https://phys.org/ en-us Phys.org internet news portal provides the latest news on science including: Physics, Nanotechnology, Life Sciences, Space Science, Earth Science, Environment, Health and Medicine. There are many genes, or at least markers of one sort or another within our DNA sequences, that have been associated with height. By some estimates the number could be thousands. However, finding those select genes that have a readily apparent and significant function in height has proven difficult. https://phys.org/news/2022-02-definitive-tall.html Plants & Animals Thu, 03 Feb 2022 09:40:01 EST news563103165 A viable molecular explanation for the origin of compact myelin of vertebrates has been a long time coming. While many invertebrates are certainly capable of wrapping their axons with crude glial extensions, none can manage anything like the massive spiral elaborations of crystalline proteolipid membrane found in the oligodendrocytes of the central nervous system and the Schwann cells of the peripheral. https://phys.org/news/2022-02-myelin-gift-retroviruses.html Evolution Tue, 01 Feb 2022 12:00:02 EST news562936998 The homotrimeric spike glycoprotein (S) from SARS-CoV-2, particularly its S2 subunit, is a fusion protein extraordinaire. It can fuse viral particles to cells and also fuse cells to cells to create multifarious syncytia among different cell phenotypes. Depending on which exact versions are under consideration, the spike can perform these feats via multiple mechanisms acting at both the intracellular and extracellular sides of cell membranes. https://phys.org/news/2022-01-fossils-life-sars-cov-spike-syncytin-.html Cell & Microbiology Thu, 27 Jan 2022 11:30:01 EST news562502839 Cobalt sits in the center of the corrin ring of vitamin B12 and the important cobalamins we derive from it. Perhaps surprisingly, only two of our enzymes bother to use these painfully constructed and meticulously channeled cofactors. Why do our cells go to such great lengths to get a little bit of the cobalt magic, and what catalytic properties might make it so special? https://phys.org/news/2022-01-cobalt-essential-life.html Biochemistry Wed, 26 Jan 2022 11:20:01 EST news562418037 Transposable elements, or jumping genes, are now known to be responsible for many human diseases. Keeping them repressed by methylation, RNA binding, or the attentions of the innate immune system is a full-time jump for cells. https://phys.org/news/2022-01-sars-cov-spike-protein-human-endogenous.html Cell & Microbiology Mon, 24 Jan 2022 09:26:43 EST news562238795 One of the biggest challenges in biology today is to explain the structure of cristae, the inner membranes of mitochondria. An explanation in this case is a set of principles to predict what form the cristae will take after basic metabolic manipulations of the environment the mitochondria are in. These principles will therefore be a description of the true function of mitochondria, something that has so far only been scarcely imagined. https://phys.org/news/2022-01-mitochondria.html Cell & Microbiology Wed, 19 Jan 2022 11:30:02 EST news561811990 Charles Darwin wrote a book called "The Power of Movement in Plants" with his son Francis in which they first identified the root apex as the central command center of plants. In contrast to our own orientation with respect to Earth's gravitational field, Darwin proposed that the root apices represented the anterior cognitive pole of the plant or tree, while the shoot apices represented the posterior pole. In this view, the root apices are solely responsible for identifying and targeting nutrient-rich and toxin-depleted areas of soil in which to grow, while the shoots generate the sexual apparatus for reproduction. https://phys.org/news/2021-02-brains.html Evolution Mon, 15 Feb 2021 09:00:02 EST news532598403 About half of our genome is made up of transposable elements (TEs), also known as transposons. These 'jumping genes' are short stretches of DNA that have the unique ability to duplicate themselves and change their position within our code. While these philanderings play an essential role in the evolution of the species, if unchecked, transposons can wreak havoc on the genome. https://phys.org/news/2021-02-virally-derived-transposons-domesticated-evolve.html Evolution Tue, 09 Feb 2021 07:49:49 EST news532079383 The human cellular kinome contains over 500 kinases, accounting for almost 2% of all our genes. It is currently impossible to gauge the phosphorylation status, or even phosphorylation potential, of the entire proteome of any cell. Mitochondria, on the other hand, use just 25 kinases. Moreover, their entire proteome contains only 1,136 proteins, at least according to the latest version of the Mitocarta Database. https://phys.org/news/2021-02-characterization-full-mitochondrial-kinome.html Biotechnology Mon, 08 Feb 2021 09:10:01 EST news531991072 Although the CRISPR/Cas9 system has seen widespread application in editing the nuclear genome, using it to edit the mitochondrial genome has been problematic. The main hurdles have been a lack of suitable editing sites in the small mtDNA, and the traditional difficulty of importing the guide RNA into the mitochondrial matrix where nucleoids can be accessed. https://phys.org/news/2021-02-crispr-mitochondria-biotech.html Biotechnology Fri, 05 Feb 2021 09:00:01 EST news531731817 In a recent paper in RNA Biology, researchers show that mitochondria translocate their key RNA methyltransferase enzyme, TRMT1, into host cell nuclei in response to neural activity. This subcellular relocalization of key RNA modifiers suggests a new understanding of how neurons plastically reconfigure their nuclei as network dynamics change. https://phys.org/news/2021-02-neural-mitochondrial-rna-nucleus.html Cell & Microbiology Wed, 03 Feb 2021 08:47:57 EST news531564460 3-D printing is a universal process in the sense that pretty much any part that can be drawn up in a CAD program can be printed, at least within a certain resolution. Machining a part on a mill or lathe, while having the advantage of greater accuracy and material options, is a slightly less universal process in that many possible designs that exist in theory could never be machined. A hollow sphere can easily be printed, but a ball could never be milled as a single part into a hollow sphere—unless you happen to have a milling machine tiny enough to fit inside the ball. But what about biological parts, and whole animals? How universal, from a design perspective, is growth? https://phys.org/news/2021-01-chromosomes-evolve-life.html Evolution Wed, 27 Jan 2021 09:10:05 EST news530887290 The Genome in a Box project is the brainchild of researchers Anthony Birnie and Cees Dekker from the Dept. of Bionanoscience at the Delft University of Technology. Their stated goal is to assemble a functioning chromosome from the bottom-up, beginning with the naked DNA. In theory, the raw sequence could be printed in pieces using DNA synthesis machines and then stitched together into one long string with the correct code of the desired chromosome. That would be nearly impossible in practice, at least with our existing technology. There would be no way to keep the fragile strings sorted so that they could be properly joined and folded without error. https://phys.org/news/2021-01-d-creature-chromosomes-ground.html Biotechnology Tue, 26 Jan 2021 08:30:01 EST news530795211 As one wise pundit recently observed, "everybody is a virologist now." For the many people whose interest in biology formerly began and ended with "the mitochondria is the powerhouse of the cell," a second axiom can now be offered, namely, that the virus is the thief of power. In other words, what the mitochondria giveth, the virus taketh away. https://phys.org/news/2021-01-intimate-associations-sars-cov-mitochondria-angles.html Cell & Microbiology Fri, 15 Jan 2021 08:30:01 EST news529916014 There is a sense in which the information encoded in a gene sequence can be represented by two bits per base pair location. The reality, however, is that this is far from a complete description. Although many academically and medically interesting things might be done from the minimalist sequence data, no real organism is going self-construct in developmental real time at this data rate no matter how much parallelism is used. https://phys.org/news/2021-01-situ-sequencing-fully-genome.html Biotechnology Wed, 06 Jan 2021 08:30:01 EST news529139785 Insofar as variants for mitochondrial disease are supposed to be rare in the genome, don't think for even a minute that it can't happen to you. In fact, the closer one looks at the full mitonuclear genomes of normal folks, the more one realizes that no one is actually normal—we are all, shall we say, temporarily asymptomatic. https://phys.org/news/2021-01-full-mitochondrial-ultimate-anticancer-biohack.html Biotechnology Tue, 05 Jan 2021 08:10:05 EST news529054106 Inasmuch as therapeutic options against coronavirus have been focused mainly on blocking the interaction between its spike protein and the ACE2 receptor on host cells, SARS-CoV-2 has several additional critical proteins that could potentially be targeted with drugs that have already been approved for use against other viruses. One of these viral proteins is the main protease (Mpro) that is needed to separate newly minted polypeptides into their functional component parts. https://phys.org/news/2021-01-sars-cov-tracks-blocking-main-protease.html Molecular & Computational biology Mon, 04 Jan 2021 09:20:01 EST news528974251 Everybody loves Neandertals, those big-brained brutes we supposedly outcompeted and ultimately replaced using our sharp tongues and quick, delicate minds. But did we really, though? Is it mathematically possible that we could yet be them, and they us? https://phys.org/news/2020-12-covid-neandertals.html Biotechnology Thu, 24 Dec 2020 09:10:02 EST news528015223 In order for tumors to successfully take hold and spread in the body, they typically must meet several developmental milestones. These include things like suppressing apoptosis, cultivating replication and angiogenesis, weaning from growth factor dependency, becoming less sticky, and becoming more sticky. https://phys.org/news/2020-12-big-kinase-ohmics-drug-discovery.html Biotechnology Wed, 09 Dec 2020 07:17:54 EST news526720670 One of the most hotly contested issues in biology, or at least in mitochondrial biology, is determining which proteins can get into mitochondria. Having this kind of access essentially means a protein maintains a residence in one or more of several distinct mitochondrial compartments. These places include the matrix, the inner membrane, the intermembrane space, the outer membrane and the most nebulous listing of them all—an association with the outer membrane. Typically, it is this location that draws the biggest controversy. https://phys.org/news/2020-12-mitocarta-definitive-elusive-mitochondrial-proteome.html Biotechnology Mon, 07 Dec 2020 09:00:01 EST news526548733 NAD, or nicotinamide adenine dinucleotide, probably needs no introduction. Together with its primary alter-egos NADH, NADP and NADPH, our private suite of pyridine-based nucleotides serve as hydride donors in some 400 enzymatic reactions throughout the body. Beyond these signature dehydrogenase, hydroxylase and reductase reactions, other members of the larger NAD ecosystem function in receptor signaling pathways. Furthermore, the backbone NAD skeleton itself is extensively deployed in DNA repair, and directly consumed as additions to many other important molecules in different organelles. https://phys.org/news/2020-12-nad-nicotine-adenine-dinucleotide-super.html Biotechnology Fri, 04 Dec 2020 07:53:11 EST news526290785 It shouldn't be any secret that mitochondria can make their own fatty acids. The enzymes mitochondria use to do it were discovered decades ago. Unfortunately, only a few individuals among the biologically literate masses have come to appreciate this critical fact about mitochondrial behavior. Perhaps the bigger issue is why mitochondria would go to all the trouble when cells can already make all the fatty acids they need. https://phys.org/news/2020-08-mitochondria-cells-fatty-acid-synthesis.html Cell & Microbiology Mon, 31 Aug 2020 07:37:23 EDT news518078235 Among the most easily recognizable features of any nervous system is the synapse. While the question of how synapses evolved has been a longstanding mystery, it can now largely be solved. In a nutshell, it appears that the synapses between neurons evolved directly from the original cell-to-cell contacts, namely, the adherence junctions and other bonds that linked the primitive epithelial sheets of early multicellular organisms. https://phys.org/news/2020-06-evolution-synapse.html Biotechnology Fri, 26 Jun 2020 09:10:01 EDT news512374495 Transfer of mitochondria between cells is a ubiquitously occurring and now universally known phenomenon. For years, researchers have been serially demonstrating that one particular new cell type can transfer its mitos to yet another particular cell type to achieve some specific metabolic goal essential to survival of the meta-host organism. But what happens when the mitochondria come from the outside world, from other members of your own species, or from a different species altogether? In addressing this very real situation, we first must look at the particulars of how and why mitos are transmitted across cell boundaries in the first place. https://phys.org/news/2020-03-free-range-mitochondria.html Molecular & Computational biology Fri, 27 Mar 2020 12:02:20 EDT news504529334 Deep sea alkaline hydrothermal vents have been theorized to be a place where life could have originated. The elevated temperature, alkaline pH, and unique vent action concentrate minerals and create local energetic gradients that can promote primitive metabolic reactions. Although sometimes overlooked, the extreme hydrostatic pressures found in deep sea vents can also facilitate various kinds of molecular assembly that would not otherwise spontaneously occur at sea level. https://phys.org/news/2020-03-pressure-lessons-cradle-life.html Cell & Microbiology Fri, 20 Mar 2020 08:50:01 EDT news503909685 Mitonuclear interactions are believed to play an important role in the so-called "life history" of Eukaryotic organisms. Unfortunately, no one has come up with any sort of general concrete theory that can predict or even describe these interactions. A recent thematic issue of Philosophical Transaction of the Royal Society comprises a series of articles that attempt the formidable task of linking mitochondrial genotype to phenotype. Of note among them is an article that uses specially crafted populations of fruit flies to explore mitonuclear interactions in life history responses to changes in an organism's environment. https://phys.org/news/2019-12-mitonuclear-interactions-life-history.html Evolution Thu, 19 Dec 2019 07:53:50 EST news495964419 One of the most puzzling aspects of cancer is how cells inevitably manage to reactivate precisely those few genes that can turn them into tumors. One example, discussed at length here yesterday, is the restoration of telomerase or alternative telmore repair enzymes that enable indefinite chromsome replication. Another example is the emergency drafting of backup hexokinases to kick off supplementary glycolysis. https://phys.org/news/2018-06-metabolism-functionthe-extreme-photoreceptors.html Cell & Microbiology Fri, 15 Jun 2018 09:10:06 EDT news448268523 All schoolchildren learn that the difference between eukaryotes and prokaryotes has something to do with a nucleus. This is usually around the same time they learn that the mitochondria is the powerhouse of the cell. The real difference between these two life forms, however, has more to do with how they control the flow of electrons to make their living, i.e., their electron transport chains going from donors to acceptors via redox reactions. https://phys.org/news/2018-05-wisdom-protists-electron-cancer.html Cell & Microbiology Fri, 18 May 2018 09:30:01 EDT news445848676 Humans have 46 chromosomes, and each one is capped at either end by repetitive sequences called telomeres. If you ask a biologist if humans have circular DNA, they are likely to say 'no.' That is because eukaryotic cell nuclei have linear chromosomes, while prokaryotes have circular nucleoids and plasmids. However, biologists also know that most of our cells have mitochondria that do, in fact, retain the circular DNA, the chromosome 'M,' which they inherited from their prokaryotic ancestors. https://phys.org/news/2018-05-mitochondria-art-dna-maintenance.html Biotechnology Fri, 11 May 2018 10:00:01 EDT news445240444 (Phys.org)—Piece by piece, the circuit diagram for electron transport in the mitochondria has come closer to completion. Each new structure obtained for any of the five respiratory complexes further constrains the assembled puzzle. Eventually, big blocks are arranged into their final placements. The exact composition of the biggest block, the so-called megacomplex, has long eluded researchers. Now, after imaging 140 individual subunits down to 3.9 anstrom resolution, the Full Monty has been laid bare. Researchers describe in Cell exactly how the human respiratory megacomplex is put together and appears to function. https://phys.org/news/2017-09-mitochondrial-respiratory-supercomplex-decoded.html Cell & Microbiology Fri, 22 Sep 2017 09:10:01 EDT news425280686