Life Sciences

Cryptococcus neoformans is a major cause of fungal meningitis, predominantly in immunocompromised individuals. This fungus has two mating types/sexes, a and α, and mating typically requires two individuals with opposite mating types. It is mysterious why the α mating type is overwhelmingly predominant in nature and how the capacity for sexual reproduction is maintained in a largely unisexual population. We postulated that same-sex mating between α isolates may occur naturally, as it does under laboratory conditions. By analyzing natural Cryptococcus diploid hybrid isolates containing two α…

Help with assigning gender could one day be at hand for intersex individuals whose genital phenotypes and sex chromosomes don't match, thanks to the discovery of a stable sex hormone signature in our cells. Researchers have shown for the first time that testosterone leaves an irreversible molecular signature in cells that may provide a far more sophisticated way to look at sex than just ascertaining the presence of the Y chromosome. A team of researchers from the US and Germany were able to pinpoint the role of testosterone by comparing individuals with complete androgen insensitivity…

Abuse of psychostimulants such as amphetamine remains a serious public health concern. Amphetamines mediate their behavioral effects by stimulating dopaminergic signaling throughout reward circuits of the brain. This property of amphetamine relies on its actions at the dopamine transporter (DAT), a presynaptic plasma membrane protein responsible for the reuptake of extracellular dopamine. Recently, researchers have revealed the novel ability of insulin signaling pathways in the brain to regulate DAT function as well as the cellular and behavioral actions of amphetamine. In a new study…

The genome analysis of this tiny green alga has uncovered hundreds of genes that are uniquely associated with carbon dioxide capture and generation of biomass. Among the 15,000-plus genes revealed in the study are those that encode the structure and function of the specialized organelle that houses the photosynthetic apparatus, the chloroplast, which is responsible for converting light to chemical energy. The genome also provides a glimpse back through time to the last common ancestor of plants and animals. The single-celled alga Chlamydomonas reinhardtii, while less than a thousandth of an…

Red wine is known to have multiple health benefits. Researchers at the University of Missouri-Columbia have found that red wine may also protect humans from common food-borne diseases, even E. coli. Researchers Azlin Mustapha, associate professor of food science in the College of Agriculture and doctoral student Atreyee Das are conducting on-going studies examining the inhibitory effects of red wines and grape juice against pathogens and probiotic bacteria, which naturally reside in the intestinal tract and can be beneficial in combating, among other things, high cholesterol and tumors.…

Duke University Medical Center researchers believe they have discovered why the appendix exists and what purpose it serves in modern humans. They think it is used to 'reboot' the digestive system and produce the bacteria sometimes eliminated by disease. How is it that people have them removed and live normal lives afterward? In modern times, it is relatively unimportant. In crowded areas people can easily replace lost bacteria from contact with others but in ancient times, when isolation was more common or when diseases such as cholera or amoebic dysentery struck and eliminated the stomach'…

Thousands of new kinds of marine microbes have been discovered at two deep-sea hydrothermal vents off the Oregon coast by scientists at the MBL (Marine Biological Laboratory) and University of Washington’s Joint Institute for the Study of Atmosphere and Ocean. Their findings, published in the October 5 issue of the journal Science, are the result of the most comprehensive, comparative study to date of deep-sea microbial communities that are responsible for cycling carbon, nitrogen, and sulfur to help keep Earth habitable. Using a new analytical technique called “454 tag sequencing,” the…

Bronchopulmonary Dysplasia (BPD) occurs in 20-40% of infants born below 2.5 lbs. and before 28 weeks of gestation, and means babies still need supplemental oxygen at 36 weeks postmenstrual age. It is the second leading cause of death among infants born within this gestational age and is characterised by inflammation and scarring in the lungs. Diagnosing a risk of fatal lung disorders may be possible by analysing the umbilical cords of premature babies, according to research published in the online open access journal Genome Biology. Until now, paediatricians have not been able to predict the…

“Survival of the fittest” has popularly described evolution for more than a century, but a new study published in the Royal Society journal Biology Letters provides further evidence that random genetic mutations over millions of years may also play a powerful role. Florida and California scientists are the first to link the evolution of proteins — the organic compounds that determine the structure and function of living things — to a species’ metabolic rate. Across species from fish to mammals, they found that rates of protein evolution showed the same body size and temperature dependence as…

The present can tell you a lot about the past, but you need to know where to look. A new study appearing this month in Genome Research reveals that protein architectures – the three-dimensional structures of specific regions within proteins – provide an extraordinary window on the history of life. In the study, researchers at the University of Illinois describe contemporary protein architectures as “molecular fossils” or “historical imprints” that mark important milestones in evolutionary history. The research team compiled a global census of protein architectures, and used these relics to…