Lifeboat Foundation

Viruses in soil may not be as destructive to bacteria as once thought and could instead act like lawnmowers, culling older cells and giving space for new growth, according to research out of the University of California, Davis, published Sept. 28 in the journal Nature Ecology and Evolution.

How viruses affect ecosystems, including bacteria, is challenging to untangle because they are complex and change over time and space. But the first annual rain on Mediterranean ecosystems, such as those in California, offers a kind of reset, triggering activity that can be observed.

Scientists took soil from four California grasslands, brought it back to their lab and simulated precipitation by watering the dry samples, which grew microorganisms and viruses. They tracked changes over 10 days.

The effect of a TE on its host can be classified analogous to the effect of point mutations. In the majority of cases, the consequences of a TE their activity (transposition to a new genomic site) is either neutral or deleterious. The latter occurs, when TEs disrupt genes and their functions, or when, they trigger de-novo genomic instability by transposition or TE-mediated chromosomal rearrangements, which can lead to disease^{1, 3}. TEs can occasionally have a positive impact on the host genome, for example, by impacting gene regulatory networks. In the British peppered moth (Biston betularia), a TE inserted within the first intron of the cortex gene, resulted in increased transcription levels, subsequently affecting cell cycle regulation during wing-disc development through the amount of cortex protein product, resulting in the iconic melanic form⁴. However, more research is needed to understand these different evolutionary impacts that TEs can have when interacting with their host genome.

The increased accessibility to high throughput sequencing technologies has greatly increased our ability to analyse genetic differences caused by changes at the nucleotide level, and patterns of natural selection on coding sequences, and simultaneously allowed us to disentangle phenotypic differences at the nucleotide level. Mounting evidence has started to shed light on non-coding regions having important effects on genomic variation³. While TEs can be found in the genomes of virtually all organisms, large proportions of TEs are often absent from reference genomes, as their repetitive nature impedes their assembly and can result in collapsed regions within the reference genome^{2, 5}. These difficulties have led to an increased demand for reference genomes that are of a higher quality and are more complete. More importantly, a new demand for high-quality annotations of non-coding regions in reference genomes has surfaced. Annotations of non-coding regions are imperative to study the evolution of these regions between and within species. Improvements in sequencing techniques, especially the addition of long-read sequencing, and improved bioinformatic analytical tools are resulting in the assembly of increasingly gapless reference genomes, enabling the curation of high-quality TE annotations.

The current efforts of large consortia, such as the VGP⁶ and the B10K⁷ to create high-quality references for a wide variety of organisms provide invaluable data to improve our endeavours for a better understanding of TEs. With these new resources we can take our research into TEs and their effects on host genomes further, for example, to better understand the evolution of complex traits across phylogenomic scales. One such a complex trait is seasonal bird migration and recent research across a migratory divide in willow warblers identified a diagnostic TE correlated with migratory direction⁸. Here we focus on the Eurasian blackcap (Sylvia atricapilla), another iconic model species for bird migration, and consequently, the resource published here may be able to add insight to the quest to resolve the genetic background of migratory behaviour.

Ribonucleic acid (RNA) is a molecule which is present in cells and made of genetic material to help build proteins necessary for cell function. RNA provides a template for the construction of proteins and is essential for cell and organism life. Immune cells rely on these proteins, including CD8⁺ or cytotoxic T cells which are responsible for killing invading pathogens. Importantly, cytotoxic T cells are a major component of the memory immune response. A pool of T cells specifically designed to recognize an invader is stored for future invasion of that particular pathogen. For example, once these cells are exposed to an invading antigen or protein, the immune system will expand T cells specific to that antigen and remember the antigen next time it enters the body. Vaccines work in a similar way by introducing a foreign antigen to the body, so the immune system is ready if the pathogen ever enters your body in the future. Only a small set of T cells that expand survive and it is unclear how this process occurs.

Recently a team of researchers at the University of Massachusetts Amherst (UMass) demonstrated that a single strand of RNA governs a T cells ability to recognize and kill tumors. The single strand of RNA is known as let-7 and is a microRNA, which is responsible for gene expression regulation. The recent discovery may improve vaccine development and cellular memory to enhance immunotherapy against cancers. Immunotherapy is a general term referring to cancer therapies that try to activate the immune system to kill the tumor compared to other drugs that try to directly kill the tumor with chemicals, such as chemotherapy.

The report published in Nature Communications identified that the microRNA, let-7, may enhance memory of T cells. Researchers led by Dr. Leonid Pobezinsky, Associate Professor of Veterinary and Animal Sciences at UMass, further built on our understanding of how T cells form immune memory. Pobezinsky and colleagues found that a small piece of microRNA that has been present throughout evolution is expressed in memory cells. Additionally, they found that more let-7 a cell has, the more likely that cell will recognize a cancer cell and kill it. The increased let-7 also indicates that the cell will turn into a memory cell after being exposed to an antigen. The regulation of enhanced memory T cells by let-7 is an integral process key to fight infections. This is a critical finding, especially because memory cells retain stem-like characteristics and can survive for decades.

Now, scientists have a mathematical model that closely matches how the human brain processes visual information.

Scientists have confirmed that human brains are naturally wired to perform advanced calculations, much like a high-powered computer, to make sense of the world through a process known as Bayesian inference.

In a study published in the journal Nature Communications, researchers from the University of Sydney, University of Queensland and University of Cambridge developed a specific mathematical model that closely matches how human brains work when it comes to reading vision. The model contained everything needed to carry out Bayesian inference.

Humanity is about to suffer.

In an age of unpredictable job evolution, it is hard to argue that the knowledge acquisition historically associated with a university degree is still relevant. But as university qualifications become more commonplace, recruiters and employers will increasingly demand them, regardless of whether they are actually required for a specific job. Research shows that the correlation between education level and job performance is weak, and that intelligence scores are a much better indicator of job potential. If we were to pick between a candidate with a college degree and a candidate with a higher intelligence score, we could expect the latter to outperform the former in most jobs, particularly when those jobs require constant thinking and learning.

The measurement of the mysterious form of matter around these quasar galaxies could have profound implications for our understanding of how the cosmos has evolved.

Insights into healing and aging were discovered by National Institutes of Health researchers and their collaborators, who studied how a tiny sea creature regenerates an entire new body from only its mouth. The researchers sequenced RNA from Hydractinia symbiolongicarpus, a small, tube-shaped animal that lives on the shells of hermit crabs. Just as the Hydractinia were beginning to regenerate new bodies, the researchers detected a molecular signature associated with the biological process of aging, also known as senescence. According to the study published in Cell Reports, Hydractinia demonstrates that the fundamental biological processes of healing and aging are intertwined, providing new perspective on how aging evolved.

https://www.nih.gov/news-events/news-releases/scientists-dis…a-creature

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Professor Geoff Duller from Aberystwyth University explained that, given the considerable age of these artifacts, assigning precise dates to them presented a significant challenge. To address this issue, luminescence dating techniques were employed. These innovative dating methods have broad-ranging implications, enabling the dating of much older materials and facilitating the reconstruction of sites that offer insights into human evolution—in the case of Kalambo Falls, an excavation conducted in the 1960s yielded comparable wooden fragments. Still, their dating had remained elusive, leaving the true importance of the site uncertain until now.

Kalambo Falls is located on the Kalambo River above a 772-foot (235-meter) waterfall on the border of Zambia and Tanzania near Lake Tanganyika. The area is on a ‘tentative ‘list from UNESCO for becoming a World Heritage site because of its archaeological significance.