March 17, 2010, 8:17 PM CT

Spider silk reveals a paradox

Since its development in China thousands of years ago, silk from silkworms, spiders and other insects has been used for high-end, luxury fabrics as well as for parachutes and medical sutures. Now, National Science Foundation-supported scientists are untangling some of its most closely guarded secrets, and explaining why silk is so super strong.

Scientists at the Massachusetts Institute of Technology's Center for Materials Science and Engineering say the key to silk's pound-for-pound toughness, which exceeds that of steel, is its beta-sheet crystals, the nano-sized cross-linking domains that hold the material together.

Markus Buehler, the Esther and Harold E. Edgerton Associate Professor in MIT's department of civil and environmental engineering, and his team recently used computer models to simulate exactly how the components of beta sheet crystals move and interact with each other. They observed that an unusual arrangement of hydrogen bonds--the "glue" that stabilizes the beta-sheet crystals--play an important role in defining the strength of silk.

They observed that hydrogen bonds, which are among the weakest types of chemical bonds, gain strength when confined to spaces on the order of a few nanometers in size. Once in close proximity, the hydrogen bonds work together and become extremely strong. Moreover, if a hydrogen bond breaks, there are still a number of hydrogen bonds left that can contribute to the material's overall strength, due to their ability to "self-heal" the beta-sheet crystals......... Posted by: Kelly      Read more         Source

March 15, 2010, 8:06 PM CT

3-D cell culture

The film "Avatar" isn't the only 3-D blockbuster making a splash this winter. A team of researchers from Houston's Texas Medical Center this week unveiled a new technique for growing 3-D cell cultures, a technological leap from the flat petri dish that could save millions of dollars in drug-testing costs. The research is reported in Nature Nanotechnology

The 3-D technique is easy enough for most labs to set up immediately. It uses magnetic forces to levitate cells while they divide and grow. Compared with cell cultures grown on flat surfaces, the 3-D cell cultures tend to form tissues that more closely resemble those inside the body.

"There's a big push right now to find ways to grow cells in 3-D because the body is 3-D, and cultures that more closely resemble native tissue are expected to provide better results for preclinical drug tests," said co-author of study Tom Killian, associate professor of physics at Rice. "If you could improve the accuracy of early drug screenings by just 10 percent, it's estimated you could save as much as $100 million per drug".

For cancer research, the "invisible scaffold" created by the magnetic field goes beyond its potential for producing cell cultures that are more reminiscent of real tumors, which itself would be an important advance, said co-author Wadih Arap, professor in the David H. Koch Center at The University of Texas M.D. Anderson Cancer Center......... Posted by: Janet      Read more         Source

March 15, 2010, 7:57 PM CT

How sea lilies got their get-up-and-go

Nature abounds with examples of evolutionary arms races. Certain marine snails, for example, evolved thick shells and spines to avoid be eaten, but crabs and fish foiled the snails by developing shell-crushing claws and jaws.

Common as such interactions appears to be, it's often difficult to trace their origins back in evolutionary time.

Now, a study by University of Michigan paleontologist Tomasz Baumiller and his colleagues finds that sea urchins have been preying on marine animals known as crinoids for more than 200 million years and suggests that such interactions drove one type of crinoid---the sea lily---to develop the ability to escape by creeping along the ocean floor. The work, which builds on prior research on present-day sea lilies and urchins, is scheduled to be published online this week in the Proceedings of the National Academy of Sciences

With their long stalks and feathery arms, sea lilies look a lot like their garden-variety namesakes. Perhaps because of that resemblance, researchers long had thought that sea lilies stayed rooted instead of moving around like their stalkless relatives, the feather stars. But in the 1980s, Baumiller and collaborator Charles Messing of Nova Southeastern University's Oceanographic Center in Dania Beach, Fla., observed sea lilies shedding the ends of their stalks to release themselves from their anchor points and using their feathery arms to crawl away, dragging their stalks behind them......... Posted by: Janet      Read more         Source

March 14, 2010, 8:17 PM CT

Opium poppy's biggest secret

Scientists at the University of Calgary have discovered the unique genes that allow the opium poppy to make codeine and morphine, thus opening doors to alternate methods of producing these effective painkillers either by manufacturing them in a lab or controlling the production of these compounds in the plant.

"The enzymes encoded by these two genes have eluded plant biochemists for a half-century," says Peter Facchini, professor in the Department of Biological Sciences, who has dedicated his career to studying the unique properties of the opium poppy. "In finding not only the enzymes but also the genes, we've made a major step forward. It's equivalent in finding a gene involved in cancer or other inherited disorders".

The researchers' findings will be published in a paper entitled Dioxygenases catalyze the O-demethylation steps of morphine biosynthesis in opium poppy, appearing in the on-line edition of Nature Chemical Biology (http://www.nature.com/nchembio/index.html) on Sun., Mar. 14 at 2 pm ET / 6 pm London time.

Codeine is by far the most widely used opiate in the world and one of the most usually used painkillers. Codeine can be extracted directly from the plant, most codeine is synthesized from the much more abundant morphine found in opium poppy. Codeine is converted by an enzyme in the liver to morphine, which is the active analgesic and a naturally occurring compound in humans. Canadians spend more than $100 million every year on codeine-containing pharmaceutical products and are among the world's top consumers of the drug per capita. Despite this, Canada imports all of its opiates from other countries......... Posted by: Erica      Read more         Source

March 14, 2010, 8:13 PM CT

Sequencing Hydra genome

UC Irvine scientists have played a leading role in the genome sequencing of Hydra, a freshwater polyp that has been a staple of biological research for 300 years.

In the March 14 online version of Nature, UCI biologists Robert Steele and Hans Bode, along with nine other UCI researchers and an international team of researchers, describe the genome sequence of an organism that continues to advance research on regeneration, stem cells and patterning.

The team discovered Hydra to have about the same number of genes as humans, sharing a number of of the same ones. Surprisingly, they also found genes linked with Huntington's disease and with the beta-amyloid plaque formation seen in Alzheimer's disease two areas in which UCI has traditionally strong research programs suggesting the possible use of Hydra as a research model for these two diseases.

"Having the Hydra genome sequenced also enhances our ability to use it to learn more about the basic biology of stem cells, which are showing great promise for new therapys for a host of injuries and diseases," said Steele, associate professor and interim chair in biological chemistry.

Started in 2004, the Hydra project is the first genome sequencing effort in which UCI researchers have played a major role. The sequencing was carried out at the J. Craig Venter Institute and was funded by the National Human Genome Research Institute......... Posted by: Janet      Read more         Source

March 12, 2010, 7:41 AM CT

Why female moths are big and beautiful?

In most animal species, males and females show obvious differences in body size. But how can this be, given that both sexes share the same genes governing their growth? University of Arizona entomologists studied this conundrum in moths and found clues that had been overlooked by prior efforts to explain this mystery of nature.

Take a look around in the animal world and you will find that, in most organisms, individuals of one sex are larger than the other of the species.

Even though evolutionary biologists have long recognized this discrepancy, called sexual dimorphism, they have struggled for decades to solve a major paradox: How can males and females of one species be of different sizes, given that they share the same genetic blueprints dictating their development and growth?

Scientists from the University of Arizona have discovered that the key to unraveling this mystery lies in the early developmental stages during which the sexes begin to grow apart and that females can respond to selection on size almost twice as fast as can males.

Their findings are published online before print in Proceedings of the Royal Society of London, Series B

"In mammals, the males tend to be larger because there is an advantage in being bigger and stronger when it comes to fighting over who gets the female," explained Craig Stillwell, main author of the study and a UA Center for Insect Science postdoctoral fellow in the lab of Goggy Davidowitz, an assistant professor of entomology at the UA......... Posted by: Kelly      Read more         Source

March 12, 2010, 7:31 AM CT

600 million-year-old origins of vision

By studying the hydra, a member of an ancient group of sea creatures that is still flourishing, researchers at UC Santa Barbara have made a discovery in understanding the origins of human vision. The finding is published in this week's issue of the Proceedings of the Royal Society B, a British journal of biology.

Hydra are simple animals that, along with jellyfish, belong to the phylum cnidaria. Cnidarians first emerged 600 million years ago.

"We determined which genetic 'gateway,' or ion channel, in the hydra is involved in light sensitivity," said senior author Todd H. Oakley, assistant professor in UCSB's Department of Ecology, Evolution and Marine Biology. "This is the same gateway that is used in human vision".

Oakley explained that there are a number of genes involved in vision, and that there is an ion channel gene responsible for starting the neural impulse of vision. This gene controls the entrance and exit of ions; i.e., it acts as a gateway.

The gene, called opsin, is present in vision among vertebrate animals, and is responsible for a different way of seeing than that of animals like flies. The vision of insects emerged later than the visual machinery found in hydra and vertebrate animals.

"This work picks up on earlier studies of the hydra in my lab, and continues to challenge the misunderstanding that evolution represents a ladder-like march of progress, with humans at the pinnacle," said Oakley. "Instead, it illustrates how all organisms humans included are a complex mix of ancient and new characteristics"......... Posted by: Janet      Read more         Source

March 12, 2010, 7:27 AM CT

Myths about Amazon rain forests

A new NASA-funded study has concluded that Amazon rain forests were remarkably unaffected in the face of once-in-a-century drought in 2005, neither dying nor thriving, contrary to a previously published report and claims by the Intergovernmental Panel on Climate Change.

"We found no big differences in the greenness level of these forests between drought and non-drought years, which suggests that these forests appears to be more tolerant of droughts than we previously thought," said Arindam Samanta, the study's main author from Boston University.

The comprehensive study reported in the current issue of the scientific journal Geophysical Research Letters used the latest version of the NASA MODIS satellite data to measure the greenness of these vast pristine forests over the past decade.

A study reported in the journal Science in 2007 claimed that these forests actually thrive from drought because of more sunshine under cloud-less skies typical of drought conditions. The newly released study observed that those results were flawed and not reproducible.

"This newly released study brings some clarity to our muddled understanding of how these forests, with their rich source of biodiversity, would fare in the future in the face of twin pressures from logging and changing climate," said Boston University Prof. Ranga Myneni, senior author of the newly released study......... Posted by: Erica      Read more         Source

March 11, 2010, 11:06 PM CT

Yellow fever strikes monkey populations

A group of Argentine scientists, including health experts from the Wildlife Conservation Society, have announced that yellow fever is the culprit in a 2007-2008 die-off of howler monkeys in northeastern Argentina, a finding that underscores the importance of paying attention to the health of wildlife and how the health of people and wild nature are so closely linked.

The paperappearing in a recent edition of the American Journal of Primatologyfocuses on yellow fever outbreaks that were documented in several howler monkey populations of Misiones Province, Argentina. The epidemics, which caused the death of dozens of rare howler monkeys, signaled the need for a human vaccination program in the region to save lives.

The authors of the study include: Ingrid Holzmann and Mario S. Di Bitetti of the Argentine Council for Science and Technology (CONICET); Ilaria Agostini of the Universidad de Roma and CNR; Juan Ignacio Areta of Grupo FALCO; and Hebe Ferreyra and Pablo Beldomenico of the Wildlife Conservation Society.

"The outbreak has tragic conservation implications for the endangered brown howler monkey, one of the two species affected, which is highly threatened primarily by habitat destruction, hunting, and now disease," said Dr. Pablo Beldomenico. "The study also points out the importance of wildlife as a critically important indicator of health and disease processes which can help protect people too."........ Posted by: Kelly      Read more         Source

March 10, 2010, 8:20 AM CT

Hidden habits and movements of insect pests

For a high-resolution image of the Asota caricae moth referenced in the article, visit http://bit.ly/aB4PEb. The moth has a two-inch wingspan and a 2,500 mile distribution. Image is courtesy of Lauren Helgen, Smithsonian Institution. For a copy of the research paper, contact Jeff Falk at jfalk@umn.edu.

Contacts: Peggy Rinard, College of Biological Sciences, rinar001@umn.edu, (612) 624-0774.

Jeff Falk, University News Service, jfalk@umn.edu, (612) 626-1720.

MINNEAPOLIS / ST. PAUL (03/09/2010) -University of Minnesota researcher George Weiblen and his colleagues have found a faster way to study the spread and diet of insect pests.

Using a technique called DNA barcoding, which involves the identification of species from a short DNA sequence, Weiblen and an international team of scientists studied populations of numerous moth and butterfly species across Papua New Guinea. DNA barcodes showed that migratory patterns and caterpillar diets are very dynamic. In one case, a tiny moth that is distributed from Taiwan to Australia, has recently crossed thousands of miles of Pacific Ocean.

The research, "Population genetics of ecological communities with DNA barcodes: An example from New Guinea Lepidoptera," was reported in the Early Online edition of Proceedings of the National Academy of Sciences on March 1......... Posted by: Kelly      Read more         Source

March 9, 2010, 8:30 AM CT

Musk Ox Population Decline Due to Climate

team of researchers has discovered that the drastic decline in Arctic musk ox populations that began roughly 12,000 years ago was due to a warming climate rather than to human hunting. "This is the first study to use ancient musk ox DNA collected from across the animal's former geographic range to test for human impacts on musk ox populations," said Beth Shapiro, the Shaffer Career Development assistant professor of biology at Penn State University and one of the team's leaders. "We observed that, eventhough human and musk ox populations overlapped in a number of regions across the globe, humans probably were not responsible for the decline and eventual extinction of musk oxen across much of their former range." The team's findings would be reported in the 8 March 2010 issue of the journal Proceedings of the National Academy of Sciences.

Musk oxen once were plentiful across the entire Northern Hemisphere, but they now exist almost solely in Greenland and number only about 80,000 to 125,000. As per the researchers, musk oxen are not the only animals to suffer during the late Pleistocene Epoch. "The late Pleistocene was marked by rapid environmental change as well as the beginning of the spread of humans across the Northern Hemisphere," said Shapiro. "During that time several animals became extinct, including mammoths and woolly rhinoceroses, while others, including horses, caribou, and bison, survived into the present. The reasons for these drastically different survival patterns have been debated widely, with some researchers claiming that the extinctions were due largely to human hunting. Musk oxen provide a unique opportunity to study this question because they suffered from a decline in their population that coincided with the Pleistocene extinctions, yet they still exist today, which allows us to compare the genetic diversity of today's individuals with those individuals that lived up to 60,000 years ago"......... Posted by: Kelly      Read more         Source

March 8, 2010, 9:09 AM CT

Snake venom charms science world

The King Cobra continues to weave its charm with scientists identifying a protein in its venom with the potential for new drug discovery and to advance understanding of disease mechanisms.

The novel protein named haditoxin has been described in the prestigious Journal of Biological Chemistry (March 12, 2010).

The editorial board of the journal has selected this work as the "Paper of the Week" recognising it as being in the top one per cent of their published articles in terms of significance and overall importance.

Haditoxin was discovered in Professor Manjunatha Kini's laboratory at the National University of Singapore. Co-author of the paper Dr S. Niru Nirthanan, now at Griffith University on the Gold Coast, has characterised the pharmacological actions of haditoxin.

Dr Nirthanan said that haditoxin was structurally unique and therefore expected to have unique pharmacological properties.

"This toxin is like a conjoined twin. It is a relatively large complex made up of two identical protein molecules known as three-finger toxins associated withgether."

"We know that the family of three-finger toxins display diverse biological actions on the human nervous system, cardiovascular system and blood clotting. Some have directly led to the development of compounds with potent analgesic and blood pressure reducing properties so it is likely that haditoxin in its 'conjoined twin' state or as individual components will offer us more novel insights," he said......... Posted by: Kelly      Read more         Source

February 25, 2010, 2:52 AM CT

Tree-dwelling mammals climb to the heights of longevity

The squirrels littering your lawn with acorns as they bound overhead will live to plague your yard longer than the ones that aerate it with their burrows, as per a University of Illinois study.

Researchers know from prior studies that flying birds and bats live longer than earthbound animals of the same size. Milena Shattuck and Scott Williams, doctoral candidates in anthropology, decided to take a closer look at the relationship between habitat and lifespan in mammals, comparing terrestrial and treetop life. They published their findings in the Proceedings of the National Academy of Sciences.

The two hypothesized that, like flight, treetop or arboreal dwelling reduces a species' extrinsic mortality - death from predation, disease and environmental hazards; that is, causes other than age.

"One of the predictions of the evolutionary theory of aging is that if you can reduce sources of extrinsic mortality, you'll end up exposing some of the late-acting mutations to natural selection, and therefore evolve longer lifespans," Williams said.

Williams and Shattuck observed that for arboreality, the theory holds. Mammals who spend the majority of their time up a tree enjoy longevity over those who scurry along the ground. The pattern holds consistent both on the large scale among all mammals, and also in specific classes the pair studied, such as tree squirrels versus ground squirrels......... Posted by: Kelly      Read more         Source

February 18, 2010, 10:00 PM CT

Forage Plant Fights Parasites

common pasture plant could help foraging ruminants ward off damaging gastrointestinal nematodes that can cause illness and death, Agricultural Research Service (ARS) researchers report.

Animal scientist Joan Burke at the ARS Dale Bumpers Small Farms Research Center in Booneville, Ark., along with colleagues at several universities, has patented formulations of Sericea lespedeza, usually referred to as Chinese bush clover. The plant was introduced in the United States in the 1930s to minimize soil erosion.

Adding the patented dry hay and pelleted forms of this plant to animal feed thwarts the reproductive cycles of gastrointestinal nematodes that are in the digestive tracts of goats and sheep. It is especially effective in controlling the barber pole worm (Haemonchus contortus), a nematode that attaches to the animals' abomasal (true stomach) wall and feeds on their blood. Female worms can produce more than 5,000 eggs per day that are shed in the animal's manure.

After hatching outside the animal, H. contortus larvae molt several times, resulting in a more developed and infectious larval form on grass leaves that animals consume during grazing. Once the infectious larvae are inside the animal, they suck the animal's blood, potentially leading to anemia, weakness and even death......... Posted by: Erica      Read more         Source

February 18, 2010, 9:19 PM CT

From Carnivorous Plants to the Medicine Cabinet?

In the tropics, carnivorous plants trap unsuspecting prey in a cavity filled with liquid known as a "pitcher".

The moment insects like flies, ants and beetles fall into a pitcher, the plant's enzymes are activated and begin dissolving their new meal, obtaining nutrients such as carbon and nitrogen which are difficult to extract from certain soils. Carnivorous plants also possess a highly developed set of compounds and secondary metabolites to aid in their survival.

These compounds could serve as a new class of anti-fungal drugs for use in human medicine, says Prof. Aviah Zilberstein of Tel Aviv University's Department of Plant Sciences. In a study conducted together with Dr. Haviva Eilenberg from her lab, Prof. Esther Segal from the Sackler Faculty of Medicine and Prof. Shmuel Carmeli from the School of Chemistry, the unusual components from the plants' pitchers were found effective as anti-fungal drugs against human fungal infections widespread in hospitals. The primary results are encouraging.

"To avoid sharing precious food resources with other micro-organisms such as fungi, the carnivorous plant has developed a host of agents that act as natural anti-fungal agents," says Prof. Zilberstein. "In the natural habitat of the tropics, competition for food is fierce, and the hot, moist environment is perfect for fungi, which would also love to eat the plant's insect meal"......... Posted by: Erica      Read more         Source

February 11, 2010, 8:17 AM CT

Big Cats in Serious Trouble Around the World

As a number of Asian countries prepare to celebrate Year of the Tiger beginning February 14, World Wildlife Fund (WWF) reports that tigers are in crisis around the world, including here in the United States, where more tigers are kept in captivity than are alive in the wild throughout Asia. As few as 3,200 tigers exist in the wild in Asia where they are threatened by poaching, habitat loss, illegal trafficking and the conversion of forests for infrastructure and plantations.

WWF is releasing a new interactive map of the world's top 10 tiger trouble spots and the main threats against tigers. WWF is also launching a campaign: Tx2: Double or Nothing to support tiger range states in their goal of doubling wild tiger numbers by the next Year of the Tiger in 2022.

The issues highlighted in the trouble spots map (www.worldwildlife.org/troublespots) include:

• Pulp, paper, palm oil and rubber companies are devastating the forests of Indonesia and Malaysia, home to two endangered tiger sub-species;
• Hundreds of new or proposed dams and roads in the Mekong region will fragment tiger habitat;
• Illegal trafficking in tiger bones, skins and meat feeds a continued demand in East and Southeast Asia;
• More tigers are kept in captivity in the U.S. than are left in the wild -- and there are few regulations to keep these tigers from ending up on the black market. The largest numbers of captive tigers are in Texas (an estimated 3,000+), but they are also kept in other states;
........


Posted by: Kelly      Read more         Source

February 11, 2010, 8:13 AM CT

Genome sequence for advancement

A global initiative that includes key researchers from Oregon State University has successfully sequenced the genome of the wild grass Brachypodium distachyon, which will serve as a model to speed research on improved varieties of wheat, oats and barley, as well as switchgrass, a crop of major interest for biofuel production.

The advance was announced recently in the journal Nature.

The primary international repository for the Brachypodium genome sequence data, called "BrachyBase," is situated at OSU, and helps researchers around the world make important advances for human nutrition and new energy sources.

Brachypodium is actually a wild annual grass plant, native to the Mediterranean and Middle East, with little agricultural importance and is of no major economic value itself. But it allows scientists to obtain genetic information for grasses much more easily than some of its related, but larger and more complex counterparts with much larger genomes - plants which are hugely important in world nutrition.

"Some plants are a geneticist's nightmare," said Todd Mockler, a principal investigator on this project and assistant professor in the Department of Botany and Plant Pathology. "Wheat, for instance, is an important crop, but it has an enormous and complex genome five times larger than a human......... Posted by: Erica      Read more         Source

February 8, 2010, 8:08 AM CT

Sugar plays key role in cell division

Using an elaborate sleuthing system they developed to probe how cells manage their own division, Johns Hopkins researchers have discovered that common but hard-to-see sugar switches are partly in control.

Because these previously unrecognized sugar switches are so abundant and potential targets of manipulation by drugs, the discovery of their role has implications for new therapys for many diseases, including cancer, the researchers say.

In the January 12 edition of Science Signaling, the team reported that it focused efforts on the apparatus that enables a human cell to split into two, a complicated biochemical machine involving hundreds of proteins. Conventional wisdom was that the job of turning these proteins on and off thus determining if, how and when a cell divides fell to phosphates, chemical compounds containing the element phosphorus, which fasten to and unfasten from proteins in a process called phosphorylation.

Instead, the Johns Hopkins researchers say, there is another layer of regulation by a process of sugar-based protein modification called O-GlcNAcylation (pronounced O-glick-NAC-alation). "This sugar-based system seems as influential and ubiquitous a cell-division signaling pathway as its phosphate counterpart and, indeed, even plays a role in regulating phosphorylation itself," says Chad Slawson, Ph.D., an author of the paper and research associate in the Department of Biological Chemistry, Johns Hopkins University School of Medicine......... Posted by: Janet      Read more         Source

February 5, 2010, 8:02 AM CT

Egyptian fruit bat finds a target

New research conducted at the University of Maryland's bat lab shows Egyptian fruit bats find a target by NOT aiming their guiding sonar directly at it. Instead, they alternately point the sound beam to either side of the target. The new findings by scientists from Maryland and the Weizmann Institute of Science in Israel suggest that this strategy optimizes the bats' ability to pinpoint the location of a target, but also makes it harder for them to detect a target in the first place.

"We believe that this tradeoff between detecting a object and determining its location is fundamental to any process that involves tracking an object whether done by a bat, a dog or a human, and whether accomplished through hearing, smell or sight," said coauthor Cynthia Moss, a University of Maryland professor of psychology, who directs interdisciplinary bat echolocation research in the university's Auditory Neuroethology Lab, better known as the bat lab.

Moss, colleagues Nachum Ulanovsky and Yossi Yovel of the Weizmann Institute, and Ben Falk, a graduate student of Moss's in Maryland's Neuroscience and Cognitive Science Program, published their findings in this week's edition of the journal Science. Ulanovsky, the paper's corresponding author, was a Maryland postdoctoral student under Moss......... Posted by: Kelly      Read more         Source

February 4, 2010, 8:22 AM CT

Viagra enhances fetal growth in female sheep

A joke among two Texas AgriLife Research researchers later turned into a fully-funded study found Viagra can aid fetal development in female sheep. Female sheep (ewes) are an agriculturally important species, which can serve as an excellent animal model for studying the physiology of human pregnancy, the scientists said.

Viagra (sildenafil citrate), which is used to treat male erectile dysfunction, enhanced blood flow in pregnant female sheep, helping send vital amino acids and other nutrients needed in fetal development. The study's results not only will assist with solving fetal development problems in other livestock, but possibly in humans, said Dr. Guoyao Wu, AgriLife Research animal nutritionist and Senior Faculty Fellow in the Department of Animal Science at Texas A&M University.

"Because 5 percent to 10 percent of infants are born as low birth-weight babies worldwide, and because fetal-growth retardation is also a significant problem in livestock species, our findings have important implications for both human health and animal agriculture," Wu said.

The findings are published in a recent edition of The Journal of Nutrition (http://www.nutrition.org/).

The study originated in 2003 after a chat between Wu and fellow AgriLife Research scientist Dr. Tom Spencer when they were working with pregnant ewes......... Posted by: Kelly      Read more         Source

February 3, 2010, 7:41 AM CT

Ancient crocodile likely food source for Titanoboa

A 60-million-year-old relative of crocodiles described this week by University of Florida scientists in the Journal of Vertebrate Paleontology was likely a food source for Titanoboa, the largest snake the world has ever known.

Working with researchers from the Smithsonian Tropical Research Institute in Panama, paleontologists from the Florida Museum of Natural History on the UF campus found fossils of the new species of ancient crocodile in the Cerrejon Formation in northern Colombia. The site, one of the world's largest open-pit coal mines, also yielded skeletons of the giant, boa constrictor-like Titanoboa, which measured up to 45 feet long. This is the first reported study of a fossil crocodyliform from the same site.

"We're starting to flesh out the fauna that we have from there," said main author Alex Hastings, a graduate student at the Florida Museum and UF's department of geological sciences.

Specimens used in the study show the new species, named Cerrejonisuchus improcerus, grew only 6 to 7 feet long, making it easy prey for Titanoboa. Its scientific name means small crocodile from Cerrejon.

The findings follow another study by scientists at UF and the Smithsonian providing the first reliable evidence of what Neotropical rainforests looked like 60 million years ago......... Posted by: Kelly      Read more         Source

February 1, 2010, 7:54 AM CT

New light on our earliest fossil ancestry

Decaying corpses are commonly the domain of forensic scientists, but palaeontologists have discovered that studying rotting fish sheds new light on our earliest ancestry.

The researchers, from the Department of Geology at the University of Leicester, devised a new method for extracting information from 500 million year old fossils -they studied the way fish decompose to gain a clearer picture of how our ancient fish-like ancestors would have looked. Their results indicate that some of the earliest fossils from our part of the tree of life may have been more complex than has previously been thought.

Their findings have been published recently, Sunday Jan 31, ahead of print in Advance Online Publication (AOP) of the science journal Nature on www.nature.com The work was funded by the Natural Environment Research Council (NERC).

Dr Rob Sansom, main author of the paper explains: "Interpreting fossils is in some ways similar to forensic analysis we gather all the available clues to put together a scientific reconstruction of something that happened in the past. Unlike forensics, however, we are dealing with life from millions of years ago, and we are less interested in understanding the cause or the time of death. What we want to get at is what an animal was like before it died and, as with forensic analysis, knowing how the decomposition that took place after death altered the body provides important clues to its original anatomy."........ Posted by: Kelly      Read more         Source

February 1, 2010, 7:43 AM CT

Guilt by association

Researchers have created a new computational model that can be used to predict gene function of uncharacterized plant genes with unprecedented speed and accuracy. The network, dubbed AraNet, has over 19,600 genes associated to each other by over 1 million links and can increase the discovery rate of new genes affiliated with a given trait tenfold. It is a huge boost to fundamental plant biology and agricultural research.

Despite immense progress in functional characterization of plant genomes, over 30% of the 30,000 Arabidopsis genes have not been functionally characterized yet. Another third has little evidence regarding their role in the plant.

"In essence, AraNet is based on the simple idea that genes that physically reside in the same neighborhood, or turn on in concert with one another are probably linked to similar traits," explained corresponding author Sue Rhee at the Carnegie Institution's Department of Plant Biology. "We call it guilt by association. Based on over 50 million scientific observations, AraNet contains over 1 million linkages of the 19,600 genes in the tiny, experimental mustard plant Arabidopsis thaliana We made a map of the associations and demonstrated that we can use the network to propose that uncharacterized genes are associated with specific traits based on the strength of their associations with genes already known to be associated with those characteristics."........ Posted by: Erica      Read more         Source