Contrary to predictions, males of high genetic quality are not very successful when it comes to fertilizing eggs.

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Contrary to predictions, males of high genetic quality are not very successful when it comes to fertilizing eggs. A new study on seed beetles by Swedish and Danish scientists Göran Arnqvist and Trine Bilde shows that when a female mates with several males, the males of low genetic quality are the most successful in fertilizing eggs. The study is published in this week's issue of Science.

In almost all animals, females mate with several different males, despite the fact that a single mating is often sufficient to fertilize her eggs. Multiple mating also carries costs to females, such as the risk of catching sexually transmitted diseases.
One commonly held belief is that this behaviour may allow females to choose the sperm of the male with highest genetic quality to fertilize her eggs. Professor Göran Arnqvist from the Department of Ecology and Evolution, Uppsala University and associate professor Trine Bilde from the Department of Biological Sciences, University of Aarhus, have tested this possibility directly for the first time and shown that it is not true.
Their study on seed beetles shows that, contrary to predictions, males of low genetic quality are more successful in fertilizing eggs. Males who gained the highest share of paternity were actually males with low genetic quality. These males also fathered offspring that did less well.
"The results support the suggestion that genes that are good for males may often be bad for their mates. Therefore, in beetles at least, multiple mating does not award females with genetic benefits," says Göran Arnqvist.
Source: Uppsala University (news : web)

Geography And History Shape Genetic Differences In Humans

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ScienceDaily (June 5, 2009) — New research indicates that natural selection may shape the human genome much more slowly than previously thought. Other factors -- the movements of humans within and among continents, the expansions and contractions of populations, and the vagaries of genetic chance – have heavily influenced the distribution of genetic variations in populations around the world.

The study, conducted by a team from the Howard Hughes Medical Institute, the University of Chicago, the University of California and Stanford University, is published June 5 in the open-access journal PLoS Genetics.
In recent years, geneticists have identified a handful of genes that have helped human populations adapt to new environments within just a few thousand years—a strikingly short timescale in evolutionary terms. However, the team found that for most genes, it can take at least 50,000-100,000 years for natural selection to spread favorable traits through a human population. According to their analysis, gene variants tend to be distributed throughout the world in patterns that reflect ancient population movements and other aspects of population history.
"We don't think that selection has been strong enough to completely fine-tune the adaptation of individual human populations to their local environments," says co-author Jonathan Pritchard. "In addition to selection, demographic history -- how populations have moved around -- has exerted a strong effect on the distribution of variants."
To determine whether the frequency of a particular variant resulted from natural selection, Pritchard and his colleagues compared the distribution of variants in parts of the genome that affect the structure and regulation of proteins to the distribution of variants in parts of the genome that do not affect proteins. Since these neutral parts of the genome are less likely to be affected by natural selection, they reasoned that studying variants in these regions should reflect the demographic history of populations.
The researchers found that many previously identified genetic signals of selection may have been created by historical and demographic factors rather than by selection. When the team compared closely related populations they found few large genetic differences. If the individual populations' environments were exerting strong selective pressure, such differences should have been apparent.
Selection may still be occurring in many regions of the genome, says Pritchard. But if so, it is exerting a moderate effect on many genes that together influence a biological characteristic. "We don't know enough yet about the genetics of most human traits to be able to pick out all of the relevant variation," says Pritchard. "As functional studies go forward, people will start figuring out the phenotypes that are associated with selective signals," says lead author Graham Coop. "That will be very important, because then we can figure out what selection pressures underlie these episodes of natural selection."
But even with further research, much will remain unknown about the processes that have resulted in human traits. In particular, Pritchard and Coop urge great caution in trying to link selection with complex characteristics like intelligence. "We're in the infancy of trying to understand what signals of selection are telling us," says Coop, "so it's a very long jump to attribute cultural features and group characteristics to selection."
Journal reference:
Coop G, Pickrell JK, Novembre J, Kudaravalli S, Li J, et al. The Role of Geography in Human Adaptation. PLoS Genetics, 2009; 5 (6): e1000500 DOI: 10.1371/journal.pgen.1000500
Adapted from materials provided by Public Library of Science, via EurekAlert!, a service of AAAS.

Chemists see first building blocks to life on Earth

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British scientists said on Wednesday that they had figured out key steps in the process by which life on Earth may have emerged from a seething soup of simple chemicals.

Genetic information in living organisms today is held in deoxyribonucleic acid (DNA), the famous "double helix" molecule of sugar, phosphate and a base.
But DNA is too sophisticated to have popped up in an instant, and one avenue of thought says its single-stranded cousin, ribonucleic acid, or RNA, came first.
RNA plays a key role in making proteins and, in viruses, is used to store genetic code.
It is chemically similar to DNA but is simpler and tougher in structure, and thus looks like a good candidate for Earth's first information-coding nucleic acid.
But for all its allure, the "RNA first" theory has run into practical problems.
Its three ingredients -- the base, ribose sugar and phosphate -- must have formed separately and then combined to form the molecule, according to conventional thinking.
Critics, though, say that RNA, while somewhat simpler than DNA, is still a complex molecule and could not have been assembled spontaneously.
These doubters have been comforted by the failure to find any feasible chain of chemical events to explain how the three components all came together.
But a paper published in the British journal Nature by University of Manchester chemists puts forward a different explanation.
The team, led by Professor John Sutherland, venture that an RNA-like synthesis took place through a series of chemical reactions and an important intermediate substance.
Their lab model uses starting materials and environmental conditions that are believed to have been around in early Earth and are also used in the standard "RNA first" scenario.
Their theory starts with a simple sugar called glycolaldehyde, which reacts with cyanmide (a compound of cyanide and ammonia) and phosphate to produce an intermediate compound called 2-aminooxazole.
Gentle warming from the Sun and cooling at night help purify the 2-aminooxazole, turning it into a plentiful precursor which contributes the sugar and base portions of the new ribonucleotide molecule.
The presence of phosphate and ultraviolet light from the Sun complete the synthesis.
In a commentary also published by Nature, US molecular biologist Jack Szostak hailed the research as an elegant explanation as to why the sugar and base would not have to form separately before forming the new molecule.
"It will stand for years as one of the great advances in prebiotic chemistry," the term for the study of the chemical processes that led to life on Earth, he enthused.
Opinions vary as to when the first organisms appeared on Earth.
One estimate, based on fossilised mats of bacteria found in Australia, is that this happened around 3.8 billion years ago, around 700 million years after the planet was formed.
(c) 2009 AFP

Deep in the Red: Using Infrared to Watch What Goes On in a Living Body

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An infrared version of the Nobel Prize-winning green fluorescent protein could make the technique even more powerful.

Fluorescent proteins, which are compounds that can absorb and then emit light, have become a powerful instrument in the cell biologist's toolkit—so powerful, in fact, that the discovery and development of green fluorescent proteins from jellyfish earned the 2008 Nobel Prize in Chemistry. (Here's a Q&A with one of the winners, Columbia University's Martin Chalfie, about his work.) These proteins have limitations, however: They need to be excited with the blue to orange part of the visible spectrum, at wavelengths of 495 to 570 nanometers. These wavelengths of light are too short to penetrate tissue very well, and so green fluorescent proteins are mainly used in test tube studies to watch cell division or to label certain cell types.
But one of the 2008 Nobelists, Roger Y. Tsien of the University of California, San Diego, and his U.C.S.D. colleagues report in today's issue of Science that they have developed a new fluorescent protein that could enable scientists to tag and visualize cellular activity as it happens inside a live animal. The protein, after absorbing light from the far-red part of the spectrum, shines in the near-infrared, at wavelengths of around 700 nanometers.
These longer wavelengths can penetrate mammalian tissue and even pass through bone. "Say you label a tumor with a green fluorescent protein, and if this labeled tumor is buried inside the animal, then you barely can get green fluorescence out," says lead researcher Xiaokun Shu. "But if you label this deeply buried tumor by infrared fluorescent proteins, you will get a stronger signal because infrared penetrates tissue more efficiently."
Tsien's group derived the infrared fluorescent protein from a hardy bacterium called Deinococcus radiodurans, famous for its ability to survive extreme environments. Bacteria do not actually use this class of proteins, called bacteriophytochromes, to emit light. "They use these bacteriophytochromes to control gene expression,” Shu says—the proteins convert absorbed light into energy to signal certain genes to turn on or off.
The initial challenge for researchers was to re-engineer the protein so that absorbed light would be re-emitted instead of being used as a source of power. They accomplished the feat by deleting the part of the protein that converts the absorbed light into chemical energy; as a result, this truncated and mutant form gave up its absorbed energy as an infrared glow. The scientists incorporated the engineered bacterial protein into mammalian cells—specifically, into the liver of a live mouse, which lit up with infrared light.
The finding paves the way for in vivo visualization of a wide range of biochemical processes and internal organs in animals. (Its use in humans is unlikely, as it would require gene therapy and the ethically dubious transplantation of bacterial genes into humans.)
“This is so important," comments David James, a cell biologist from Australia's Garvan Institute in Sydney, "because a lot of knowledge at the moment is confined to individual cells grown on a glass coverslip," leaving open the question of whether that knowledge "is transferable to an animal." The infrared version could also solve the problem of naturally occuring fluorescence from other biological molecules, which tend to glow at wavelengths similar to conventional fluorescent protein markers and thereby create a lot of “background noise," James says.

But even greater potential lies in harnessing the bacteriophytochrome's original function, namely, powering gene expression. It should be feasible, Tsien thinks, to put back in the signal-controlling properties of the phytochrome. Then it could be possible with animals to “switch on genes and control biochemistry" with light, he says.
For example, you want to explore the effects on mouse behavior of switching on a particular gene that controls some aspect of brain function, but, thankfully for the mouse, you do not want to open up its skull or stick a needle in its brain. "If the infrared fluorescent protein can be made to turn back into an infrared phytochrome, you could have the switch all ready and just waiting for enough infrared light," Tsien speculates. Because infrared light can penetrate the skull, it can reach the phytochrome and remotely switch the gene on, resulting in observable changes in the mouse's behavior.
It's the next evolutionary step for fluorescent proteins, remarks Tsien, who believes that phytochromes represent a class of proteins with enormous potential. If he's correct, then in the coming years, expect more scientists to see the (infrared) light.

By Bianca Nogrady

Sizing Cells Up: Researchers Pinpoint When A Cell Is Ready To Reproduce

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http://www.blogger.com/post-create.g?blogID=4305283407805626298

Science Daily — For more than 100 years, scientists have tried to figure out the cell size problem: How does a cell know when it is big enough to divide?

In research conducted in budding yeast (Saccharomyces cerevisiae), scientists at Rockefeller University have now identified the cellular event that marks the moment when a cell knows it is big enough to commit to cell division and spawn genetic replicas of itself. The findings provide a precise and quantitative framework for studying the possible mechanisms that allow cells to monitor and sense their size.
During the first phase of the cell cycle, known as G1, budding yeast grows and begins to form a bud; in the final stage, the cell splits into two — one bigger than the other. Although researchers have identified several key proteins that regulate and play a role in coordinating cell growth and division during G1, they have not been able to get to the core mechanism that senses whether a cell possesses enough resources to divide. Scientists needed a way to organize and confidently sort out molecular candidates involved in cell size control from those that played other roles.
Graduate student Stefano Di Talia, a biophysicist, and postdoc Jan Skotheim, an applied mathematician, provided just that. Working with Eric Siggia, head of the Laboratory of Theoretical Condensed Matter Physics, and Fred Cross, head of the Laboratory of Yeast Molecular Genetics, Di Talia and Skotheim showed that a unique cellular event, the exiting of the protein Whi5 from the nucleus, separates G1 into two independent steps: one controlled by a sizer (T1) and one controlled by a timer (T2). T1 begins when the mother and daughter cells have completely separated from each other; T2 starts in G1 once Whi5 has exited the nucleus and lasts until the new daughter cell forms its own bud.
“You need some way to know how big you are,” says first author Di Talia, whose work appears in the August 23 issue of Nature. “This precise quantitative framework allows us to narrow down the possibility of events that are involved in size control.”
By measuring the sizes of budding yeast and how long they spend in G1 and in T1, Di Talia saw that daughter cells, which are much smaller than their mother cells, need to spend more time in T1 growing. Once daughter cells reach the required size for division, they spend as much time as their mothers in T2, subsequently replicating their DNA and producing daughter cells of their own. Di Talia and his colleagues used genetics to show that a different medley of proteins coordinate cell growth and division during T1 and T2, a crucial finding highlighting that these two parts of G1 are independent from each other and are regulated by different mechanisms.
“If we continue to identify the molecular events that change how T1 is regulated,” says Di Talia, “we can really hope to get to the core of what the size-sensing machinery is.”
Nature 448(7156): 947-951 (August 23, 2007)
Note: This story has been adapted from material provided by Rockefeller University.

Fausto Intilla

www.oloscience.com

Mystery Behind How Nuclear Membrane Forms During Mitosis Solved

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http://www.sciencedaily.com/releases/2007/09/070915100302.htm

Science Daily — Just how a dividing cell rebuilds the nuclear envelope, the protective, functional wrapping that encases both the original and newly copied genetic material, has been a source of controversy for the last 20 years.

The answer matters because the architecture established during formation of the envelope is regarded as key to future regulation of gene expression.
Now scientists at the Salk Institute of Biological Studies, reporting in the September 9 advanced online edition of Nature Cell Biology, lay the debate to rest. Studying frog eggs, they discovered that the endoplasmic reticulum (ER), a key cellular organelle shaped like a network of tubes, flattens part of itself during mitosis to form a double-sided sheet, which then bends around what will become the nucleus, the control hub of the cell.
“The process is simple and elegant,” says Martin W. Hetzer, Ph.D., an assistant professor in the Molecular and Cell Biology Laboratory, who explains, “the membrane tubules are flattened as they associate with chromatin. Our model does not involve vesicle fusion.”
The most dramatic event during nuclear assembly following replication and separation of chromosomes is the reformation of the nuclear envelope, a highly structured barrier that separates the nuclear interior from the rest of the cell, say Hetzer and Daniel J. Anderson, a graduate student in Hetzer’s lab and co-author of the study. The envelope is the gateway into the nucleus and, thus, restricts access to the genome; it is composed of a concentric double membrane that is penetrated by nuclear pores, which serve as transport channels between the nucleus and the cytoplasm.
Just as chromosomes duplicate, the cell’s organelles, including the ER, also reproduce themselves. “The ER is always there and remains an intact network of tubes,” says Hetzer. In a mature cell the ER works closely with the genome, synthesizing and transporting the proteins produced under the direction of genes housed inside the nucleus.
Some scientists have believed that the ER in the sister cells help form the nuclear envelope, although proof of the process has been lacking. Others have argued that the new membrane is resurrected from bits of the “old” nuclear membrane that disintegrates when nuclear chromosomes duplicate and pull apart during mitosis.
“The problem with this theory, however, is that these fragments would then have to be fused together in the newly produced cells, and that would require massive membrane fusion and a dedicated protein machinery,” Hetzer says. “But no one has ever found it. Our data suggests that the search for this fusion machinery is now obsolete,” he says.
Hetzer and Anderson used a popular scientific model of mitosis, the eggs of Xenopus, an African frog, to determine how the nuclear envelope is restored. They found that the tubules of the ER are connected to each other in a three-way junction that allows them to constantly move and change position relative to each other.
During the early phases of mitosis, the end of the tubes bind directly to DNA found at the surface of the chromatin, the tightly bundled coil of genetic material and proteins that form chromosomes after DNA replication. Then, as mitosis proceeds, extra DNA binding proteins that reside in the ER are employed to progressively immobilize some of the tubules, flattening them out to create the nuclear membrane
“The tubules are squeezed into flat sheets that merge with each other, forming large membrane sheets that cover the entire surface of the chromatin,” Hetzer says. Why this matters, according to Hetzer, is because it is becoming increasingly clear that the nuclear envelope plays an important role in cell function.
“Anchorage of chromatin at the nuclear periphery and its three-dimensional organization within the nuclear interior helps regulate gene expression, and we know that mutations in nuclear envelope proteins cause a variety of different human diseases,” he says. “So knowing how the nuclear membrane is assembled will help us understand nuclear architecture and, in the long run, gene expression.”
The study was funded by NIH and a Pew Scholar Award.
Animation available: http://www.salk.edu/video/Sec61-U2OS-1/Sec61-U2OS-1.html
Note: This story has been adapted from a news release issued by Salk Institute for Biological Studies.

Fausto Intilla

www.oloscience.com

Synthetic Biology? Memory In Yeast Cells Synthesized

Source:

http://www.sciencedaily.com/releases/2007/09/070915081448.htm

Science Daily — Harvard Medical School researchers have successfully synthesized a DNA-based memory loop in yeast cells, findings that mark a significant step forward in the emerging field of synthetic biology.
After constructing genes from random bits of DNA, researchers in the lab of Professor Pamela Silver, a faculty member in Harvard Medical School's Department of Systems Biology, not only reconstructed the dynamics of memory, but also created a mathematical model that predicted how such a memory "device" might work.
"Synthetic biology is an incredibly exciting field, with more possibilities than many of us can imagine," says Silver, lead author of the paper to be published in the September 15 issue of the journal Genes and Development. "While this proof-of-concept experiment is simply one step forward, we've established a foundational technology that just might set the standard of what we should expect in subsequent work."
Like many emerging fields, there's still a bit of uncertainty over what, exactly, synthetic biology is. Ask any three scientists for a definition, and you'll probably get four answers.
Some see it as a means to boost the production of biotech products, such as proteins for pharmaceutical uses or other kinds of molecules for, say, environmental clean-up. Others see it as a means to creating computer platforms that may bypass many of the onerous stages of clinical trials. In such a scenario, a scientist would type the chemical structure of a drug candidate into a computer, and a program containing models of cellular metabolism could generate information on how people would react to that compound.
Either way, at it's core, synthetic biology boils down to gleaning insights into how biological systems work by reconstructing them. If you can build it, it forces you to understand it.
A team in Silver's Harvard Medical School lab led by Caroline Ajo-Franklin, now at Lawrence Berkeley National Laboratory, and postdoctoral scientist David Drubin decided to demonstrate that not only could they construct circuits out of genetic material, but they could also develop mathematical models whose predictive abilities match those of any electrical engineering system.
"That's the litmus test," says Drubin, "namely, building a biological device that does precisely what you predicted it would do."
The components of this memory loop were simple: two genes that coded for proteins called transcription factors.
Transcription factors regulate gene activity. Like a hand on a faucet, the transcription factor will grab onto a specific gene and control how much, or how little, of a particular protein the gene should make.
The researchers placed two of these newly synthesized, transcription factor-coding genes into a yeast cell, and then exposed the cell to galactose (a kind of sugar). The first gene, which was designed to switch on when exposed to galactose, created a transcription factor that grabbed on to, and thus activated, the second gene.
It was at this point that the feedback loop began.
The second gene also created a transcription factor. But this transcription factor, like a boomerang, swung back around and bound to that same gene from which it had originated, reactivating it. This caused the gene to once again create that very same transcription factor, which once again looped back and reactivated the gene.
In other words, the second gene continually switched itself on via the very transcription factor it created when it was switched on.
The researchers then eliminated the galactose, causing the first synthetic gene, the one that had initiated this whole process, to shut off. Even with this gene gone, the feedback loop continued.
"Essentially what happened is that the cell remembered that it had been exposed to galactose, and continued to pass this memory on to its descendents," says Ajo-Franklin. "So after many cell divisions, the feedback loop remained intact without galactose or any other sort of molecular trigger."
Most important, the entire construction of the device was guided by the mathematical model that the researchers developed.
"Think of how engineers build bridges," says Silver. "They design quantitative models to help them understand what sorts of pressure and weight the bridge can withstand, and then use these equations to improve the actual physical model. We really did the same thing. In fact, our mathematical model not only predicted exactly how our memory loop would work, but it informed how we synthesized the genes."
For synthetic biology, this kind of specificity is crucial. "If we ever want to create biological black boxes, that is, gene-based circuits like this one that you can plug into a cell and have it perform a specified task, we need levels of mathematical precision as exact as the kind that go into creating computer chips," she adds.
The researchers are now working to scale-up the memory device into a larger, more complex circuit, one that can, for example, respond to DNA damage in cells.
"One day we'd like to have a comprehensive library of these so-called black boxes," says Drubin. "In the same way you take a component off the shelf and plug it into a circuit and get a predicted reaction, that's what we'd one day like to do in cells."
For an animation of how to construct a synthetic memory loop see http://hms.harvard.edu/public/video/silver_illustration.mov
Full Citation: Caroline M. Ajo-Franklin(1), David A. Drubin(1), Julian A. Eskin(1), Elaine P.S. Gee(2), Dirk Landgraf(1), Ira Phillips(1), and Pamela A. Silver(1), "Rational design of memory in eukaryotic cells", Genes and Development, Volume 21, Issue 18: September 15, 2007
1-Department of Systems Biology, Harvard Medical School, 200 Longwood Ave., Boston MA 2-Harvard University Program in Biophysics, Massachusetts Institute of Technology, Cambridge, MA
Note: This story has been adapted from a news release issued by Harvard Medical School.

Fausto Intilla
www.oloscience.com

Microfluidic Chambers Advance The Science Of Growing Neurons

Source:

http://www.sciencedaily.com/releases/2007/08/070830160803.htm

Science Daily — Researchers at the University of Illinois have developed a method for culturing mammalian neurons in chambers not much larger than the neurons themselves. The new approach extends the lifespan of the neurons at very low densities, an essential step toward developing a method for studying the growth and behavior of individual brain cells.

The technique is described this month in the journal of the Royal Society of Chemistry – Lab on a Chip.
“This finding will be very positively greeted by the neuroscience community,” said Martha Gillette, who is an author on the study and the head of the cell and developmental biology department at Illinois. “This is pushing the limits of what you can do with neurons in culture.”
Growing viable mammalian neurons at low density in an artificial environment is no easy task. Using postnatal neurons only adds to the challenge, Gillette said, because these cells are extremely sensitive to environmental conditions.
All neurons rely on a steady supply of proteins and other “trophic factors” present in the extracellular fluid. These factors are secreted by the neurons themselves or by support cells, such as the glia. This is why neurons tend to do best when grown at high density and in the presence of other brain cells. But a dense or complex mixture of cells complicates the task of characterizing the behavior of individual neurons.
One technique for keeping neural cultures alive is to grow the cells in a medium that contains serum, or blood plasma. This increases the viability of cells grown at low density, but it also “contaminates” the culture, making it difficult to determine which substances were produced by the cells and which came from the serum.
Those hoping to understand the cellular origins of trophic factors in the brain would benefit from a technique that allows them to measure the chemical outputs of individual cells. The research team made progress toward this goal by addressing a few key obstacles.
First, the researchers scaled down the size of the fluid-filled chambers used to hold the cells. Chemistry graduate student Matthew Stewart made the small chambers out of a molded gel of polydimethylsiloxane (PDMS). The reduced chamber size also reduced – by several orders of magnitude – the amount of fluid around the cells, said Biotechnology Center director Jonathan Sweedler, an author on the study. This “miniaturization of experimental architectures” will make it easier to identify and measure the substances released by the cells, because these “releasates” are less dilute.
“If you bring the walls in and you make an environment that’s cell-sized, the channels now are such that you’re constraining the releasates to physiological concentrations, even at the level of a single cell,” Sweedler said.
Second, the researchers increased the purity of the material used to form the chambers. Cell and developmental biology graduate student Larry Millet exposed the PDMS to a series of chemical baths to extract impurities that were killing the cells.
Millet also developed a method for gradually perfusing the neurons with serum-free media, a technique that resupplies depleted nutrients and removes cellular waste products. The perfusion technique also allows the researchers to collect and analyze other cellular secretions – a key to identifying the biochemical contributions of individual cells.
“We know there are factors that are communicated in the media between the cells,” Millet said. “The question is what are they, and how can we get at those?”
This combination of techniques enabled the research team to grow postnatal primary hippocampal neurons from rats for up to 11 days at extremely low densities. Prior to this work, cultured neurons in closed-channel devices made of untreated, native PDMS remained viable for two days at best.
The cultured neurons also developed more axons and dendrites, the neural tendrils that communicate with other cells, than those grown at low densities with conventional techniques, Gillette said.
“Not only have we increased the cells’ viability, we’ve also increased their ability to differentiate into what looks much more like a mature neuron,” she said.
Sweedler noted that the team’s successes are the result of a unique collaboration among scientists with very different backgrounds.
“(Materials science and engineering professor) Ralph Nuzzo is one of the pioneers in self-assembled monolayers and surface chemistry,” Sweedler said. “Martha Gillette’s expertise is in understanding how these neurons grow, and in imaging them. My lab does measurement science on a very small scale. It’s almost impossible for any one lab to do all that.”
Nuzzo and Sweedler are William H. and Janet Lycan professors of chemistry. Gillette is Alumni Professor of Cell and Developmental Biology. All are appointed in the Institute for Genomic Biology. Sweedler and Gillette are affiliates of the Beckman Institute and the Neuroscience Program. Sweedler is a professor in the Bioengineering Program and Gillette in the College of Medicine.
Note: This story has been adapted from a news release issued by University of Illinois at Urbana-Champaign.

Fausto Intilla

www.oloscience.com