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UMass Amherst Biochemists Trap a Chaperone Machine in Action, Opening Pathway to Possible New Cancer Treatment

By Guest PostJanuary 2, 2013Scienceadp, amino acid chains, anastasia zhuravleva, atp, bacteria, cancer cell, chemical environments, cycle, dnak, drug target, e coli bacteria, Environment, eugenia clerico, folding of proteins, heat shock protein, holding pattern, hsp, hsp70, humans, key step, lila gierasch, massachusetts amherst, mechanism, molecular chaperones, molecular machine, nanofactories, neurodegenerative diseases, nmr methods, nuclear magnetic resonance, origami like, ribosomes, stress, uncontrolled growth, university

AMHERST, Mass. – Molecular chaperones have emerged as exciting new potential drug targets, because scientists want to learn how to stop cancer cells, for example, from using chaperones to enable their uncontrolled growth. Now a team of biochemists at the University of Massachusetts Amherst led by Lila Gierasch have deciphered key steps in the mechanism of the Hsp70 molecular machine by “trapping” this chaperone in action, providing a dynamic snapshot of its mechanism.

She and colleagues describe this work in the current issue of Cell. Gierasch’s research on Hsp70 chaperones is supported by a long-running grant to her lab from NIH’s National Institute for General Medical Sciences. (more…)

Research by CU-Boulder Physicists Creates ‘Recipe Book’ for Building New Materials

By Guest PostJanuary 1, 2013Scienceamherst, bohdan senyuk, China, coffee cup, colloids, colorado boulder, continuously deformed, creation, ivan smalyukh, liquid crystal, liquid crystal displays, materials genome initiative, mathematical theorems, Pennsylvania, president barack obama, qingkun liu, randall kamien, recipe book, robert kusner, sailing he, tiny particle, tom lubensky, topology, university, university of massachusetts, White House, zhejiang university

By showing that tiny particles injected into a liquid crystal medium adhere to existing mathematical theorems, physicists at the University of Colorado Boulder have opened the door for the creation of a host of new materials with properties that do not exist in nature.

The findings show that researchers can create a “recipe book” to build new materials of sorts using topology, a major mathematical field that describes the properties that do not change when an object is stretched, bent or otherwise “continuously deformed.” Published online Dec. 23 in the journal Nature, the study also is the first to experimentally show that some of the most important topological theorems hold up in the real material world, said CU-Boulder physics department Assistant Professor Ivan Smalyukh, a study senior author. (more…)

U of T Researchers Uncover Major Source of Evolutionary Differences among Species

By Guest PostJanuary 1, 2013Nature, Sciencealternative splicing, alzheimer, benjamin blencowe, brain, cancer, chicken, chimpanzee, disease, disease susceptibility, frog, fundamental characteristics, fundamental difference, genetic basis, genetic messages, heart, human, human brain, human diseases, identical, liver, mouse, multiple proteins, nuno barbosa morais, set of genes, species, university of toronto, vertebrate, vertebrate evolution

TORONTO, ON – University of Toronto Faculty of Medicine researchers have uncovered a genetic basis for fundamental differences between humans and other vertebrates that could also help explain why humans are susceptible to diseases not found in other species.

Scientists have wondered why vertebrate species, which look and behave very differently from one another, nevertheless share very similar repertoires of genes. For example, despite obvious physical differences, humans and chimpanzees share a nearly identical set of genes. (more…)

JILA Physicists Achieve Elusive ‘Evaporative Cooling’ of Molecules

By Guest PostDecember 30, 2012Sciencecooling molecules, energetic molecules, evaporative cooling, molecules, reactive molecules

Achieving a goal considered nearly impossible, JILA physicists have chilled a gas of molecules to very low temperatures by adapting the familiar process by which a hot cup of coffee cools. (more…)

Within the Earth, Blobs of Molten Iron on the Move

By Guest PostDecember 29, 2012Scienceamount of iron, boundary zone, interior layer, iron rich blobs, mantle, metal rich blobs, morphological instability, ocean islands, rocky mantle, seismic wave

New research by Yale University scientists suggests an explanation for the amount of iron in the Earth’s largest interior layer, the mantle: migrating “iron-rich blobs” generated by chemical interactions in the zone between the planet’s core and mantle. (more…)

Piranha Kin Wielded Dental Weaponry Even T. Rex Would Have Admired

By Guest PostDecember 27, 2012Nature, Scienceamazon river, american alligator, american university, ancient relative, anecdotes, armored fish, barracuda, bite, bite force, black piranha, blacktip shark, bull shark, c caracharias, c leucas, c limbatus, cairo, carcharodon megalodon, carnivorous fishes, customized force gage, dunkleosteus terrelli, earth, egypt, extinct mega predators, extinct piranhas, fossilized jaw, george washington university, guillermo orti, hammerhead shark, history, hyperbole, jaw forces, jaw muscles, jorge porto, justin grubich, largest piranha, mega bites, megapiranha paranensis, piranha infested waters, piranha like ability, piranhas, prehistoric, s mokarran, serrasalmus rhombeus, skeleton, soft tissue, stephanie crofts, steve huskey, t rex, teeth, tendons, tyrannosaurus rex, university of washington, western kentucky university, whale eating sharks, white sharks

Taking into consideration its size, an ancient relative of piranhas weighing about 20 pounds delivered a bite with a force more fierce than prehistoric whale-eating sharks, the four-ton ocean-dwelling Dunkleosteus terrelli and – even – Tyrannosaurus rex.

Besides the force of the bite, Megapiranha paranensis appears to have had teeth capable of shearing through soft tissue the way today’s piranhas do, while also being able to pierce thick shells and crack armoring and bones, according to Stephanie Crofts, a University of Washington doctoral student in biology. (more…)

Blades and Clades: Why Some Grasses Got Better Photosynthesis

By Guest PostDecember 25, 2012Scienceagriculture, anatomical difference, anatomical traits, ancestral state reconstruction, atmospheric co2, bep clade, blades, bundle sheath cells, c3, c4, c4 evolution, cellular anatomy, clades, david chatelet, dry condition, erika edwards, evolutionary time scale, evolutionary tree, genetic data, grasses, laura garrison, lineage, mesophyll cells, pacmad clade, pascal antoine christin, photosynthesis, physiology

Two groups — clades — of grasses that once had a common ancestry diverged. The PACMAD clade was predisposed to evolve a more efficient “C4” means of photosynthesis than grasses in the BEP clade. In a new study in the Proceedings of the National Academy of Sciences, a Brown-led team pinpoints the anatomical differences between the clades that led to the PACMAD’s tendency toward C4.

PROVIDENCE, R.I. [Brown University] — Even on the evolutionary time scale of tens of millions of years there is such a thing as being in the right shape at the right time. An anatomical difference in the ability to seize the moment, according to a study led by Brown University biologists, explains why more species in one broad group, or clade, of grasses evolved a more efficient means of photosynthesis than species in another clade. (more…)

Study Reveals New Factor that could Limit the Life of Hybrid and Electric Car Batteries

By Guest PostDecember 25, 2012Science, Technologyautomotive industry, battery electrodes, battery life, bharat bhushan, car batteries, cathode, current collector, electric car batteries, electrical system, electrodes, electron transfer, factor, giorgio rizzoni, gregory downing, hybrid, hybrid electric cars, life, limit, lithium ion batteries, ndp, neutron depth profiling, ohio state university, set of particles, sheet of copper, shrikant nagpure, suresh babu, yann guezennec

COLUMBUS, Ohio – A new study of the batteries commonly used in hybrid and electric-only cars has revealed an unexpected factor that could limit the performance of batteries currently on the road.

Researchers led by Ohio State University engineers examined used car batteries and discovered that over time lithium accumulates beyond the battery electrodes – in the “current collector,” a sheet of copper which facilitates electron transfer between the electrodes and the car’s electrical system. (more…)

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