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Categories: Biology: Developmental, Space: The Solar System
Published Scientific definition of a planet says it must orbit our sun; A new proposal would change that
(via sciencedaily.com) Original source The International Astronomical Union defines a planet as a celestial body that orbits the sun, is massive enough that gravity has forced it into a spherical shape, and has cleared away other objects near its orbit around the sun. Scientists now recognize the existence of thousands of planets, but the IAU definition applies only to those within our solar system. The new proposed definition specifies that the body may orbit one or more stars, brown dwarfs or stellar remnants and sets mass limits that should apply to planets everywhere.
Published Muscle machine: How water controls the speed of muscle contraction
(via sciencedaily.com) Original source The flow of water within a muscle fiber may dictate how quickly muscle can contract, according to a new study.
Published Opening the right doors: 'Jumping gene' control mechanisms revealed
(via sciencedaily.com) Original source International joint research led by Akihisa Osakabe and Yoshimasa Takizawa of the University of Tokyo has clarified the molecular mechanisms in thale cresses (Arabidopsis thaliana) by which the DDM1 (Decreased in DNA Methylation 1) protein prevents the transcription of 'jumping genes.' DDM1 makes 'jumping genes' more accessible for transcription-suppressing chemical marks to be deposited. Because a variant of this protein exists in humans, the discovery provides insight into genetic conditions caused by such 'jumping gene' mutations.
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 Mars likely had cold and icy past, new study finds
(via sciencedaily.com) Original source The question of whether Mars ever supported life has captivated the imagination of scientists and the public for decades. Central to the discovery is gaining insight into the past climate of Earth's neighbor: was the planet warm and wet, with seas and rivers much like those found on our own planet? Or was it frigid and icy, and therefore potentially less prone to supporting life as we know it? A new study finds evidence to support the latter by identifying similarities between soils found on Mars and those of Canada's Newfoundland, a cold subarctic climate.
Published The origins of dark comets
(via sciencedaily.com) Original source Up to 60% of near-Earth objects could be dark comets, mysterious asteroids that orbit the sun in our solar system that likely contain or previously contained ice and could have been one route for delivering water to Earth, according to a new study.
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 Strong evidence for intermediate-mass black hole in Omega Centauri
(via sciencedaily.com) Original source Most known black holes are either extremely massive, like the supermassive black holes that lie at the cores of large galaxies, or relatively lightweight, with a mass of under 100 times that of the Sun. Intermediate-mass black holes (IMBHs) are scarce, however, and are considered rare 'missing links' in black hole evolution.
Published Found with Webb: A potentially habitable icy world
(via sciencedaily.com) Original source A international team of astronomers has made an exciting discovery about the temperate exoplanet LHS 1140 b: it could be a promising 'super-Earth' covered in ice or water.
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 Building materials for water-rich planets in the early solar system
(via sciencedaily.com) Original source Age data for certain classes of meteorite have made it possible to gain new findings on the origin of small water-rich astronomical bodies in the early solar system. These planetesimals continually supplied building materials for planets -- also for the Earth, whose original material contained little water. The Earth received its actual water through planetesimals, which emerged at low temperatures in the outer solar system, as shown by computational models carried out by an international research teach with participation by earth scientists.
Published Stench of a gas giant? Nearby exoplanet reeks of rotten eggs, and that's a good thing
(via sciencedaily.com) Original source An exoplanet infamous for its deadly weather has been hiding another bizarre feature -- it reeks of rotten eggs, according to a new study of data from the James Webb Space Telescope.
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 Moon 'swirls' could be magnetized by unseen magmas
(via sciencedaily.com) Original source Mysterious, light-colored swirls on Moon's surface could be rocks magnetized by magma activity underground, laboratory experiments confirm.
Published Machine learning could aid efforts to answer long-standing astrophysical questions
(via sciencedaily.com) Original source Physicists have developed a computer program incorporating machine learning that could help identify blobs of plasma in outer space known as plasmoids. In a novel twist, the program has been trained using simulated data.
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 Organic material from Mars reveals the likely origin of life's building blocks
(via sciencedaily.com) Original source Two samples from Mars together deliver clear evidence of the origin of Martian organic material. The study presents solid evidence for a prediction made over a decade ago that could be key to understanding how organic molecules, the foundation of life, were first formed here on Earth.
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.