Algae are distributed widely on the earth, from land to ocean, from freshwater to saline water, and from the polar to the tropical regions. Algae have been part of Chinese food for thousands of years. They were used as Chinese traditional medicine and cited in Chinese literatures as early as 2500 years ago. Since 1949 China has successfully established the largest seaweed cultivation industry in the world.
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A species of fruit fly from the Seychelles Islands often lays larvae instead of eggs, UC San Diego biologists have discovered. Clues to how animals switch from laying eggs to live birth may be found in the well-studied species' ecology and genes.
The fly is one of a dozen species of Drosophila to have recently had their genomes sequenced, information that should provide abundant opportunities for identifying genetic changes that cause females of this species, and not others, to retain their fertilized eggs until they are ready to hatch.
How many mouths does a plant need in order to survive? The answer changes depending on climate, and some of the decisions are made long before a new leaf sprouts.
Stanford researchers have found that the formation of microscopic pores called stomata (derived from the Greek word stoma, meaning mouth) is controlled by a specific signaling pathway that blocks activity of a single protein required for stomata development. The findings are described in a paper published Nov. 14 in Science.
CORVALLIS, Ore. – If you're a cancer cell, you want a protein called Bcl-2 on your side because it decides if you live or die. It's usually a trusted bodyguard, protecting cancer cells from programmed death and allowing them to grow and form tumors. But sometimes it turns into their assassin.
Scientists knew it happened, but they didn't know how to actually cause such a betrayal. Now they do. And it may lead to the development of new cancer-fighting drugs.
Scientists at Penn State have shed light on some of the processes that regulate genes -- such as the processes that ensure that proteins are produced at the correct time, place, and amount in an organism -- and they also have shed light on the evolution of the DNA regions that regulate genes. The team focused on regulatory regions that, when bound to the protein GATA1, are thought to turn on genes that play an important role in the development of red blood cells.
A trial of peer-led sex education in schools in England has found that it is not more effective at reducing teenage abortions than the sex education classes given by teachers. However, the study, published in the open access journal PLoS Medicine, does show that a peer-led approach to sex education is preferred by pupils and suggests it should still be considered as part of a broad strategy to reduce teenage pregnancy.
In low-transmission areas, if widely used, artemisinin combination therapy (ACT) may reduce malaria transmission as effectively as the widespread use of insecticide-treated bed nets, says a new study published in next week's PLoS Medicine. The study also finds that the use of longer-acting anti-malarial regimens with or without artemisinin components may be an effective way to reduce transmission in high-transmission areas, provided the development of parasite resistance can be avoided.
A provocative debate in this week's PLoS Medicine examines whether the private sector should step up its involvement in delivering health care in low-income countries.
These countries suffer a disproportionate burden of disease, and often struggle with weak health systems. Both the public and private sector deliver health care in these countries, but the appropriate role for each of these sectors in health system strengthening remains controversial.
In this week's issue of PLoS Biology, a team of Marseilles University lecturers led by Pascal Hingamp, describe the Annotathon – an innovative bioinformatics teaching approach that appeals to undergraduate biology students. With an increasing interest in metagenomics – the decoding of not just a single genome, but of an entire microbial ecosystem – the amount of data produced is more than a biologist can keep up with. Because of this, Bioinformatics – the use of computer techniques to process biological data – is becoming more popular.
Starving "social amoebas" seek the support of genetically similar "kin" when they form multi-cellular organisms to ensure survival, researchers from Baylor College of Medicine and Rice University in Houston report in a paper published today in the open-access journal PLoS Biology.
A quarter of drug trials submitted in support of new drug applications to the US Food and Drug Administration (FDA) remain unpublished five years after the fact, says new research published in the open access journal PLoS Medicine.
If you have had a hard day at work, you may change your eating habits, perhaps favoring comfort food, but you don't suddenly develop the ability to eat the plate and cutlery. A new paper, published in this week's issue of PLoS Biology, describes an evolutionary mechanism in yeast that allows cells to respond to environmental stress in novel ways, including digesting materials that they were previously unable to use – though admittedly, they aren't eating crockery just yet!
CAMBRIDGE, Mass. (November 25, 2008) – Under stress, yeast cells can unleash a remarkable mechanism based on protein-misfolding that gives them new characteristics without requiring genetic mutations.
Researchers in Whitehead Member Susan Lindquist's lab now have shown that this mechanism is triggered much more often as the cells undergo stress, suggesting that it is tailored to play exactly this role in evolution.
The mechanism is based on a prion—a protein misfolded into an unusual configuration that can change its function within a cell.
Artemisinin combination therapies (ACTs) could be almost as effective in reducing transmission of malaria as insecticide-treated bednets (ITNs) in areas of low transmission, a study based on data from Tanzania has found. In high transmission areas, long-acting antimalarial regimens may be needed to achieve significant transmission reductions.
Contrary to common scientific belief, the length of a sperm's tail does not always determine how fast it can swim. Research published in the open access journal BMC Evolutionary Biology has shown that in the counter-intuitive microscopic world in which sperm operate, streamlining and longer tails don't always provide a speed advantage.