Like any law-abiding train passenger, a molecule called oskar RNA carries a stamped ticket detailing its destination and form of transport, scientists at the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany, have found.
Oskar RNA (red) is transported to the posterior pole in a normal fruit fly egg cell (left), but not in an oocyte with a mutated SOLE tag (right).
They show that for this molecule, moving in the right direction isn't enough: speed is of the essence. Their study, published online today in Nature Structural & Molecular Biology, also provides clues as to how a single molecule could receive tickets for different destinations, depending on what type of cell it is in.
For a fruit fly embryo to develop properly, oskar RNA produced by the mother has to enter the egg cell, or oocyte, as it matures, and be taken to one of its ends – the posterior pole. Researchers in Anne Ephrussi's group at EMBL have now found that this movement is more complicated than it seemed. When oskar is processed for transport by a mechanism called splicing, two different tags – SOLE and EJC – are attached to it, next to each other, at a specific spot.
Ephrussi and colleagues found that both tags have to be in place for oskar to reach the right destination. Together, they seem to form a ticket that marks oskar for transport to the posterior pole, differentiating it from the many other RNAs that enter the oocyte bound for different destinations.
When they genetically altered the SOLE tag, the scientists found that oskar didn't go to the oocyte's posterior pole, as it should. But surprisingly, it did still move, and seemingly in the right direction. The problem, the researchers realised, was that oskar is racing towards a moving target.
As the oocyte grows, it becomes longer, in effect taking the posterior pole further and further away as oskar is carried towards it. With a defective SOLE tag, oskar seemed unable to move fast enough to overcome the oocyte's growth. So somehow this 'ticket' affects the speed of transport, too.
Ephrussi and colleagues are now investigating how SOLE and EJC interact with each other, and how they might influence the cellular machinery that transports oskar. The scientists would also like to explore an interesting possibility raised by their current findings. They discovered that the SOLE tag is only formed if the RNA molecule is spliced.
Since some RNAs can be spliced at different spots along their length, this means the same RNA could potentially be issued with tickets for different destinations – for instance, in different cell types – depending on which parts of it are spliced.
Sonia Furtado Neves | EurekAlert!
The birth of a new protein
20.10.2017 | University of Arizona
Building New Moss Factories
20.10.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau
University of Maryland researchers contribute to historic detection of gravitational waves and light created by event
On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...
Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.
Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....
Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).
When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...
Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.
How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...
Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.
It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...
17.10.2017 | Event News
10.10.2017 | Event News
10.10.2017 | Event News
20.10.2017 | Information Technology
20.10.2017 | Materials Sciences
20.10.2017 | Interdisciplinary Research