Today in the News (June 26, 2009)

Evolution

Here's some interesting news on the subject of genetics from Science Daily (June 26, 2009):

Gene Evolution Process Discovered

One of the mechanisms governing how our physical features and behavioural traits have evolved over centuries has been discovered by researchers at the University of Leeds.

Darwin proposed that such traits are passed from a parent to their offspring, with natural selection favouring those that give the greatest advantage for survival, but did not have a scientific explanation for this process.

In new research the Leeds team reports that a protein known as REST plays a central role in switching specific genes on and off, thereby determining how specific traits develop in offspring.

The study shows that REST controls the process by which proteins are made, following the instructions encoded in genes. It also reveals that while REST regulates a core set of genes in all vertebrates, it has also evolved to work with a greater number of genes specific to mammals, in particular in the brain – potentially playing a leading role in the evolution of our intelligence.

Says lead researcher Dr Ian Wood of the University's Faculty of Biological Sciences: "This is the first study of the human genome to look at REST in such detail and compare the specific genes it regulates in different species. We've found that it works by binding to specific genetic sequences and repressing or enhancing the expression of genes associated with these sequences.

"Scientists have believed for many years that differences in the way genes are expressed into functional proteins is what differentiates one species from another and drives evolutionary change – but no-one has been able to prove it until now."

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Vaccines

Here's another interesting news item from Science Daily (June 26, 2009); this time on the subject of vaccines:

New Images May Improve Vaccine Design For Deadly Rotavirus

Howard Hughes Medical Institute researchers are reporting the first detailed molecular snapshots of a deadly gastrointestinal virus as it is caught in the grasp of an immune system molecule with the capacity to destroy it. The images could help scientists design a more effective vaccine against rotavirus, a lethal infection that kills more than 500,000 children worldwide each year. The discovery is timely.

Last week the World Health Organization recommended that rotavirus vaccination be included in all national immunization programs worldwide. Virtually every child in the world becomes infected with rotaviruses before developing natural immunity. But each year an estimated two million children are hospitalized because rotavirus infection results in severe dehydration caused by diarrhea and vomiting.

Both natural and vaccine-induced immunity occur only after the immune system has "seen" the virus and generates neutralizing antibodies. These soldiers of the immune system seek out and attach to rotavirus particles, rendering them unable to infect cells.

In the new experiments, Howard Hughes Medical Institute (HHMI) researchers have mapped the structure of an antiviral antibody clamped onto a protein called VP7 that stipples the surface of rotavirus. The structural map reveals intimate new details about how the antibody interferes with VP7, a protein that helps the virus infect cells. The information may be useful in designing a new generation of rotavirus vaccines that could be easier to store and administer than current vaccines, said the researchers.

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