Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: genetics – Page 271

Optogenetics reveals new insights into circuits of the brain

To date, scientists have largely been in the dark with regard to how individual circuits operate in the highly branched networks of the brain. Mapping these networks is a complicated process, requiring precise measurement methods. For the first time, scientists from the Max Planck Institute for Biological Cybernetics in Tübingen, Germany, together with researchers from the Ernst Strüngmann Institute in Frankfurt and Newcastle University in England, have now functionally proven a so far poorly understood neural connection in the visual system of monkeys using optogenetic methods. To this end, individual neurons were genetically modified so that they became sensitive to a light stimulus.

For decades microstimulation was the method of choice for activating neurons – the method proved to be reliable and accurate. That is why it is also used medically for deep stimulation. The Tübingen-based scientists were now able to show that optogenetics, a biological technique still in its infancy, delivers comparable results.

With optogenetics it is possible to directly influence the activity of neurons by light. To do this are genetically modified with the help of viruses to express light-sensitive ion channels in their cell membrane. Through blue light pulses delivered directly into the brain, the modified neurons can then be systematically activated.

Epileptic seizures and depression may share a common genetic cause, study suggests

From the time of Hippocrates, physicians have suspected a link between epilepsy and depression. Now, for the first time, scientists at Rutgers University-New Brunswick and Columbia University have found evidence that seizures and mood disorders such as depression may share the same genetic cause in some people with epilepsy, which may lead to better screening and treatment to improve patients’ quality of life.

The scientists studied dozens of unusual families with multiple relatives who had epilepsy, and compared the family members’ of with that of the U.S. population.

They found an increased incidence of mood disorders in persons who suffer from a type of the condition called focal epilepsy, in which begin in just one part of the brain. But mood disorders were not increased in people with generalized epilepsy, in which seizures start on both sides of the brain.

A DNA “Oracle” for Predicting the Future Evolution of Gene Regulation

Researchers created a mathematical framework to examine the genome and detect signatures of natural selection, deciphering the evolutionary past and future of non-coding DNA.

Despite the sheer number of genes that each human cell contains, these so-called “coding” DNA sequences comprise just 1% of our entire genome. The remaining 99% is made up of “non-coding” DNA — which, unlike coding DNA, does not carry the instructions to build proteins.

One vital function of this non-coding DNA, also called “regulatory” DNA, is to help turn genes on and off, controlling how much (if any) of a protein is made. Over time, as cells replicate their DNA to grow and divide, mutations often crop up in these non-coding regions — sometimes tweaking their function and changing the way they control gene expression. Many of these mutations are trivial, and some are even beneficial. Occasionally, though, they can be associated with increased risk of common diseases, such as type 2 diabetes, or more life-threatening ones, including cancer.

A speed limit could be a breakthrough for stem cell therapy

A totipotent cell is a single cell that can give rise to a new organism, if given appropriate maternal support. Totipotent cells have many properties, but we do not know all of them yet. Researchers at Helmholtz Munich have now made a new discovery.

“We found out that in totipotent , the mother cells of stem cells, DNA replication occurs at a different pace compared to other more differentiated cells. It is much slower than in any other cell type we studied,” says Tsunetoshi Nakatani, first-author of the new study.

DNA replication, in fact, is one of the most important biological processes. Throughout the course of our lives, each time that a cell divides it generates an exact copy of its DNA so that the resulting daughter cells carry identical genetic material. This fundamental principle enables faithful inheritance of our genetic material.

CRISPR On-Off Switch Will Help Unlock the Secrets of Our Immune System

Can we turn up—or dial down—their fervor by tweaking their genes?

Enter a new kind of CRISPR. Known mostly as a multi-tool to cut, snip, edit, or otherwise kneecap an existing gene, this version—dubbed CRISPRa—forcibly turns genes on. Optimized by scientists at Gladstone Institutes and UC San Francisco, the tool is counterbalanced by CRISPRi—“i” for “interference,” which, you guessed it, interferes with the gene’s expression.

Though previously used in immortal cells grown in labs, this is the first time these CRISPR tools are rejiggered for cells extracted from our bodies. Together, the tools simultaneously screened nearly 20,000 genes in T cells isolated from humans, building a massive genetic translator—from genes to function—that maps how individual genes influence T cells.

Anti-aging molecules safely reset mouse cells to youthful states

One of the especially promising therapies to appear in the realm of anti-aging research involves a set of molecules known as Yamanaka factors, which scientists have deployed to rejuvenate aging cells, trigger muscle regeneration and tackle glaucoma. New research at the Salk Institute has sought to build on these short-term and specific use cases by demonstrating how these molecules can reverse signs of aging in middle-aged and elderly mice, with no evidence of health problems following the extended treatment.

The Yamanaka factors at the center of this study are a set of four reprogramming molecules that can reset the molecular clock found in the cells of the body. They do so by returning unique patterns of chemicals known as epigenetic markers, which evolve through aging, to their original states.

This approach has been used to convert adult cells back into stem cells, that can then differentiate into different cell types. The Salk Institute team has previously used the approach to reverse signs of aging in mice with a premature aging disease, and improve the function of tissues found in the heart and brain. Separately, Stanford University scientists last year used the technique to give elderly mice the muscle strength of younger mice.

Science competitions can help to catapult your science into the real world

The XPrize and other competitions are helping to advance science and technological innovation.

Over the years, we have had alumni go on to become successful academic scientists, company managers and entrepreneurs. The networks that the participants create with each other during the competition are useful to tap into throughout their careers. Recently, I also learnt that a winning team from 2020 decided to create a bioelectronics start-up, INIA Biosciences, that aims to use ultrasound to interact with the immune system to relieve chronic inflammatory diseases.

More companies and foundations are seeing the advantages of science competitions and are organizing innovation challenges. The organizers benefit from recruiting talented people, gaining fresh ideas and promoting an image of innovativeness. The participants are rewarded with training, network building and prize money. In addition to the Innovation Cup, we also organize events such as the €1 million Future Insight Prize, which is given out annually to honour and enable scientists solving key challenges of humanity.

MARJOLEIN CROOIJMANS: The judge

Chair of the International Genetically Engineered Machine (iGEM) Entrepreneurship Program Innovation Community (EPIC), Cambridge, Massachusetts and PhD Student at Leiden University, Leiden, Netherlands.

Single test for over 50 genetic diseases will cut diagnosis from decades to days

Further research shows that the test is accurate.

When it comes to genetic neurological and neuromuscular diseases, screening early is key to getting the right treatment. A new DNA test developed by researchers at the Garvan Institute of Medical Research in Sydney may help in this process, as reported by the institution in a press release published on Saturday.

Garvan researchers have shown how new genomic sequencing technology can reduce the ‘diagnostic odyssey’ experienced by people with rare neurological and neuromuscular diseases.

Protein tweak makes CRISPR gene editing 4,000 times less error-prone

The CRISPR gene-editing system is a powerful tool that could revolutionize medicine and other sciences, but unfortunately it has a tendency to make edits to the wrong sections of DNA. Now, researchers at the University of Texas at Austin have identified a previously unknown structure of the protein that drives these mistakes, and tweaked it to reduce the likelihood of off-target mutations by 4,000 times.

CRISPR tools use certain proteins, most often Cas9, to make precise edits to specific DNA sequences in living cells. This can involve cutting out problematic genes, such as those that cause disease, and/or slotting in beneficial ones. The problem is that sometimes the tool can make changes to the wrong parts, potentially triggering a range of other health issues.

And in the new study, the UT researchers discovered how some of these errors can happen. Usually, the Cas9 protein is hunting for a specific sequence of 20 letters in the DNA code, but if it finds one where 18 out of 20 match its target, it might make its edit anyway. To find out why this occurs, the team used cryo-electron microscopy to observe what Cas9 is doing when it interacts with a mismatched sequence.