Biology articlesScientists uncover evidence of a 'memory code'
By examining how sounds are registered during the process of learning, UC Irvine neurobiologists have discovered a neural coding mechanism that the brain relies upon to register the intensity of memories based on the importance of the experience.
First glimpse at how plants, most animals repair UV-damaged DNA
For the first time, researchers have observed exactly how some cells are able to repair DNA damage caused by the sun's ultraviolet (UV) radiation. The Ohio State University study revealed how the enzyme photolyase uses energy from visible light to repair UV damage.
Immune system has evolved to prevent autoimmune disease
New research finds the human immune system has foregone evolutionary changes that would allow it to produce better antibodies in less time because the improved antibodies would be far more likely to attack the body's own tissues. The Rice University study finds the immune system has evolved a near-perfect balance for producing antibodies that are both effective against pathogens and unlikely to cause autoimmune disease.
Life origins were easier than was thought
In the primordial soup that produced life on earth, there were organic molecules that combined to produce the first nucleic acid chains, which were the first elements able to self-replicate.
A new view on the evolution of the eye lens
The evolution of complex and physiologically remarkable structures such as the vertebrate eye has long been a focus of intrigue and theorizing by biologists. In work reported this week in Current Biology, the evolutionary history of a critical eye protein has revealed a previously unrecognized relationship between certain components of vertebrate eyes and those of the more primitive light-sensing systems of invertebrates.
Researchers predict infinite genomes
Ever since the genomics revolution took off, scientists have been busily deciphering vast numbers of genomes. Cataloging. Analyzing. Comparing. Public databases hold 239 complete bacterial genomes alone.
New research could help us deliver genes for new bone formation
UK scientists are working on new methods to regenerate cartilage and bone by delivering genes to stem cells within the body to instruct them to turn into bone cells. The research, funded by the Biotechnology and Biological Sciences Research Council (BBSRC), could lead to a new approach to tissue engineering. With the ageing populations of Western countries it holds the potential of significant benefits for patients needing joint replacement or similar treatments.
Researchers uncover E. coli's defense mechanism
Researchers at the Georgia Institute of Technology and the John Innes Centre in the United Kingdom have uncovered a mechanism with which disease-causing bacteria may thwart the body's natural defense responses. The findings, which could ultimately lead to the development of more effective antibiotics, appear in the September 29, 2005 issue of the journal Nature.
Oxygen increase caused mammals to triumph
The first, high resolution continuous record of oxygen concentration in the earth's atmosphere shows that a sharp rise in oxygen about 50 million years ago gave mammals the evolutionary boost they needed to dominate the planet, according to Paul Falkowski, Rutgers professor of marine science and lead author of a paper published Sept. 30 in the journal Science.
Evolutionary conservation of a mechanism of longevity from worms to mammals
Though the study of aging in the nematode model organism C. elegans has provided much insight into this complex process, it is not yet clear whether genes involved in aging in the worm have a similar role in mammals. In a recent study, Dr. Hekimi and colleagues of McGill University (Canada) report that inactivation of the gene mclk1, the murine ortholog of the C. elegans gene clk-1, results in increased cellular fitness and prolonged lifespan in mice.
Genomes of more than 200 human flu strains reveal a dynamic virus
In the first large-scale effort of its kind, researchers have determined the full genetic sequence of more than 200 distinct strains of human influenza virus. The information, being made available in a publicly accessible database, is expected to help scientists better understand how flu viruses evolve, spread and cause disease. The genomic data already has enabled scientists to determine why the 2003-4 annual influenza vaccine did not fully protect individuals against the flu that season.
Biomedical engineer shows how people learn motor skills
Practice makes perfect when people learn behaviors, from baseball pitching to chess playing to public speaking. Biomedical engineers at Washington University in St. Louis have now identified how people use individual experiences to improve performance.
Rhythm gene discovered
University of Utah biologists found a gene that controls rhythmic events in a worm's life: swallowing food, laying eggs and pooping.
Satellite technology allows scientists to track warm sharks in cold polar seas
Electronic tags broadcasting from the dorsal fins of salmon sharks reveal that these top predators migrate from the glacial waters of Alaska to the warm seas off Hawaii, according to a new study in the journal Science. The salmon shark's ability to survive such a broad range of thermal conditions is attributed to high levels of specialized proteins that keep its heart muscle cells beating at very low temperatures, say the study's authors.
Newly evolved genes adopt a variety of strategies to remain in the gene pool
When Mother Nature creates an identical copy of a gene in an organism's genome, the duplicated copy is usually deleted, inactivated, or otherwise rendered nonfunctional in order to prevent genetic redundancy and to preserve biological homeostasis. In some cases, however, gene duplicates are maintained in a functional state. Until now, the biological and evolutionary forces behind the maintenance of these duplicates as functional components of the genome have remained unclear.
Hair-raising stem cells identified
Using an animal model, a research team led by Yann Barrandon at the EPFL (Ecole Polytechnique Federale de Lausanne) and the CHUV (Lausanne University Hospital) has discovered that certain cells inside the hair follicle are true multipotent stem cells, capable of developing into the many different cell types needed for hair growth and follicle replacement.
Mother nature's weapon of mass destruction? Red leaves
Scientists have long agreed that the decomposition of chlorophyll is largely responsible for the vibrant hues of most foliage in the fall. But the anthocyanin molecules that give some leaves their red tint could serve a more Darwinian purpose, according to Colgate University biology professor Frank Frey and former student Maggie Eldridge: They could be the trees' own form of chemical warfare.
Seaweed yields new compounds with pharmaceutical potential
Researchers have discovered 10 new molecular structures with pharmaceutical potential in a species of red seaweed that lives in the shallow coral reef along the coastline of Fiji in the south Pacific Ocean.
Study shows 'junk' DNA has evolutionary importance
Genetic material derisively called "junk" DNA because it does not contain the instructions for protein-coding genes and appears to have little or no function is actually critically important to an organism's evolutionary survival, according to a study conducted by a biologist at UCSD.
Based on body size, bacteria and elephants have similar metabolism
Life scientists have long maintained that, based on body size, small organisms are more metabolically active than large organisms. But a new study led by Bai-Lian Li, professor of ecology at UC Riverside, shows that this is true only for organisms that are closely related evolutionarily and have body masses differing by no more than 6-7 orders of magnitude – about the difference in body mass between an elephant and a shrew.