The envelope acts as a barrier between the outer cell compartment, called the cytoplasm, and DNA stored in the cell nucleus. It regulates which molecules are allowed to pass back and forth between the two compartments. Most of this traffic passes through basket-shaped passageways called nuclear pores, which consist of intricately-woven proteins. “We haven't yet identified all the molecules in the nuclear envelope, and many questions remain about the process by which molecules are granted or denied passage,” says Peter Askjaer of IRB.
The new study shows that a protein called MEL-28 is a component of nuclear pores in the worm C. elegans, one of biology's most important model organisms. More importantly, it reveals that MEL-28 is one of the key architects as bits of membrane and proteins are drawn together to build new envelopes.
When scientists blocked the activity of MEL-28, they discovered that patches of membranes attached themselves to DNA but couldn't seal themselves off into a complete envelope. A step-by-step analysis showed that without the protein, other molecules are not drawn together properly as envelopes are rebuilt. The components were scrambled; pores were no longer built, and the wrong molecules were able to get access to DNA. Because MEL-28 remains attached to DNA during the entire process of cell division, the scientists believe it plays a crucial role early in the formation of the envelope.
MEL-28 has a close relative in human cells; one of the researchers’ future projects will be to examine whether this molecule plays a similar role in our own species. Oddly-shaped nuclear envelopes are seen in human genetic diseases such as progeria, a rare condition that causes affected children to age prematurely, and some types of muscular dystrophies. “Understanding how the nuclear envelope forms in the first place may eventually help us understand how changes in it can cause these diseases and potentially how they can be treated,” says Askjaer.
Sarah Sherwood | alfa
Enduring cold temperatures alters fat cell epigenetics
19.04.2018 | University of Tokyo
Full of hot air and proud of it
18.04.2018 | University of Pittsburgh
Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.
Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...
Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.
The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...
Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.
Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...
In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...
In an article that appears in the journal “Review of Modern Physics”, researchers at the Laboratory for Attosecond Physics (LAP) assess the current state of the field of ultrafast physics and consider its implications for future technologies.
Physicists can now control light in both time and space with hitherto unimagined precision. This is particularly true for the ability to generate ultrashort...
13.04.2018 | Event News
12.04.2018 | Event News
09.04.2018 | Event News
19.04.2018 | Materials Sciences
19.04.2018 | Physics and Astronomy
19.04.2018 | Physics and Astronomy