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!
Atomic-level motion may drive bacteria's ability to evade immune system defenses
24.04.2017 | Indiana University
Two-dimensional melting of hard spheres experimentally unravelled after 60 years
24.04.2017 | University of Oxford
More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.
Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...
Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.
"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...
The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.
Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...
The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...
Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.
Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...
20.04.2017 | Event News
18.04.2017 | Event News
03.04.2017 | Event News
24.04.2017 | Physics and Astronomy
24.04.2017 | Materials Sciences
24.04.2017 | Life Sciences