November 19, 2007, 8:26 PM CT

Evolution is deterministic, not random

A multi-national team of biologists has concluded that developmental evolution is deterministic and orderly, rather than random, based on a study of different species of roundworms. The findings are published in the latest issue of the journal Current Biology.

The leading author is Karin Kiontke, a post-doctoral fellow in New York Universitys Department of Biology. The research team included NYU Biology Professor David Fitch as well as scientists from the University of Paris, the Israel Institute of Technology, and the Max-Planck Institute for Developmental Biology in Gera number of.

The scientists were interested in how development evolves in organs which themselves do not change. To do so, they examined the vulvathe female's copulatory and egg-laying organin nearly 50 species of roundworms. Because the vulva does not significantly change across species, one might predict that there would be little variation in vulva development. However, the scientists found an astonishing amount of developmental variation. They then reasoned that this variation, since it did not affect the final adult vulva, should have evolved in a stochastic, or random, fashion.

In executing the study, the research team analyzed more than 40 characteristics of vulva development, including cell death, cell division patterns, and related aspects of gonad development. They plotted the evolution of these traits on a new phylogenetic tree, which illustrates how species are correlation to one another and provides a map as to how evolutionary changes are occurring......... Posted by: Janet      Read more         Source

November 19, 2007, 8:15 PM CT

Capturing Chemical Reactions In A Single Living Cell

Bioengineers at the University of California, Berkeley, have discovered a technique that for the first time enables the detection of biomolecules' dynamic reactions in a single living cell.

By taking advantage of the signature frequency by which organic and inorganic molecules absorb light, the team of researchers, led by Luke Lee, professor of bioengineering and director of UC Berkeley's Biomolecular Nanotechnology Center, can determine in real time whether specific enzymes are activated or particular genes are expressed, all with unprecedented resolution within a single living cell.

The technique, described in the Nov. 18 issue of the journal Nature Methods, could lead to a new era in molecular imaging with implications for cell-based drug discovery and biomedical diagnostics.

The scientists point out that other techniques, such as nuclear magnetic resonance, can at best provide information about a cluster of cells. But to determine the earliest signs of disease progression or of stem cell proliferation, it's necessary to drill down deeper to the molecular dynamics within a single cell.

To study the biochemical processes of a cell, researchers currently cut through its outer membrane to separate and analyze the cellular components. That method can never provide a real-time view of how components function together because the cell is killed in the process of extracting its components......... Posted by: Janet      Read more         Source

Tue, 20 Nov 2007 01:48:41 GMT

Order Your DNA Portrait!

Deepak Singh, the author of BBGM, shared an interesting link with us through Twitter. You can get your own DNA portrait at DNA 11. In the era of personalized genetics, it’s a perfect example how industry will use these methods to explore all the financial possibilities. Here is DNA 11:

DNA 11 is the original creator of DNA Portraits-the world’s most personal form of art. We have propelled an entire industry with unique artwork based on genetic codes.

Endorsed by the Museum of Modern Art design stores in New York as innovative masterpieces, our DNA Portraits, Fingerprint Portraits and Fingerprint Portraits let you make the ultimate personal artistic statement.

How does it work?

• You order your complete DNA collection kit.
• Collect a cheek cell swab using the swab they provide.
• Send the sample to them.
• And you get this:

Would you like one above your bed?

Fingerprint Portraits Posted by: Bertalan      Read more     Source

November 18, 2007, 8:51 PM CT

genomes of 12 fly species

In work that reveals important clues in the evolution of genes, an international consortium of MIT scientists and colleagues has analyzed the genomes of twelve species of the fruit fly Drosophila in one of the first large-scale comparisons of multiple animal genomes.

The researchers' approach may also help unlock the secrets of other genomes, including our own.

The work appears in the Nov. 8 issue of Nature and in more than 40 accompanying papers in Genome Research and other journals.

"Having the sequences of many closely related species allows us to study the evolutionary forces that have shaped the fruit fly's family tree, and to discover the working parts of the fly genome in a systematic way," said Manolis Kellis, associate member of the Broad Institute of MIT and Harvard and one of the project leaders. Kellis is also the Karl Van Tassel Career Development Assistant Professor of Electrical Engineering and Computer Science at MIT, and is affiliated with the Institute's Computer Science and Artificial Intelligence Laboratory.

On one hand, the researchers studied the differences across species to help elucidate how evolution has shaped fly biology over millions of years. Their analysis revealed that while many attributes of Drosophila genomes are in fact conserved across multiple species, each species has novel features not seen in any other. For example, the genes involved in interactions with the environment and in reproduction showed signs of adaptive evolution, meaning that they likely provided some survival advantage to the organism......... Posted by: Janet      Read more         Source

November 15, 2007, 10:15 PM CT

Plant Shows Significance of Maternal Effects

When habitat changes, animals migrate. But how do immobile organisms like plants cope when faced with alterations to their environment? This is an increasingly important question in light of new environmental conditions brought on by global climate change.

A University of Virginia study, reported in the Nov. 16 issue of the journal Science, demonstrates that plants grown in the same setting as their maternal plant performed almost 3½ times better than those raised in a different environment - indicating that maternal plants give cues to their offspring that help them adapt to their environmental conditions.

Evolutionary biologist Laura Galloway, an associate professor of biology at the University of Virginia, recently completed a study of the American bellflower, a native wildflower that usually grows in both shaded areas and areas that receive full sunlight for at least part of the day. She focused on the transmission of environmental information between maternal plants and their offspring.

Galloway planted some seeds in light conditions similar to their maternal plants and some in different light. She observed that plants growing in the same setting as their maternal plant outperformed those planted in a different environment. The work was conducted in a natural habitat at the University of Virginia's Mountain Lake Biological Station in Southwest Virginia......... Posted by: Erica      Read more         Source

November 15, 2007, 10:10 PM CT

Cutting-edge DNA 'fin-printing' project for salmon

Some salmon make one heck of a commute.

The record holder in the Pacific Northwest, for example, is a steelhead that was tagged in the Clearwater River, Idaho, in April 2003. A year and a half later, it was caught off the southern Kuril Islands near Japan. The most direct route between those two points as the crow flies, as they say is 4,200 miles. Imagine fish that make it that far then turn around and travel back to their home streams in order to spawn.

The ability of salmon to migrate such extraordinary distances makes it hard at a management level to know whose fish are whose and at a biological level to unravel the mystery of their ocean migration.

A $4.1 million effort just launched by the University of Washington's School of Aquatic and Fishery Sciences aims to help by gathering genetic information for thousands upon thousands of Pacific Rim salmon populations and creating open-access databases for managers, treaty-makers and scientists.

Jim and Lisa Seeb, known for their groundbreaking work identifying salmon populations using genetic markers, joined the UW this fall as research professors. Genetic markers are key bits of a fish's DNA that, when in comparison to the same spots on the DNA of other fish, can reveal if they are from the same population or not......... Posted by: Kelly      Read more         Source

November 14, 2007, 9:56 PM CT

Gene in male fish lures females

A gene has been found in male cichlid fish that evolved to lure female fish so that male cichlids can deposit sperm in the females mouths. A study in the online open access journal BMC Biology reveals that the gene is linked to egg-like markings on the fins of cichlid fishes and uncovers the evolutionary history of these markings, which are central to the success of the fishes' exotic oral mating behaviour.

Walter Salzburger, Ingo Braasch and Axel Meyer reared 19 cichlid species at Konstanz University in Gera number of and identified a gene involved in producing yellow pigment cells in oval spots on the fishes' fins. These markings, known as egg-dummies, are found on the anal fins of the male fish and are crucial to mating. The fish are known as maternal mouthbrooders, because once the female has laid her eggs, she picks them up in her mouth. Attracted by what she takes to be eggs - actually the egg-dummy markings - the female then approaches the male. When the female is close to the anal fin, the male discharges sperm into the female's mouth to fertilize the eggs.

Cichlids are a family of fish that include tilapia and angel fish. There are more than 1,800 cichlid species found only in East Africa, and more than 80% of these belong to a grouping known as the haplochromines, which show the characteristic egg dummies......... Posted by: Kelly      Read more         Source

November 14, 2007, 9:36 PM CT

Primary rain forest is irreplaceable

As world leaders prepare to discuss conservation-friendly carbon credits in Bali and a regional initiative threatens a new wave of deforestation in the South American tropics, new research from the University of East Anglia and Brazil's Goeldi Museum highlights once again the irreplaceable importance of primary rain forest.

Working in the north-eastern Brazilian Amazon the international team of researchers undertook the single-largest assessment of the biodiversity conservation value of primary, secondary and plantation forests ever conducted in the humid tropics. The study was partly funded by the UK Government's Darwin Initiative and their findings are published in the latest edition of the Proceedings of the National Academy of Sciences (PNAS).

Over an area larger than Wales, the UEA and museum scientists surveyed five primary rain forest sites, five areas of natural secondary forest and five areas planted with fast-growing exotic trees (Eucalyptus), to evaluate patterns of biodiversity.

Following an intensive effort of more than 20,000 scientist hours in the field and laboratory, they collected data on the distribution of 15 different groups of animals (vertebrates and invertebrates) and woody plants, including well-studied groups such as monkeys, butterflies and amphibians and also more obscure species such as fruit flies, orchid bees and grasshoppers......... Posted by: Erica      Read more         Source

November 14, 2007, 9:34 PM CT

Evolution of strange amphibian breeding habits

Parasites can decimate amphibian populations, but one University of Georgia researcher believes they might also play a role in spurring the evolution of new and sometimes bizarre breeding strategies.

Brian Todd, a researcher at the UGA Odum School of Ecology Savannah River Ecology Lab, explains that most amphibians start their lives in water (tadpoles are a good example), and then make their way onto land as adults and return to the water to breed. But there are other breeding strategies as well. Take, for instance, the Darwin's frog, the species that swallows its eggs and, a few weeks later, regurgitates its young. Or the marsupial frog, a species that carries its eggs on its back until they hatch. Several species lay eggs in small puddles on land or high up in trees where they hatch as miniature versions of adults, bypassing the larval stage entirely.

Researchers have hypothesized that natural selection favored these non-traditional breeding strategies as a way to avoid predatory fish or the risk of a breeding pond or stream drying up. In a review article published in the recent issue of The American Naturalist, Todd argues that the diversity of reproductive strategies that amphibians employ might also be influenced by the benefits that come from avoiding viruses, fungi and other parasites......... Posted by: Kelly      Read more         Source

November 14, 2007, 8:55 PM CT

Differences between humans and chimps

Scientists are closer to understanding why humans differ so greatly from chimpanzees in the way they look, behave, think, and fight off disease, despite having genes that are nearly 99% identical.

Innovative research from the University of Torontos Centre for Cellular and Biomolecular Research has uncovered potential new explanations for these glaring differences. In comparing brain and heart tissue from humans and chimpanzees, U of T Professor Benjamin Blencowe and his team, including graduate student researcher John Calarco, have discovered significant differences in the way genetic material is spliced to create proteins.

Its clear that humans are very different from chimpanzees on several levels, but we wanted to find out if it could be the splicing process that accounts for some of these fundamental differences, says Blencowe, a professor with the Banting and Best Department of Medical Research and Department of Molecular Genetics. The surprising thing we found was that six to eight per cent of the alternative splicing events we looked at were showing differences, which is quite significant. And those genes that showed differences in splicing are linked to a range of important processes, including susceptibility to certain diseases.

Splicing is the process by which the coding regions of genes are joined to generate genetic messages that specify the production of proteins, the key structural and functional constituents of cells. Splicing can occur in alternative ways in the same genetic message to generate more than one type of protein. The new findings reveal that the alternative splicing process differs significantly between humans and chimpanzees......... Posted by: Kelly      Read more         Source