Archive for December 2011
Posted December 24, 2011on:
Anyone who’s passed basic biology knows that we get one copy of a gene from our mother, a second from our father. But few people realize that not all of these genes end up being treated equally. Imprinted genes are expressed from only the maternal or paternal allele, rather than both. And, when this process goes wrong, it can actually lead to diseases. Now, researchers have identified a possible way to treat imprinting errors.
In the brain, Ube3a is an imprinted gene; only the maternal allele is expressed, even if it is mutated and the paternal allele is normal. This is the case in Angelman syndrome, a severe neurodevelopmental disorder caused by mutation or deletion of the maternal allele of Ube3a. Ube3a is imprinted only in the brain, though; in other tissues, the paternal allele is expressed along with the maternal one.
This led Benjamin Philpot and his colleagues at UNC Chapel Hill to wonder: wouldn’t it be great if we could get the normal, paternal version of Ube3a to work in the brain—to unsilence it? Maybe this could help kids with Angelman syndrome.
A mysterious bony growth found in elephants’ feet is actually a sixth “toe”, scientists report.
For more than 300 years, the structure has puzzled researchers, but this study suggests that it helps to support elephants’ colossal weight.
Fossils reveal that this “pre-digit” evolved about 40 million years ago, at a point when early elephants became larger and more land-based.
The research is published in the journal Science.
Lead author Professor John Hutchinson, from the UK’s structure and motion laboratory at the Royal Veterinary College, said: “It’s a cool mystery that goes back to 1706, when the first elephant was dissected by a Scottish surgeon.”
Posted December 23, 2011on:
The computer assisted design (CAD) tools that made it possible to fabricate integrated circuits with millions of transistors may soon be coming to the biological sciences. Researchers at the U.S. Department of Energy (DOE)’s Joint BioEnergy Institute (JBEI) have developed CAD-type models and simulations for RNA molecules that make it possible to engineer biological components or “RNA devices” for controlling genetic expression in microbes. This holds enormous potential for microbial-based sustainable production of advanced biofuels, biodegradable plastics, therapeutic drugs and a host of other goods now derived from petrochemicals.
“Because biological systems exhibit functional complexity at multiple scales, a big question has been whether effective design tools can be created to increase the sizes and complexities of the microbial systems we engineer to meet specific needs,” says Jay Keasling, director of JBEI and a world authority on synthetic biology and metabolic engineering. “Our work establishes a foundation for developing CAD platforms to engineer complex RNA-based control systems that can process cellular information and program the expression of very large numbers of genes. Perhaps even more importantly, we have provided a framework for studying RNA functions and demonstrated the potential of using biochemical and biophysical modeling to develop rigorous design-driven engineering strategies for biology.” Read the rest of this entry »