Posts Tagged ‘proteins’
Glow-In-The-Dark Cats Could Provide Answers About AIDS
Infection-fighting proteins called restriction factors, made by both cats and humans, are powerless against their respective versions of AIDS. But monkey versions of restriction factors, like the ones produced by the gene from the rhesus macaque, are able to fight HIV and FIV, as the viruses' counter-weapons are designed to fight against human or cat proteins.
The team of American and Japanese scientists injected the antiviral gene and the GFP gene into feline eggs. Almost all of the offspring from these modified eggs had the restriction factor genes, with both fluorescent and AIDS-fighting proteins made throughout their bodies. Cells taken from the animals were found to be resistant to FIV, and the team plans to eventually expose the cats themselves to the virus to see if the restriction factors will protect them. Proof that these genes can protect cats from feline AIDS would be a huge step towards figuring out how to protect humans and prevent HIV.
[BBC]
This Worm Is the First Animal Engineered to Produce Biological Blocks Not Found in Nature
Meet the 21st amino acid
A quick biology primer, just in case high school biology isn't so fresh. DNA is of course the blueprint for all of our biological stuff. It gives instructions on how the amino acids should arrange themselves into proteins, which pick up the heavy lifting of life from there. There are just 20 amino acids, arranged in different combinations, that are encoded in the genome.
The Cambridge team has created nematode worms that generate a 21st, never before seen amino acid. That’s big, because it basically enables a new resolution in genetic manipulation, a kind of “atom-by-atom control” over biological molecules, as one biologist put it to the BBC.
The artificial protein produced by their artificially enhanced nematodes simply contains a fluorescent dye that glows red under UV light--a test to ensure that their genetic manipulation worked. But ostensibly scientists could do all kinds of things with this technique by producing all kinds of novel amino acids and proteins. Unlike an artificial recreation of something natural--something akin to the Venter Institute’s --these nematodes represent that creation of something wholly new.
Keep an eye on this story. It’s bursting with potential for mind-blowing scientific innovation and chilling sci-fi screenplays.
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Next-Generation Gelatin Could be Derived from Humans Instead of Animals
Mmmmmmm
Gelatin is used as a gelling agent in all kinds of things and is generally derived from the collagen in animal bones and skin (particularly cows and pigs). Broken down, it’s just a mixture of peptides and proteins. But it’s still derived from animals, which means there is a risk, however slight, that it could provoke immune system responses in humans or carry infectious diseases. Moreover, animal gelatin can be inconsistent from batch to batch, giving headaches to quality control managers at production plants. And it's not vegetarian.
As such, scientists have tried all kinds of ways to create a better gelatin, and they think they may have found it, right here in us. To create the human-derived gelatin, human genes are inserted into yeast strains that are tuned to produce gelatin in specific, controlled ways. That creates for a more consistent gelatin--and also a twinge of nausea.
Is consuming gelatin derived from human genes some kind of indirect cannibalism, you ask? This may be yet another aspect of the commercial food production chain that the consumer may find it most comfortable to just not think about.
Humans Might Be Able to See the Earth’s Magnetic Field, Like Birds Do
Plenty of animals are known to be able to perceive geomagnetism, using it to navigate and even to . Proteins called cryptochromes, which exist throughout the plant and animal kingdoms, lend several species this ability. The proteins are related to the circadian rhythms of animals and plants, and recent studies have shown it apparently enables light to serve as a geomagnetic locator.
Electrons in cryptochrome molecules come in entangled pairs, and the Earth's magnetic field may cause one of the electrons to wobble. A chemical reaction in response to the wayward electron's altered spin lets birds see magnetic fields in color, according to a theory .
But as far as researchers thought, cryptochrome doesn’t do much to help us orient ourselves, hence why people have to rely on celestial objects, known landmarks and GPS to figure out which way is north.
But a new study suggests the protein could actually express itself in the retina to help detect geomagnetism. Neuroscientists at the University of Massachusetts took a human version of cryptochrome 2, and inserted it into fruit flies that lacked their own version. The fruit flies’ magnetic perception was restored, as reports.
It may not work this way anymore — there are not exactly voluminous reports of humans navigating simply by peering at magnetic field lines — but it could have proved valuable in helping our earliest ancestors navigate, according to researchers who spoke to Wired. Maybe someday researchers will figure out how to exploit this ability once again, and you won’t need that GPS function in your smartphone after all.
The study is reported in today’s issue of Nature Communications.
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Analytical Method Used for Stock Market Helps Pinpoint A Possible Achilles Heel for HIV
HIV's strongest sections could be its greatest weaknesses
HIV has been so difficult to fight in part because it is such an adept mutant. It produces sloppy copies of itself as it replicates, leading to many variations that can withstand drugs and vaccines. And it can produce 100 billion new virus particles every day, as Ed Yong points out over at , which leads to lots and lots of copies. Broad-spectrum drugs or vaccines can’t do very much against a target that morphs so quickly.
But not all the pieces of HIV mutate with such abandon, according to this new study. Some groups of amino acids known as HIV sectors are somewhat less fickle, staying the same while the rest of the virus morphs, according to researchers at the Ragon Institute, a research group bridging MIT, Harvard University and Massachusetts General Hospital. Researchers believe these sites must remain unchanged for the virus to survive and replicate properly.
Researchers led by HIV research pioneer Bruce Walker and MIT chemical engineering professor Arup Chakraborty say this stalwart section of the virus can be turned against it. If the immune system can be trained to attack all the amino acid portions in an HIV sector, the virus will either have to mutate to thwart the attack — thereby undermining its structural integrity, crippling itself — or not mutate, which would render it helpless against drugs or vaccines.
This new targeted approach came from Chakraborty, who thought Walker and colleagues were too limited in their search for solutions, Yong reports. The team turned to random matrix theory, developed in the 1950s to solve nuclear physics problems and which has been used to analyze stocks, as the notes. It can pinpoint correlations between groups of objects, so it can assess how one stock is linked to other groups of stocks, for instance.
Working with HIV proteins taken from a massive database, the team used random matrix theory to analyze HIV’s genetic code and find groups of amino acids whose mutations were coordinated. The segment that mutated the least was dubbed sector 3, on an HIV sector known as Gag, which makes up HIV’s honeycombed inner shell. If the shell mutates, the honeycomb won’t lock together, and the virus would collapse.
“Multiple mutations within this sector are very rare, indicating previously unrecognized multidimensional constraints on HIV evolution,” the authors write in a on their research, which is published this week in the Proceedings of the National Academy of Sciences.
Incidentally, a rare group of patients who can fight HIV without drugs — known as “elite controllers” — use their own immune systems to attack sector 3.
All this suggests a new way of thinking about HIV treatment, the WSJ and others point out. Perhaps HIV drugs should dispense with the full-on assault and opt for targeted strikes instead.
Buoyed by this research, other teams are reportedly already planning new animal studies to test just that.
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New Evidence That Life On Earth Was Forged in Outer Space
Many amino acids, sugars and other molecular building blocks of life are chiral, meaning they have left-handed and right-handed versions. Like your hands, these are mirror opposite pairs that cannot be superimposed on each other. There’s really no reason for one to prevail over the other, but this symmetry breaking happens anyway; life on Earth is largely left-handed (though a recent study suggests its lower forms can be ). In 2009, NASA researchers studied meteorites and found that left-handedness also seems to prevail throughout the cosmos. Last week, they said this quality can be found in an even than they thought.
“This tells us our initial discovery wasn't a fluke; that there really was something going on in the asteroids where these meteorites came from that favors the creation of left-handed amino acids,” said Daniel Glavin of NASA Goddard Space Flight Center.
So something is going on — but what? French scientists may have an answer, which has to do with polarized light. Light oscillates in a given direction, like up or down, left or right. Polarized sunglasses cut down on glare by filtering out horizontally polarized light. But in space, light from distant stars is circularly polarized when it passes through magnetized dust clouds, according to a study published this week in . This circular polarization results in a corkscrew pattern.
Shine those curly rays of light on some water, ammonia and methanol ice, and you’ll get amino acids. Uwe Meierhenrich and colleagues at the University of Nice Sophia Antipolis in France performed just such an experiment with UV light, and they produced a teeny bit more left-handed amino acids than right-handed ones, . This would explain why there are more left-handed amino acids on meteorites, and therefore why life on Earth is so biased to the left.
But the overarching question — why does nature like lefties? — is still up for debate. One study last fall suggested , because they spew a bunch of right-handed electron antineutrinos when they blow up. Further research is still needed to test this theory.
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World’s Largest Video Protein Database Promises Rapid Drug Development
Developed through intensive supercomputer calculations at the Barcelona Supercomputing Center, scientists at the Institute for Research in Biomedicine tapped into the international Protein Data Bank (PDB) to create the new video database. Each of the 1,700 proteins catalogued there is displayed through a series of 10,000 to 100,000 photos, showing how the higher order structures of complex proteins move and change. And while 1,700 proteins out of 40,000 may not seem like a lot, many of the proteins logged in the PDB are highly similar – those 1,700 proteins actually represent something like 40 percent of proteins with a known structure.
What does this mean to those of us who aren't biologists? If there’s a "next big thing" in pharmaceuticals, protein therapies are it. While there are still great strides being made in chemically derived, small-molecule pharmacology, biologic drugs – those derived from biology like protein therapies – open up whole new areas of pharmaceutical exploration. This is the area where the last two decades’ advances in understanding the human genome are just starting to pay off, hopefully leading to treatments for everything from inflammatory diseases to cancer.
But in order to create effective and safe protein therapies, pharmaceutical makers must first understand the structures of the proteins they hope to manipulate. Currently, most drugs are designed around a static picture of proteins, which – like most living things – are anything but. By offering researchers a clearer picture of how protein structures move and change, it should help them more quickly identify new potential therapies and reduce failures in clinical trials.
The 1,700 proteins, now partially available online to researchers worldwide, are just the beginning, as MoDEL will continue to grow as more proteins are better characterized. The researchers behind the project hope to have 80 percent of proteins relevant to treating human diseases available in MoDEL within two to three years.
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