Genetics & Molecular Biology

The DNA in our cells is folded into millions of small packets, like beads on a string, allowing two-meter linear DNA genomes to fit into a nucleus of only about 0.01 mm in diameter.

However, these molecular beads, called nucleosomes, render DNA 'unreadable'. They thus need to be temporarily displaced to allow genes to be copied ('transcribed') into the messages that are used to make proteins. How cells ensure appropriate access to 'promoter' DNA, the regions where gene transcription begins, is still poorly understood.


10 commercially available insect repellents were evaluated for their effectiveness at repelling mosquitoes. Three of the products (Repel 100® Insect Repellent, OFF® Deep Woods Insect Repellent VIII, and Cutter® Skinsations Insect Repellent) were mosquito repellents that contained DEET as the active ingredient, and four of the products (Cutter® Natural Insect Repellent, EcoSmart® Organic Insect Repellent, Cutter® Lemon Eucalyptus Insect Repellent, and Avon® Skin So Soft Bug Guard) were mosquito repellents that did not contain DEET. The other three products tested were Avon® Skin So Soft Bath Oil, Victoria's Secret® Bombshell perfume, and Mosquito Skin Patch®, a skin patch with vitamin B1 as the active ingredient.


The lipid ceramide, long known to help keep skin smooth, also helps algae swim toward the light and appears to enable one type of brain cell to keep cerebrospinal fluid moving, researchers report in a new paper. 

Ceramide helps make and keep in motion hairlike projections called motile cilia found in algae and in brains. 

"It's important to know how you regulate your cilia because they can become dysfunctional by stroke, by Alzheimer's, by inflammation, even by aging," said Dr. Erhard Bieberich, neuroscientist in the Medical College of Georgia Department of Neuroscience and Regenerative Medicine.


Human embryonic stem cells (hESCs) technology has been around since the late 1990s and became a political football in the early 2000s when President George W. Bush made federal funding for it available for the first time, but limited it to existing lines, which made the NIH happy but was quickly pounced on by his opponents as a "ban."


Approximately five percent of people suffers an epileptic attack, during which the nerve cells get out of their usual rhythm and fire in a very rapid frequency, over the course of their lives. This results in seizures and such synchronous discharges in the brain occur most frequently in the temporal lobe.

Often, a seizure disorder develops after a delay following transient brain damage - for example due to injury or inflammation. So-called ion channels are involved in the transfer of signals in the brain; these channels act like a doorman to regulate the entry of calcium ions in the nerve cells.

Researchers have discovered how a protein from malaria could some day help stop cancer.

While exploring why pregnant women are particularly susceptible to malaria, they found that the mosquito-borne parasite that causes malaria also produces a protein that binds to a particular type of sugar molecule in the placenta. 


The identification of a protein that selectively clears damaged chloroplasts from plant cells reveals how plants maintain a "clean workshop" during the process of photosynthesis. Chloroplasts play an important role in transforming light into useable energy for plants, but when these energy powerhouses are damaged, they release harmful substances. When the plant detects this damage, signals are sent to genes involved in chloroplast function and stress adaptation.


A single blood test could reveal whether an otherwise healthy person is unusually likely to die of pneumonia or sepsis within the next 14 years.

Based on an analysis of 10,000 individuals, researchers have identified a molecular byproduct of inflammation, called GlycA, which seems to predict premature death due to infections.

The findings, published October 22 in Cell Systems, suggest that high GlycA levels in the blood indicate a state of chronic inflammation that may arise from low-level chronic infection or an overactive immune response. That inflammation damages the body, which likely renders individuals more susceptible to severe infections.


Delivering the hormone leptin directly to the brain through gene therapy can aid weight loss without the significant side effect of bone loss, according to new research.

Rapid or significant weight loss through dieting can trigger bone loss. Loss of bone density, in turn, can lead to increased susceptibility to bone fractures in older adults, which can have a debilitating effect on quality of life.

The bone loss is most concerning in people whose weight fluctuates due to "yo-yo" dieting, or repeated cycles of weight gain and loss, because bone lost during weight loss is not typically regained when the person gains weight again, said Urszula Iwaniec, an associate professor in the College of Public Health and Human Sciences at Oregon State University.


When a Lake Malawi cichlid loses a tooth, a new one drops neatly into place as a replacement. Why can't humans similarly regrow teeth lost to injury or disease?

Working with hundreds of these colorful fish, researchers are beginning to understanding how the animals maintain their hundreds of teeth throughout their adult lives. By studying how structures in embryonic fish differentiate into either teeth or taste buds, the researchers hope to one day be able to turn on the tooth regeneration mechanism in humans - which, like other mammals, get only two sets of teeth to last a lifetime.