Genetics & Molecular Biology

Researchers have identified factors that spark the formation of pluripotent cells. Their findings, published in Developmental Cell, shed light on human embryonic development and help research into cell reprogramming and assisted conception. Embryonic stem cells are widely known for their ability to differentiate into any cell type - a state called pluripotency. This state is short lived in the embryo, but is essential to normal development. In this study, the researchers mapped when and where genes were expressed (turned on or off) during early development of the mouse and common marmoset, a…

The 2015 growing season was tough on tomato plants at the Boyce Thompson Institute, as bacterial speck disease (Pseudomonas syringae pv. tomato) descended on their field. But it was all done on purpose. Don't go crazy and start calling up donors for more money, Natural Resources Defense Council, scientists are not creating World War Z. It was done on purpose and the bacteria is completely organic - and those infected plants may help science save others from a similar, spotted fate. Cool weather and heavy rains in early summer created the perfect environment for speck--a bacterial disease that…

DNA represents a dynamic form of information, balancing efficient storage and access requirements. Packaging approximately 1.8m of DNA into something as small as a cell nucleus is no mean feat, but unpacking it again to access the required sections and genes? That requires organization. In a nutshell, this is achieved through DNA condensed and packaged as chromatin, a complex of DNA and proteins called histones, which is constantly modified as the DNA is accessed. The histone proteins need constant replacement to maintain the correct chromatin structure required for all DNA related processes…

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. Researchers from the University of Geneva (UNIGE) and the Ecole…

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…

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…

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." From 1998 until 2007 hESCs were the only human cells known with the potential to become any other type of cell in the body. Then Shinya Yamanaka discovered how to engineer adult somatic cells to a state where they, too, had this potential -- a discovery for…

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…

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.  Researchers found that the same type of sugar molecule also is present in many types of cancer. They realized that the sugar molecule -- oncofetal chondroitin sulfate -- could be a target for anti-cancer drugs, and that the malarial protein, called VAR2CSA, could provide…

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. Some evidence suggests that plastid ferrochelatases 1 and 2 (FC1 and FC2), enzymes that convert protoporphyrin-IX (Proto) to heme,…