Lifeboat Foundation

The posterior parietal cortex (PPC) plays a key role in integrating sensory inputs from different modalities to support adaptive behavior. Neuronal activity in PPC reflects perceptual decision-making across behavioral tasks, but the mechanistic involvement of PPC is unclear. In an audiovisual change detection task, we tested the hypothesis that PPC is required to arbitrate between the noisy inputs from the two different modalities and help decide in which modality a sensory change occurred. In trained male mice, we found extensive single-neuron and population-level encoding of task-relevant visual and auditory stimuli, trial history, as well as upcoming behavioral responses. However, despite these rich neural correlates, which would theoretically be sufficient to solve the task, optogenetic inactivation of PPC did not affect visual or auditory performance. Thus, despite neural correlates faithfully tracking sensory variables and predicting behavioral responses, PPC was not relevant for audiovisual change detection. This functional dissociation questions the role of sensory-and task-related activity in parietal associative circuits during audiovisual change detection. Furthermore, our results highlight the necessity to dissociate functional correlates from mechanistic involvement when exploring the neural basis of perception and behavior.

SIGNIFICANCE STATEMENT The posterior parietal cortex (PPC) is active during many daily tasks, but capturing its function has remained challenging. Specifically, it is proposed to function as an integration hub for multisensory inputs. Here, we tested the hypothesis that, rather than classical cue integration, mouse PPC is involved in the segregation and discrimination of sensory modalities. Surprisingly, although neural activity tracked current and past sensory stimuli and reflected the ongoing decision-making process, optogenetic inactivation did not affect task performance. Thus, we show an apparent redundancy of sensory and task-related activity in mouse PPC. These results narrow down the function of parietal circuits, as well as direct the search for those neural dynamics that causally drive perceptual decision-making.

A “bio-battery” made from genetically engineered bacteria could store excess renewable energy and release it as needed.

A biotechnology company based in Israel wants to replicate a recent experiment that successfully created an artificial mouse embryo from stem cells — only this time with human cells.

Scientists at Weizmann’s Molecular Genetics Department grew “synthetic mouse embryos” in a jar without the use of sperm, eggs, or a womb, according to a paper published in the journal Cell on August 1. It was the first time the process had been successfully completed, Insider’s Marianne Guenot reported.

The replica embryos could not develop into fully-formed mice and were therefore not “real,” Jacob Hanna, who led the experiment, told the Guardian. However, scientists observed the synthetic embryos having a beating heart, blood circulation, the start of a brain, a neural tube, and an intestinal tract.

Cas13 variants with minimal collateral effect are expected to be more competitive for in vivo RNA editing and future therapeutic applications, researchers claim.

Scientists from the Chinese Academy of Sciences (CAS) have allegedly developed a new “controllable, reversible and safer” gene-editing approach using CRISPR technology.

The system, named Cas13D-N2V8, showed a significant reduction in the number of off-target genes and no detectable collateral damage in cell lines and somatic cells, which indicated its future potential, according to a report published in South China Morning Post newspaper on Wednesday.

Continue reading “Chinese scientists develop new ‘reversible’ gene-editing technique” »

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The system, named Cas13D-N2V8, showed a significant reduction in the number of off-target genes and no detectable collateral damage in cell lines and somatic cells, which indicated its future potential, according to a report published in South China Morning Post newspaper on Wednesday.

Researchers have succeeded in making photosynthesis more efficient in soybean plants, in a major breakthrough that will mean less forest has to be cut down to make way for farms.

In the 1980s, biologist Dr Michael Rose started to selectively breed Drosophila fruit flies for increased longevity. Today, the descendants of the original Methuselah flies are held by biotech firm Genescient Corporation and live 4.5 times longer than normal fruit flies.

The flies’ increased lifespan is explained by a significant number of systemic genetic changes — but how many of these variations represent lessons that can be used to design longevity therapies for humans? Dr. Ben Goertzel and his bio-AI colleagues at SingularityNET and Rejuve. AI are betting the answer is quite a few.

SingularityNET and Rejuve. AI have launched a partnership with Genescient to apply advanced machine learning and machine reasoning methods to transfer insights gained from the Methuselah fly genome to the human genome. The goal is to acquire new information regarding gene therapies, drugs or nutraceutical regimens for prolonging healthy human life.

Damage to the ends of your chromosomes can create “zombie cells” that are still alive but can’t function, according to our recently published study in Nature Structural and Molecular Biology.

When cells prepare to divide, their DNA is tightly wound around proteins to form chromosomes that provide structure and support for genetic material. At the ends of these chromosomes are repetitive stretches of DNA called telomeres that form a protective cap to prevent damage to the genetic material.

However, telomeres shorten each time a cell divides. This means that as cells divide more and more as you age, your telomeres become increasingly shorter and more likely to lose their ability to protect your DNA.

Is de-extinction realistic?

Scientists in the US and Australia have announced a multi-million dollar project — resurrecting the extinct Tasmanian tiger. The last known marsupial officially called a thylacine, died in the 1930s. According to the team, the extinct thylacine can be recreated using stem cells and gene-editing technology, and the first one could be “reintroduced” to the wild within 10 years.

We would strongly advocate that first and foremost we need to protect our biodiversity from further extinctions, but unfortunately we are not seeing a slowing down in species loss.

Continue reading “‘Jurassic Park’? Scientists want to resurrect Australia’s Tasmanian tiger” »