented level of structural detail was retained because the mammoth underwent freeze-drying shortly after it died, which meant that its DNA was preserved in a glass-like state.
Published Phage-derived enzyme targets E. faecalis biofilms to mitigate acute graft-versus-host disease
(via sciencedaily.com) Original source Acute graft-versus-host disease occurs when donor immune cells attack the recipient's tissues after an allogeneic hematopoietic stem cell transplantation (allo-HCT). Researchers recently identified a bacteriophage-derived enzyme called endolysin capable of targeting biofilms formed by Enterococcus faecalis. Their findings offer hope for tailored interventions in allo-HCT.
Published New one-step method to make multiple edits to a cell's genome
(via sciencedaily.com) Original source A team of scientists have developed a new method that enables them to make precise edits in multiple locations within a cell -- all at once. Using molecules called retrons, they created a tool that can efficiently modify DNA in bacteria, yeast, and human cells.
Published The dawn of the Antarctic ice sheets
(via sciencedaily.com) Original source In recent years global warming has left its mark on the Antarctic ice sheets. The 'eternal' ice in Antarctica is melting faster than previously assumed, particularly in West Antarctica more than East Antarctica. The root for this could lie in its formation, as an international research team has now discovered: sediment samples from drill cores combined with complex climate and ice-sheet modelling show that permanent glaciation of Antarctica began around 34 million years ago -- but did not encompass the entire continent as previously assumed, but rather was confined to the eastern region of the continent (East Antarctica).
Published Not so selfish after all: Viruses use freeloading genes as weapons
(via sciencedaily.com) Original source Certain pieces of DNA have been labeled as 'selfish genetic elements' due to notions that they don't contribute to a host organism's survival. Instead, researchers have now discovered that these elements have been weaponized and play a crucial role by cutting off a competitor's ability to reproduce.
Published Researchers uncover key mechanisms in chromosome structure development
(via sciencedaily.com) Original source Researchers are making strides in understanding how chromosome structures change throughout the cell's life cycle.
Published Mighty floods of the Nile River during warmer and wetter climates
(via sciencedaily.com) Original source Global warming as well as recent droughts and floods threaten large populations along the Nile Valley. Sediment cores off the Nile mouth reveal insights into the effects and causes of heavy rainfall episodes about 9,000 years ago. That will help to prepare for weather extremes in a changing climate.
Published A new breakthrough in understanding regeneration in a marine worm
(via sciencedaily.com) Original source The sea worm Platynereis dumerilii is only a few centimeters long but has a remarkable ability: in just a few days, it can regenerate entire parts of its body after an injury or amputation. By focusing more specifically on the mechanisms at play in the regeneration of this worm's tail, a research team has observed that gut cells play a role in the regeneration of the intestine as well as other tissues such as muscle and epidermis.
Published Research shows how RNA 'junk' controls our genes
(via sciencedaily.com) Original source Researchers have made a significant advance in understanding how genes are controlled in living organisms. The new study focuses on critical snippets of RNA in the tiny, transparent roundworm Caenorhabditis elegans (C. elegans). The study provides a detailed map of the 3'UTR regions of RNA in C. elegans. 3'UTRs (untranslated regions) are segments of RNA involved in gene regulation.
Published Researchers thwart resistant bacteria's strategy
(via sciencedaily.com) Original source Bacteria are experts at evolving resistance to antibiotics. One resistance strategy is to cover their cell walls in sticky and gooey biofilm that antibiotics cannot penetrate. A new discovery could put a stop to this strategy.
Published The evidence is mounting: humans were responsible for the extinction of large mammals
(via sciencedaily.com) Original source Human hunting, not climate change, played a decisive role in the extinction of large mammals over the last 50,000 years. This conclusion comes from researchers who reviewed over 300 scientific articles from many different fields of research.
Published Investigating newly discovered hydrothermal vents at depths of 3,000 meters off Svalbard
(via sciencedaily.com) Original source Hydrothermal vents can be found around the world at the junctions of drifting tectonic plates. But there are many hydrothermal fields still to be discovered. During a 2022 expedition of the MARIA S. MERIAN, the first field of hydrothermal vents on the 500-kilometer-long Knipovich Ridge off the coast of Svalbard was discovered.
Published New, holistic way to teach synthetic biology
(via sciencedaily.com) Original source Synthetic biology combines principles from science, engineering and social science, creating emerging technologies such as alternative meats and mRNA vaccines; Deconstructing synthetic biology across scales gives rise to new approach to uniting traditional disciplines; Case studies offer a modular, accessible approach to teaching at different institutions.
Published From takeoff to flight, the wiring of a fly's nervous system is mapped
(via sciencedaily.com) Original source Although a fly's motor neurons are few, it performs remarkable aerial and terrestrial feats. A wiring diagram recently created of the motor circuits in the central nervous system of the fruit fly is providing detailed information on how the nerve coordination of leg movements differs from that controlling the wings. Such studies reveal the unexpected complexity of the fly's tiny motor system. They also advance the understanding of how the central nervous system in animals coordinates individual muscles to carry out a variety of behaviors.
Published Cell division: Before commitment, a very long engagement
(via sciencedaily.com) Original source Before a cell commits fully to the process of dividing itself into two new cells, it may ensure the appropriateness of its commitment by staying for many hours -- sometimes more than a day -- in a reversible intermediate state, according to a new discovery. Their revelation of this fundamental feature of biology includes details of its mechanisms and dynamics, which may inform the development of future therapies targeting cancers and other diseases.
Published The on-and-off affair in DNA
(via sciencedaily.com) Original source Researchers have discovered that in thale cresses histone H3 lysine-9 (H3K9) methylation, conventionally thought to be a mark of turning off gene transcription, can also turn on gene expression via the interactions of two other proteins and histone marks. The molecular mechanisms demonstrate that rather than functioning as a simple 'off switch,' H3K9 methylation is more like a 'dimmer switch' that fine-tunes DNA transcription. The discovery suggests there might be similar mechanisms in other organisms, too.
Published Ocean's loss of oxygen caused massive Jurassic extinction: Could it happen again?
(via sciencedaily.com) Original source Researchers have found a chemical clue in Italian limestone that explains a mass extinction of marine life in the Early Jurassic period, 183 million years ago. Volcanic activity pumped out CO2, warming oceans and lowering their oxygen levels. The findings may foretell the impact climate change and oxygen depletion might have on today's oceans.
Published Shocked quartz reveals evidence of historical cosmic airburst
(via sciencedaily.com) Original source Researchers continue to expand the case for the Younger Dryas Impact hypothesis. The idea proposes that a fragmented comet smashed into the Earth's atmosphere 12,800 years ago, causing a widespread climatic shift that, among other things, led to the abrupt reversal of the Earth's warming trend and into an anomalous near-glacial period called the Younger Dryas.
Published Slipping a note to a neighbor: The cellular way
(via sciencedaily.com) Original source Study reveals how drug molecules bind in channels between neighboring cells, changing intercellular communication.
Published Zebrafish reveal how bioelectricity shapes muscle development
(via sciencedaily.com) Original source New research describes how nerve cells and muscle cells communicate through electrical signals during development -- a phenomenon known as bioelectricity. The communication, which takes place via specialized channels between cells, is vital for proper development and behavior. The study identifies specific genes that control the process, and pins down what happens when it goes wrong. The finding offers clues to the genetic origins of muscle disorders in humans.