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A group of scientists at Northeastern University are making progress using nanotechnology to prevent, diagnose and fight the coronavirus.

Thomas Webster, professor of chemical engineering at Northeastern University, has been working with nanotechnology for decades. Now, he and his team are finding new applications with the coronavirus.

Experts say that COVID-19 almost certainly arose naturally, rather than being bioengineered.

But that doesn’t mean the next pandemic won’t involve a deadly virus designed by an adversary, as distinguished fellow at Harvard Law Vivek Wadhwa argues in a new essay for Foreign Policy.

“It is now too late to stop the global spread of these technologies — the genie is out of the bottle,” he wrote. “We must treat the coronavirus pandemic as a full dress rehearsal of what is to come — unfortunately, that includes not only viruses that erupt from nature, but also those that will be deliberately engineered by humans.”

Controlling brains with light.


Thanks to optogenetics, in just ten years we’ve been able to artificially incept memories in mice, decipher brain signals that lead to pain, untangle the neural code for addiction, reverse depression, restore rudimentary sight in blinded mice, and overwrite terrible memories with happy ones. Optogenetics is akin to a universal programming language for the brain.

But it’s got two serious downfalls: it requires gene therapy, and it needs brain surgery to implant optical fibers into the brain.

This week, the original mind behind optogenetics is back with an update that cuts the cord. Dr. Karl Deisseroth’s team at Stanford University, in collaboration with the University of Minnesota, unveiled an upgraded version of optogenetics that controls behavior without the need for surgery. Rather, the system shines light through the skulls of mice, and it penetrates deep into the brain. With light pulses, the team was able to change how likely a mouse was to have seizures, or reprogram its brain so it preferred social company.

Summary: A clusterization approach allows researchers to analyze dendritic spines in new ways.

Source: SPbPU

Dendritic spines are small protrusions from a neuron’s dendrite membrane, where contact with neighboring axons is formed to receive synaptic input. These spines have different sizes, shapes, and density. Changes in the characteristics of the dendritic spines are associated with learning and memory and could be a feature of neurodegenerative disorders like Alzheimer’s disease and Huntington’s disease.

Chemical space contains every possible chemical compound. It includes every drug and material we know and every one we’ll find in the future. It’s practically infinite and can be frustratingly complex. That’s why some chemists are turning to artificial intelligence: AI can explore chemical space faster than humans, and it might be able to find molecules that would elude even expert scientists. But as researchers work to build and refine these AI tools, many questions still remain about how AI can best help search chemical space and when AI will be able to assist the wider chemistry community.

Outer space isn’t the only frontier curious humans are investigating. Chemical space is the conceptual territory inhabited by all possible compounds. It’s where scientists have found every known medicine and material, and it’s where we’ll find the next treatment for cancer and the next light-absorbing substance for solar cells.

But searching chemical space is far from trivial. For one thing, it might as well be infinite. An upper estimate says it contains 10180 compounds, more than twice the magnitude of the number of atoms in the universe. To put that figure in context, the CAS database—one of the world’s largest—currently contains about 108 known organic and inorganic substances, and scientists have synthesized only a fraction of those in the lab. (CAS is a division of the American Chemical Society, which publishes C&EN.) So we’ve barely seen past our own front doorstep into chemical space.

However, it was unclear how TERRA got to the tip of chromosomes and remained there. “The telomere makes up only a tiny bit of the total chromosomal DNA, so the question is ‘how does this RNA find its home?’” Lingner says. To address this question, postdoc Marianna Feretzaki and others in the teams of Joachim Lingner at EPFL and Lumir Krejci at Masaryk University set out to analyze the mechanism through which TERRA accumulates at telomeres, as well as the proteins involved in this process. The findings are published in * Nature*.

**Finding home**

By visualizing TERRA molecules under a microscope, the researchers found that a short stretch of the RNA is crucial to bring it to telomeres. Further experiments showed that once TERRA reaches the tip of chromosomes, several proteins regulate its association with telomeres. Among these proteins, one called RAD51 plays a particularly important role, Lingner says.

RAD51 is a well-known enzyme that is involved in the repair of broken DNA molecules. The protein also seems to help TERRA stick to telomeric DNA to form a so-called “RNA-DNA hybrid molecule”. Scientists thought this type of reaction, which leads to the formation of a three-stranded nucleic acid structure, mainly happened during DNA repair. The new study shows that it can also happen at chromosome ends when TERRA binds to telomeres. “This is paradigm-shifting,” Lingner says.

The researchers also found that short telomeres recruit TERRA much more efficiently than long telomeres. Although the mechanism behind this phenomenon is unclear, the researchers hypothesize that when telomeres get too short, either due to DNA damage or because the cell has divided too many times, they recruit TERRA molecules. This recruitment is mediated by RAD51, which also promotes the elongation and repair of telomeres. “TERRA and RAD51 help to prevent accidental loss or shortening of telomeres,” Lingner says. “That’s an important function.””

Researchers know how to make precise genetic changes within the genomes of crops, but the transformed cells often refuse to grow into plants. One team has devised a new solution.


Scientists who want to improve crops face a dilemma: it can be difficult to grow plants from cells after you’ve tweaked their genomes.

A new tool helps ease this process by coaxing the transformed cells, including those modified with the gene-editing system CRISPR-Cas9, to regenerate new plants. Howard Hughes Medical Institute Research Specialist Juan M. Debernardi and Investigator Jorge Dubcovsky, together with David Tricoli at the University of California, Davis Plant Transformation Facility, Javier Palatnik from Argentina, and colleagues at the John Innes Centre, collaborated on the work. The team reports the technology, developed in wheat and tested in other crops, October 12, 2020, in the journal Nature Biotechnology.

“The problem is that transforming a plant is still an art,” Dubcovsky says. The success rate is often low – depending on the crop being modified, 100 attempts may yield only a handful of green shoots that can turn into full-grown plants. The rest fail to produce new plants and die. Now, however, “we have reduced this barrier,” says Dubcovsky, a plant geneticist at UC Davis. Using two genes that already control development in many plants, his team dramatically increased the formation of shoots in modified wheat, rice, citrus, and other crops.