Biology and Medicine

Advances in the investigation of the physical universe we live in.
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Typhoon
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Re: Biology and Medicine

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Wired | It’s (Almost) Alive!
Three billion years after inanimate chemistry first became animate life, a newly synthesized laboratory compound is behaving in uncannily lifelike ways.

The particles aren’t truly alive — but they’re not far off, either. Exposed to light and fed by chemicals, they form crystals that move, break apart and form again.
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Re: Biology and Medicine

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Re: Biology and Medicine

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.


.. researchers have identified a mutation in a critical human gene as the source of several distinctive traits that make East Asians different from other races.


The traits – thicker hair shafts, a greater number of sweat glands, characteristically identified teeth and smaller breasts – are the result of a gene mutation that occurred some 35,000 years ago


The discovery explains a crucial juncture in the evolution of East Asians. But the method can also be applied to some 400 other sites on the human genome. The DNA changes at these sites, researchers believe, mark the turning points in recent human evolution as the populations on each continent diverged from each other.

The first of those sites to be studied contains the gene known as EDAR. Africans and Europeans carry the standard version of the gene, but in most East Asians one of the DNA units has mutated.

more @ link

.


interesting .. wonder how that mutation effects men

"remark edited by Azari"


.
Last edited by Heracleum Persicum on Fri Feb 15, 2013 8:55 pm, edited 1 time in total.
noddy
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Re: Biology and Medicine

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i take it you have personally researched lots of asian peni or is this anecdotal experience ?
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Re: Biology and Medicine

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Doesn't matter. Your genome will be as mutable as the headliner on a 78 Buick, within not much more than 10 years. Just chill. You are all modable.
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Re: Biology and Medicine

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ill end up with multiple peni's of various sizes each of which shoots an addictive intoxicant... blink.. ermm. nevermind me. ermm yes.
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Bees use Karma to choose which flowers to pollinate

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Bees use the 'force' to choose the best flowers, study finds

Bees can alter the electrical charge of the flowers they touch. A new study finds that bees use these electrical cues to help them choose flowers with the most nectar and pollen.

By Pete Spotts, Staff writer / February 22, 2013

Bees learn to use electrical clues to choose which flower is the most promising target, according to a new study.

Vasily Fedosenko/Reuters/File
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If you're a bee having a hard time finding that flower trying to tell you it's loaded with nectar and pollen, use the force, bee, use the force.

In Pictures: Busy bees

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For the first time, scientists have demonstrated that the interaction of charges that can build up naturally on bees and plants plays a role in helping the insects find the best flowers to nourish themselves and the hive.

Bees have long been known to use color, shape, patterns, and odor to identify their their floral targets. The new study, conducted by researchers at the University of Bristol in Britain, suggests that bees also use electrical cues. Based on the results, the researchers suggest that if bees approach a flower and sense a disturbance in the "force," they know another bee has beat them to the blossom.

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From a bee's perspective, electrical cues are another tool that enables more-efficient foraging. The flower also benefits, according to University of Bristol biologist Daniel Robert, who oversaw the study.

"The last thing a flower wants is to attract a bee and then fail to provide nectar," he said in a prepared statement. Bees quickly learn which flowers are productive and which aren't. The ones that aren't are less likely to get visits and have their pollen spread to other flowers for reproduction. The electrical cues they receive from the flowers may represent a "come back later" signal.

Bees' ability to sense and respond to plants' electrical fields "is a remarkable finding, " says Mark Winston, a biologist at Simon Fraser University in Burnaby, B.C., and the author of a book on bee biology.

It represents another method "by which bees perceive the world around them and it adds another wonderful story that continues to deepen our understanding the co-evolved relationship between bees and flowers," he says.

For 30 years, some researchers have posited that electrostatic charges that can build up on bees play a role in the bees taking up and transporting pollen – a kind of small-scale static cling. They also found that the voltage associated with a flower changes as it's pollinated.

But the experiments by Dr. Robert and colleagues suggest that electricity represents a medium for conveying information between flower and bee before the bee lands.

Previous studies had indicated that bees carry a positive electrical charge with voltages that in some cases can reach as high as 200 volts. They build up the charge as they fly. With their roots in the earth, plants tend to carry a negative charge.
http://www.csmonitor.com/Science/2013/0 ... tudy-finds
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Re: Biology and Medicine

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Brain Scans Show how Evolution Shaped Human Brain into Being Unique

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Affirunisa Kankudti
First Posted: Feb 23, 2013 02:38 PM EST
brain
(Photo : REUTERS/Brian Snyder )

Human brain is unique in the way it processes information and has had significant changes in its structure since humans' split from monkeys some 25 million years ago. Now, brain scans have shown how significant these structural changes are in giving human brains unique networks to process and store vast amount of information.

In the study, researchers used functional Magnetic Resonance Imaging to assess levels of activity in different regions of the brain in both monkeys and humans. The study results found that although human and monkey brain had similar structures, there were at least two functional networks in the cerebral cortex of the brains of humans that were unique and not found in monkeys meaning that these networks developed as humans strayed away from their primate relatives.

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"We did functional brain scans in humans and rhesus monkeys at rest and while watching a movie to compare both the place and the function of cortical brain networks. Even at rest, the brain is very active. Different brain areas that are active simultaneously during rest form so-called 'resting state' networks. For the most part, these resting state networks in humans and monkeys are surprisingly similar, but we found two networks unique to humans and one unique network in the monkey," Professor Wim Vanduffel, Neurophysiology Research Group Faculty of Medicine, KU Leuven, an one of the study authors.

The cerebral cortex, also called the gray region of the brain, is a region where most of the information is processed.

Vanduffel said that when we watch movies, out brain is actively trying to make sense of the visual and auditory signals. And, the way human brain reacts to these signals is totally different from a monkey's reaction. He added that brain structures that are present to accommodate all this information is unique to humans and that the monkey brain has got no such feature either in the cortex or elsewhere in the brain.

"Our unique brain areas are primarily located high at the back and at the front of the cortex and are probably related to specific human cognitive abilities, such as human-specific intelligence," he concluded, according to a news release.

The study is published in The Journal of Neuroscience.
http://www.counselheal.com/articles/403 ... -being.htm
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Re: Biology and Medicine

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RSC | New antibiotics: what's the hold up?
What’s so difficult is that bacteria are completely unlike the human cells that most drugs target. The cells in our bodies live in gated communities, surrounded by their friends and relatives. They have their food delivered to them, they have their waste hauled away, and they have a standing army ready to protect them. This has allowed them to devote themselves to the specialisation that keeps us all walking around. But bacteria are generalists. They have to be, living in a constant Hobbesian war of all against all. They’re fighting for their food, for living space, and against constant attempts by their neighbours to kill them off.

Those neighbours include us. We’ve exerted the most concentrated Darwinian selection pressure we could manage on the pathogenic strains. And that leaves the surviving bacteria equipped with a wide (and constantly evolving) array of defensive measures against just the sorts of attacks we’d like to mount against them.
This all means, it’s sad to say, that the limiting factor in antibiotic drug discovery probably isn’t the amount of money to be made at it. That’s too bad. Money’s a factor that could be adjusted by regulatory agencies, governments, and foundations. But no amount of cash will keep resistant bacteria from being the hard targets they are.
Nature may take case of the boomer demographic bulge in it's usual indifferent manner . . .
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Re: Biology and Medicine

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>>care.......'>.......
She irons her jeans, she's evil.........
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Re: Biology and Medicine

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Typhoon wrote:RSC | New antibiotics: what's the hold up?
What’s so difficult is that bacteria are completely unlike the human cells that most drugs target. The cells in our bodies live in gated communities, surrounded by their friends and relatives. They have their food delivered to them, they have their waste hauled away, and they have a standing army ready to protect them. This has allowed them to devote themselves to the specialisation that keeps us all walking around. But bacteria are generalists. They have to be, living in a constant Hobbesian war of all against all. They’re fighting for their food, for living space, and against constant attempts by their neighbours to kill them off.

Those neighbours include us. We’ve exerted the most concentrated Darwinian selection pressure we could manage on the pathogenic strains. And that leaves the surviving bacteria equipped with a wide (and constantly evolving) array of defensive measures against just the sorts of attacks we’d like to mount against them.
This all means, it’s sad to say, that the limiting factor in antibiotic drug discovery probably isn’t the amount of money to be made at it. That’s too bad. Money’s a factor that could be adjusted by regulatory agencies, governments, and foundations. But no amount of cash will keep resistant bacteria from being the hard targets they are.
Nature may take case of the boomer demographic bulge in it's usual indifferent manner . . .
Yes, I'll believe that when there's an actual burning need, hundreds of billions invested and nothing to show for it. All I see is one biologist complaining that biology is hard.
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Re: Biology and Medicine

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Taboo wrote:
Typhoon wrote:RSC | New antibiotics: what's the hold up?
What’s so difficult is that bacteria are completely unlike the human cells that most drugs target. The cells in our bodies live in gated communities, surrounded by their friends and relatives. They have their food delivered to them, they have their waste hauled away, and they have a standing army ready to protect them. This has allowed them to devote themselves to the specialisation that keeps us all walking around. But bacteria are generalists. They have to be, living in a constant Hobbesian war of all against all. They’re fighting for their food, for living space, and against constant attempts by their neighbours to kill them off.

Those neighbours include us. We’ve exerted the most concentrated Darwinian selection pressure we could manage on the pathogenic strains. And that leaves the surviving bacteria equipped with a wide (and constantly evolving) array of defensive measures against just the sorts of attacks we’d like to mount against them.
This all means, it’s sad to say, that the limiting factor in antibiotic drug discovery probably isn’t the amount of money to be made at it. That’s too bad. Money’s a factor that could be adjusted by regulatory agencies, governments, and foundations. But no amount of cash will keep resistant bacteria from being the hard targets they are.
Nature may take case of the boomer demographic bulge in it's usual indifferent manner . . .
Yes, I'll believe that when there's an actual burning need, hundreds of billions invested and nothing to show for it. All I see is one biologist complaining that biology is hard.
Biology is hard. Especially with regards to new drug development:

Image
The first thing to note is of those drugs which pass animal tests, 94% will fail during human clinical trials stages (Phases 1 – 3)*.

*number of drugs which have passed Phase 3 clinical trials ÷ number of drugs which have passed just animal tests = 1.2 ÷ 19.4 = 6.2% of drugs which reach Phase 1 trials are eliminated by Phase 1-3 clinical trials. 100 – 6.2 = 93.8% fail.

Consider that of all the drugs which pass Phase 1 clinical trials in humans, 86% will fail in later stage human trials**.

**number of drugs which have passed Phase 3 clinical trials ÷ number of drugs which have passed Phase 1 trials = 1.2 ÷ / 8.6 = 14% of drugs which pass Phase 1 trials are eliminated by Phase 2-3 clinical trials. 100 – 14 = 86% fail.
As some wag noted, "If the goal had been to cure cancer in mice, then we would have succeeded decades ago."
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Re: Biology and Medicine

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Bras do harm rather than good. Lead to more breast sagging and back pain over long term.
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Panspermia, again

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Moore’s Law and the Origin of Life

Here’s an interesting idea. Moore’s Law states that the number of transistors on an integrated circuit doubles every two years or so. That has produced an exponential increase in the number of transistors on microchips and continues to do so.

But if an observer today was to measure this rate of increase, it would be straightforward to extrapolate backwards and work out when the number of transistors on a chip was zero. In other words, the date when microchips were first developed in the 1960s.

A similar process works with scientific publications. Between 1990 and 1960, they doubled in number every 15 years or so. Extrapolating this backwards gives the origin of scientific publication as 1710, about the time of Isaac Newton.

Today, Alexei Sharov at the National Institute on Ageing in Baltimore and his mate Richard Gordon at the Gulf Specimen Marine Laboratory in Florida, have taken a similar to complexity and life.

These guys argue that it’s possible to measure the complexity of life and the rate at which it has increased from prokaryotes to eukaryotes to more complex creatures such as worms, fish and finally mammals. That produces a clear exponential increase identical to that behind Moore’s Law although in this case the doubling time is 376 million years rather than two years.

That raises an interesting question. What happens if you extrapolate backwards to the point of no complexity–the origin of life?

Sharov and Gordon say that the evidence by this measure is clear. “Linear regression of genetic complexity (on a log scale) extrapolated back to just one base pair suggests the time of the origin of life = 9.7 ± 2.5 billion years ago,” they say.

Image

And since the Earth is only 4.5 billion years old, that raises a whole series of other questions. Not least of these is how and where did life begin.

Of course, there are many points to debate in this analysis. The nature of evolution is filled with subtleties that most biologists would agree we do not yet fully understand.

For example, is it reasonable to think that the complexity of life has increased at the same rate throughout Earth’s history? Perhaps the early steps in the origin of life created complexity much more quickly than evolution does now, which will allow the timescale to be squeezed into the lifespan of the Earth.

Sharov and Gorden reject this argument saying that it is suspiciously similar to arguments that squeeze the origin of life into the timespan outlined in the biblical Book of Genesis.

Let’s suppose for a minute that these guys are correct and ask about the implications of the idea. They say there is good evidence that bacterial spores can be rejuvenated after many millions of years, perhaps stored in ice.

They also point out that astronomers believe that the Sun formed from the remnants of an earlier star, so it would be no surprise that life from this period might be preserved in the gas, dust and ice clouds that remained. By this way of thinking, life on Earth is a continuation of a process that began many billions of years earlier around our star’s forerunner.

Sharov and Gordon say their interpretation also explains the Fermi paradox, which raises the question that if the universe is filled with intelligent life, why can’t we see evidence of it.

However, if life takes 10 billion years to evolve to the level of complexity associated with humans, then we may be among the first, if not the first, intelligent civilisation in our galaxy. And this is the reason why when we gaze into space, we do not yet see signs of other intelligent species.

There’s no question that this is a controversial idea that will ruffle more than a few feathers amongst evolutionary theorists.

But it is also provocative, interesting and exciting. All the more reason to debate it in detail.

http://www.technologyreview.com/view/51 ... n-of-life/
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Re: Biology and Medicine

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The bit that with the fit to the the data points is interesting.

The extrapolation back in time is wholly speculative: is there any reason to think this log-scale fit applies to pre-life at the molecular scale?
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Re: Biology and Medicine

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I wonder if Wright's Law, rather than Moore's Law, were used the predicted time of life's origin would be closer to 4 billion years. I suspect that it would.

Wright's Law, formulated in 1936 by Theodore P. Wright, states that progress increases with experience — specifically, that each percent increase in cumulative production in a given industry results in a fixed percentage improvement in production efficiency.

The cumulative number of organisms on Earth would have shot up faster than the cumulative time of life on Earth. So, Moore's Law could underestimate the rate of change in the first 100s of millions of years of life on Earth if a more accurate model is Wright's Law.
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Entropy and Intelligence

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PRL | Model Suggests Link between Intelligence and Entropy
Dynamical systems that maximize their future possibilities behave in surprisingly “intelligent” ways.
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Re: Entropy and Intelligence

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Typhoon wrote:PRL | Model Suggests Link between Intelligence and Entropy
Dynamical systems that maximize their future possibilities behave in surprisingly “intelligent” ways.
It sounds like complicated dynamical systems work like a search engine; in a similar way to how PageRank ranks websites based on giving a website a higher value the higher the number of sites linking to it (directly or indirectly), nature seems to follow a path where states at a given point in time are given a higher probability the higher the number of future possible states from that path. So the authors more or less conceptualize nature as being a giant search engine.
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Re: Biology and Medicine

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Typhoon wrote:
Taboo wrote:
Typhoon wrote:RSC | New antibiotics: what's the hold up?
What’s so difficult is that bacteria are completely unlike the human cells that most drugs target. The cells in our bodies live in gated communities, surrounded by their friends and relatives. They have their food delivered to them, they have their waste hauled away, and they have a standing army ready to protect them. This has allowed them to devote themselves to the specialisation that keeps us all walking around. But bacteria are generalists. They have to be, living in a constant Hobbesian war of all against all. They’re fighting for their food, for living space, and against constant attempts by their neighbours to kill them off.

Those neighbours include us. We’ve exerted the most concentrated Darwinian selection pressure we could manage on the pathogenic strains. And that leaves the surviving bacteria equipped with a wide (and constantly evolving) array of defensive measures against just the sorts of attacks we’d like to mount against them.
This all means, it’s sad to say, that the limiting factor in antibiotic drug discovery probably isn’t the amount of money to be made at it. That’s too bad. Money’s a factor that could be adjusted by regulatory agencies, governments, and foundations. But no amount of cash will keep resistant bacteria from being the hard targets they are.
Nature may take case of the boomer demographic bulge in it's usual indifferent manner . . .
Yes, I'll believe that when there's an actual burning need, hundreds of billions invested and nothing to show for it. All I see is one biologist complaining that biology is hard.
Biology is hard. Especially with regards to new drug development:

As some wag noted, "If the goal had been to cure cancer in mice, then we would have succeeded decades ago."
Agreed. Nonetheless, scientist are Fighting Bacteria With New Genre of Antibodies, and report making a Significant Step Forward in Combating Antibiotic Resistance
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Re: Biology and Medicine

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cultivate a white rose
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Re: Biology and Medicine

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They caught Marcus! :o
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Re: Biology and Medicine

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Cockatoos solve 5 step puzzle to get treat

In recent years, more and more evidence is coming out that some birds (it seems particularly corvids, parrots and cockatoos) are quite smart.
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Why birds are smart

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Bird Brain? Birds and Humans Have Similar Brain Wiring
July 17, 2013

A researcher from Imperial College London and his colleagues have developed for the first time a map of a typical bird brain, showing how different regions are connected together to process information. By comparing it to brain diagrams for different mammals such as humans, the team discovered that areas important for high-level cognition such as long-term memory and problem solving are wired up to other regions of the brain in a similar way. This is despite the fact that both mammal and bird brains have been evolving down separate paths over hundreds of millions of years.

The team suggest that evolution has discovered a common blueprint for high-level cognition in brain development.

Birds have been shown in previous studies to possess a range of skills such as a capacity for complex social reasoning, an ability to problem solve and some have even demonstrated the capability to craft and use tools.

Professor Murray Shanahan, author of the study from the Department of Computing at Imperial College London, says: "Birds have been evolving separately from mammals for around 300 million years, so it is hardly surprising that under a microscope the brain of a bird looks quite different from a mammal. Yet, birds have been shown to be remarkably intelligent in a similar way to mammals such as humans and monkeys. Our study demonstrates that by looking at brains that are least like our own, yet still capable of generating intelligent behaviour, we can determine the basic principles governing the way brains work."

The team developed their map by analysing 34 studies of the anatomy of the pigeon brain, which is typical for a bird. They focussed on areas called 'hub nodes', which are regions of the brain that are major centres for processing information and are important for high level cognition.

In particular, they looked at the hippocampus, which is important for navigation and long-term memory in both birds and mammals. They found that these hub nodes had very dense connections to other parts of the brain in both kinds of animal, suggesting they function in a similar way.

They also compared the prefrontal cortex in mammals, which is important for complex thought such as decision making, with the nidopallium caudolaterale, which has a similar role in birds. They discovered that despite both hub nodes having evolved differently, the way they are wired up within the brain looks similar.

The long-term goal of the team is to use the information generated from the wiring diagram to build computer models that mimic the way that animal brains function, which would be used to control a robot.

http://www.sciencedaily.com/releases/20 ... 095336.htm
This gives some substance to one of my favourite fantasies: if dinosaurs had not become extinct 65 million years ago, the intelligent species on Earth might be greenish coloured and have scales (or feathers?) instead of skin like us. The fact that birds seem to be descendant of dinosaurs would imply that dinosaurs would have the same mental skills as birds, and could have evolved to become self-aware.
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Re: Biology and Medicine

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Giant Virus

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Scientists find new giant Pandoravirus unlike any known
Posted Jul 20, 2013 by JohnThomas Didymus

Scientists have discovered a new genus of viruses, the biggest ever. Pandoraviruses are tens to hundreds of times the size of other known viruses. The weirdest thing about them is that 93 percent of their genes are unlike those of other known viruses

For all that scientists can tell from their genes, they just landed from planet Mars.

Pandoraviruses have massive DNA consisting of over 2,500 genes compared with about 13 genes found in influenza viruses. Measuring about one micrometer in length, pandoraviruses are tens to hundreds of times bigger than other viruses.

Image

The discovery of the new genus follows the surprising discovery of viruses of the genus Mimivirus, about 0.7 micron, and Megavirus chilensis. Time reports that according to Chantal Abergel, one of the authors of the new study, when scientists first discovered giant viruses they were so baffled that they simply tagged them NLF, that is, "New Life Form."

According to the authors Claverie, Abergel et al., in a paper entitled "Pandoraviruses: Amoeba Viruses with Genomes Up to 2.5 Mb Reaching That of Parasitic Eukaryotes," published in journal Science, July 19: "Ten years ago, the discovery of Mimivirus, a virus infecting Acanthamoeba, initiated a reappraisal of the upper limits of the viral world, both in terms of particle size (>0.7 micrometers) and genome complexity (>1000 genes)... We report the isolation of two giant viruses, one off the coast of central Chile, the other from a freshwater pond near Melbourne (Australia), without morphological or genomic resemblance to any previously defined virus families... These viruses are the first members of the proposed 'Pandoravirus' genus, a term reflecting their lack of similarity with previously described microorganisms and the surprises expected from their future study."

Biologists have always viewed viruses with suspicion and puzzlement as the weirdos of the biological scheme of things. What do you call a strand of DNA-in-protein-envelope that must hijack the cellular apparatus of other living things to perform even the most basic of life defining tasks such as reproduction? Then Pandoravirus appears with a new set of riddles to add to the unsolved: Expressing the confusion biologists have always felt about the status of viruses in the hierarchy of life to which pandoraviruses now add new complications, Abergel said: "The question is whether Pandoravirus might have evolved from a bacterium. And the answer is, maybe it could. We don’t really understand where viruses come from, and we don’t really understand what they are."

When scientists finally overcame their first shock at the discovery of the first giant viruses and convinced themselves that the weird "Martian" NLFs were actually giant viruses, they began a search for others.

Study co-author Jean-Michel Claverie, a microbiologist at Aix-Marseille Universite in France and Chantal Abergel, also of Aix-Marseille Universite, joined the search for other new giant viruses in amoeba rich water sediments where the first big viruses were found.

They eventually found two species of genus Pandoravirus which are amoeba parasites: Pandoravirus salinus in Chile's Tunquen River, and Pandoravirus dulcis from a freshwater pond near Melbourne in Australia.

Claverie said: "We have been thinking deeply into the limits of viruses, and this is why we're open more than other labs to finding exotic things—we push the envelope of what we would consider possible."

According to the study authors: "Finding such a new type of virus that is so different happens once every 50 years—it's a major discovery."

The authors pointed out that the reason why pandoraviruses remained unknown for so long could be that scientists, working on certain assumptions about viruses, missed them. Apart from the fact that most viruses are much smaller, pandoraviruses lack key morphological features characteristic of other viruses which means that a researcher who chances on them would tend to assume they are some kind of bacterium. National Geographic reports the authors said: "When people look into cells and when they see things that don't have the right dimension or don't have regular assets or geometries, they don't think of viruses—they think its some kind of bacteria."

They explained further that scientists who discovered them earlier might have ignored them when they failed to cultivate them in the lab: It is known that many naturally occurring bacteria cannot be grown in the lab.

What is probably most remarkable about pandoraviruses is that they share very little in common with other viruses. Not only is their mode of reproduction unusual, more than 93 percent of their 2,500 genes have no evolutionary links in nature: The startling implication of this is that pandoraviruses could have dropped recently from Mars for all scientists can tell at the moment.

The startling novelty has lead to the suggestion that they represent a "fourth domain" of life in addition to the three previously recognized: bacteria, archaea (formerly grouped together as prokaryotae) and eukaryotae to which humans also belong.

Claverie and Abergel explain: "The lack of similarity of most of their genes with other life forms might be an indication that they originated from a totally different primitive cellular lineage — a different tree of life altogether — than bacteria, archaea and eukarya."

So novel are the new genes found in pandoraviruses that scientists have launched into research work to determine exactly what the genes do as the first step to figuring out whether the new viruses warrant the creation of a "fourth domain" of life.
National Geographic reports Claverie and Abergel said that the three-domain system is "probably pretty wrong—we are missing some part of the puzzle here."

However, some experts are saying there isn't any evidence that Pandoravirus represents a "fourth domain of life". According to The New York Times, professor of evolutionary molecular biology at Newcastle University, T. Martin Embley, said: "They provide no evidence for that notion, so it seems a distraction to me." NPR also reports that Eugene Koonin, evolutionary biologist at the National Institutes of Health and a specialist in viruses, said: "These viruses, unusual as they might be, are still related to other smaller viruses. The internal environment of the amoeba cell provides a very good playground for acquiring various kinds of genes from different sources." He predicted: "We are going to see many, many more giant viruses discovered around the world, some of which, probably will be bigger than pandoraviruses."

However, with its novel morphological features and genetic code twice the size of Megavirus, pandoraviruses will eventually add a new range of questions to the abiding question of the origins of life on Earth. Claverie told NPR: "We believe that these new pandoraviruses have emerged from a new ancestral cellular type that no longer exists."

What should come as a relief is that pandoraviruses are not harmful to humans. The New York Times reports that scientists say the giant viruses are very widely distributed, so widely distributed that we have been carrying them around in our bodies all the time without knowing. Recently, a team of French researchers isolated a giant virus from blood donated by a healthy volunteer.

Claverie said: “I don’t believe we have the proof at the moment that these viruses could infect humans," but adds cautiously: "never say never."

http://www.digitaljournal.com/article/354786
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