Lifeboat Foundation

Telomeres are large nucleoproteins structures that cap the ends of chromosomes in eukaryotic cells. When a cell divides, a small portion of the telomere is lost due to the inherently incomplete process of genome replication. If left unchecked, over time the telomeres will reach a critically short length and the cell will face genomic instability, deterioration or death. To offset this shortening, an essential enzyme called telomerase rebuilds the telomeres by synthesizing new telomeric DNA repeats at chromosome ends. Kelly Nguyen’s group, in the LMB’s Structural Studies Division, has solved the first complete atomic model of this enzyme and discovered a histone dimer as novel telomerase subunits.

Telomeres act as a barrier to protect the genetic information from progressive degradation arising from incomplete DNA replication. Additionally, telomeres distinguish the natural chromosome ends from DNA double-strand breaks, thereby avoiding an illicit DNA damage response and preventing intrachromosomal fusion. This makes telomeres essential for the preservation of genome and chromosome stability. In previous research, Kelly had discovered the architecture and composition of human telomerase holoenzyme at 8 Å (Ångströms) resolution using cryo-EM. However, to understand the molecular mechanism governing telomerase mediated telomere maintenance, a high-resolution structure of the complex was required.

To conduct this study, Kelly’s group, in collaboration with Kathleen Collins at the University of California, Berkeley, and Rhiju Das at Stanford University, prepared telomerase by extracting it from cultured human cells, before imaging using cryo-EM—resulting in the collection of almost 44000 images. This data was analyzed using RELION—a complex computer program developed at the LMB—in order to achieve the 3.4−3.8 Å structure of telomerase. From this Kelly and members of her group, George Ghanim, Adam Fountain, and Marike van Roon, were able to build the first complete atomic model of telomerase, with 12 protein subunits and telomerase RNA. By completing the structure to such a high resolution, the group was not only able to illuminate how common RNA and protein motifs work together, but also to highlight new interactions.

History has been made!!!

It made 5 grams of the gas — equivalent to what an astronaut at Mars would need to breathe for roughly 10 minutes.

An instrument in the Perseverance rover produces oxygen from the planet’s carbon dioxide atmosphere.

Continue reading “NASA’s rover makes breathable oxygen on Mars” »

The milestone, which the MOXIE instrument achieved by converting carbon dioxide into oxygen, points the way to future human exploration of the Red Planet.

The growing list of “firsts” for Perseverance, NASA ’s newest six-wheeled robot on the Martian surface, includes converting some of the Red Planet’s thin, carbon dioxide-rich atmosphere into oxygen. A toaster-size, experimental instrument aboard Perseverance called the Mars Oxygen In-Situ Resource Utilization Experiment (MOXIE) accomplished the task. The test took place April 20, the 60th Martian day, or sol, since the mission landed on February 18.

While the technology demonstration is just getting started, it could pave the way for science fiction to become science fact – isolating and storing oxygen on Mars to help power rockets that could lift astronauts off the planet’s surface. Such devices also might one day provide breathable air for astronauts themselves. MOXIE is an exploration technology investigation – as is the Mars Environmental Dynamics Analyzer (MEDA) weather station – and is sponsored by NASA’s Space Technology Mission Directorate (STMD) and Human Exploration and Operations Mission Directorate.

The bizarre genome of the world’s most mysterious flowering plants shows how far parasites will go in stealing, deleting and duplicating DNA.

Volcanic eruptions deep in our oceans are capable of extremely powerful releases of energy, at a rate high enough to power the whole of the United States, according to research published today.

Eruptions from deep-sea volcanoes were long-thought to be relatively uninteresting compared with those on land. While terrestrial volcanoes often produce spectacular eruptions, dispersing volcanic ash into the environment, it was thought that deep marine eruptions only produced slow moving lava flows.

But data gathered by remotely operated vehicles deep in the North East Pacific and analyzed by scientists at the University of Leeds, has revealed a link between the way ash is dispersed during submarine eruptions and the creation of large and powerful columns of heated water rising from the ocean floor, known as megaplumes.

The highlight of the new chart is a wake of stars, stirred up by a small galaxy set to collide with the Milky Way. The map could also offer a new test of dark matter theories.

On April 17, 2021, the New Horizons spacecraft passed 50 astronomical units — 50 times Earth’s distance from the sun — while speeding toward interstellar space. It also captured an image of another earthly spacecraft, even farther out.

Oxygen isn’t just the stuff we breathe. Rocket propellant depends on oxygen, and future explorers will depend on producing propellant on Mars to make the trip home.

The instrument, called the Mars Oxygen In-Situ Resource Utilization Experiment (MOXIE), is a technology demonstration that could eventually be scaled up to produce enough propellant to enable a crew of astronauts to take off from the surface of the Red Planet.

“This is a critical first step at converting carbon dioxide to oxygen on Mars,” said Jim Reuter, associate administrator of NASA’s Space Technology Mission Directorate (STMD), in a statement. “MOXIE has more work to do, but the results from this technology demonstration are full of promise as we move toward our goal of one day seeing humans on Mars.”

Continue reading “NASA’s Perseverance Rover Just Turned Martian CO2 Into Oxygen” »

There’s a chance the submarine fell to a depth of over 2000 feet.