A Momentary Flow

Hoping to give new meaning to the term “natural light,” a small group of biotechnology hobbyists and entrepreneurs has started a project to develop plants that glow, potentially leading the way for trees that can replace electric streetlamps and potted flowers luminous enough to read by.

The project, which will use a sophisticated form of genetic engineering called synthetic biology, is attracting attention not only for its audacious goal, but for how it is being carried out.

Rather than being the work of a corporation or an academic laboratory, it will be done by a small group of hobbyist scientists in one of the growing number of communal laboratories springing up around the nation as biotechnology becomes cheap enough to give rise to a do-it-yourself movement.

The project is also being financed in a D.I.Y. sort of way: It has attracted more than $250,000 in pledges from about 4,500 donors in about two weeks on the Web site Kickstarter. (via A Dream of Glowing Trees Is Assailed for Gene-Tinkering - NYTimes.com)

A run of poor sleep can have a dramatic effect on the internal workings of the human body, say UK researchers.

The activity of hundreds of genes was altered when people’s sleep was cut to less than six hours a day for a week.

Writing in the journal Proceedings of the National Academy of Sciences, the researchers said the results helped explain how poor sleep damaged health.

Heart disease, diabetes, obesity and poor brain function have all been linked to substandard sleep.

What missing hours in bed actually does to alter health, however, is unknown.

So researchers at the University of Surrey analysed the blood of 26 people after they had had plenty of sleep, up to 10 hours each night for a week, and compared the results with samples after a week of fewer than six hours a night.

More than 700 genes were altered by the shift. Each contains the instructions for building a protein, so those that became more active produced more proteins - changing the chemistry of the body.

Meanwhile the natural body clock was disturbed - some genes naturally wax and wane in activity through the day, but this effect was dulled by sleep deprivation.

Prof Colin Smith, from the University of Surrey, told the BBC: “There was quite a dramatic change in activity in many different kinds of genes.” (via BBC News - Bad sleep ‘dramatically’ alters body)

The creature that gave rise to all the placental mammals - a huge group that includes whales, elephants, dogs, bats and us - has at last been pinpointed.

An international effort mapped out thousands of physical traits and genetic clues to trace the lineage.

Their results indicate that all placental mammals arose from a small, furry, insect-eating animal.

A report in Science resolves the debate as to when the creature lived; it came about after the demise of dinosaurs.

That had been a hotly debated question over years of research.

Placental mammals - as opposed to the kind that lay eggs, such as the platypus, or carry young in pouches, such as the kangaroo - are an extraordinarily diverse group of animals with more than 5,000 species today. They include examples that fly, swim and run, and range in weight from a couple of grams to hundreds of tonnes.

A wealth of fossil evidence had pointed to the notion that the group, or clade, grew in an “explosion” of species shortly after the dinosaurs’ end about 65 million years ago.

But a range of genetic studies that look for fairly regular changes in genetic makeup suggested that the group arose as long as 100 million years ago, with mammals such as early rodents sharing the Earth with the dinosaurs. (via BBC News - Earliest placental mammal ancestor pinpointed)

Once upon a time there were two girls. One was kind and helpful and was rewarded with a box of gold. The other was mean and lazy and was rewarded with a box of snakes. You may know another version of this fairy tale though, because it changed as it spread across Europe. A new study of how it changed shows that people who came from different language groups – or who lived a few hundred kilometres apart – were more likely to have children with each other than to exchange their version of the story. Analysing folklore in this way, using techniques from genetic analysis, may give us new insights into how cultures evolve.

There are numerous versions of the “kind and unkind girls” tale across Europe. Quentin Atkinson at the University of Auckland, New Zealand, and colleagues took a database of 700 versions collected a century or more ago in 31 languages, and quantified their differences. They then analysed these variations using standard techniques from population genetics, used to determine how common mutant versions of a gene are according to ethnic group or across a region.

“We are the first to include both those variables, so we can tease the effect of linguistic boundaries apart from geography,” says Atkinson. He found that both factors matter. “Two French versions of the tale collected 100 kilometres apart should differ as much as a French and a German version collected 10 kilometres apart,” he says. By the same token however, he found that a French version of the tale from near the German border might be more similar to a German version from just across the border than to another French variant found hundreds of kilometers away. (via Genes mix across borders more easily than folk tales - life - 06 February 2013 - New Scientist)

Music doesn’t go along at a single, mechanical speed. Notes of various lengths mix to create a specific, complex rhythm. New research suggests protein synthesis works the same way. The sequence of events is elegant: proteins are assembled when ribosomes match mRNA sequences up with specific tRNA molecules. Those tRNAs carry specific amino acids that link together in a chain to form a specific protein.

But multiple RNA sequences can encode the same amino acid—some that are translated quickly, and some slowly. Although they all result in proteins with identical composition, the choice of mRNA sequence can dramatically change the rate at which the protein is made.

Research from Stanford University biology Professor Judith Frydman and researcher Sebastian Pechmann now reveals that this protein synthesis “rhythm” may be evolutionarily adjusted to control the folding of the new protein chain as it emerges from the ribosome.

The finding may explain how RNA sequences define the final, folded form of a protein—a fundamental problem in molecular biology, since proteins need to fold in order to function.

“For around 50 years, there has been a conceptual gap between the sequence and the final structure,” says Pechmann, a postdoctoral scholar in the Frydman Lab. “There’s been the sense that there’s much more information in the sequence than can be deciphered at the moment.”