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Comment by Dr. Krishna Kumari Challa on April 12, 2023 at 9:47am

Evidence found of possible interdomain horizontal gene transfer leading to development of the eye in vertebrates

A group of molecular and chemical biologists,  has found possible evidence of interdomain horizontal gene transfer leading to the development of the eye in vertebrates. In their study, reported in Proceedings of the National Academy of Sciences researchers used the IQ-TREE software program to trace the evolutionary history of genes associated with vision.

Ever since scientists proved that humans, along with other animals, developed due to evolutionary processes, one problem has stood out—how could evolution possibly account for the development of something as complicated as the eyeball? Even Charles Darwin was said to be stumped by the question. In recent times, this seeming conundrum has been used by some groups as a means to discredit evolutionary theory altogether. In this new effort, researchers sought to answer the question once and for all.

Their work began with the idea that vision in vertebrates may have got its start by using light-sensitive genes transferred from microbes. To find out if that might be the case, the team submitted likely human gene candidates to the IQ-TREE program to look for similar genetic sequences in other creatures, most specifically, microbes.

They found a promising candidate, a gene called IRBP. In humans, it encodes for a protein that is used in the eye as part of a process that converts light into electrical pulses that are eventually sent to the brain via the optic nerve. The research team notes that the gene is an essential component of vision in all vertebrates. IRBP is also found in microbes, most specifically in bacterial peptidases, a class of enzymes that is known for recycling proteins.

The researchers note that while IRBP and the protein that it encodes exists in all vertebrates, it does not exist in most invertebrates. This, they suggest, indicates that the IRBP gene may have been transferred from a microbe over 500 million years ago to an ancient vertebrate, leading to the development of light sensitivity, and over time, to organs such as eyeballs.

More information: Chinmay A. Kalluraya et al, Bacterial origin of a key innovation in the evolution of the vertebrate eye, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2214815120

Comment by Dr. Krishna Kumari Challa on April 12, 2023 at 9:26am

 Link between youthful gut microbiota and potential centenarians

With a growing body of scientific evidence illustrating the influence of gut microbiota on human health, researchers investigated the microflora inhabiting the guts of the world's healthiest people—centenarians.

In the paper, "Longevity of centenarians is reflected by the gut microbiome with youth-associated signatures," published in Nature Aging, the researchers studied the microbiomes of 1,575 individuals aged 20 up to 117, with 297 of them reported to be 100 years old or older. A Research Briefing on the study, titled "Youth-associated signatures in the gut microbiome of centenarians," has been published in the same journal issue.

Participants were evaluated in five age-related groups. Young adults (n = 314, 20–44 years), a middle-aged group (n = 277, 45–65 years), old adults (n = 386, 66–85 years), a nonagenarian group (n = 301, 90–99 years), and a centenarian cohort (n = 297, 100–117 years).

The researchers discovered that the gut microbiome signature in centenarians resembles that of young adults with an overrepresentation of Bacteroides spp., an increase in species evenness (species have a similar abundance), an enrichment of potentially beneficial species from the Bacteroidetes phylum and depletion of potential pathobionts (harmless but can become pathogenic under certain circumstances).

A smaller group of 45 centenarians was tested twice over a year and a half. Results from the group indicated that as centenarians age, the signature species evenness and low pathobionts continued to develop and were enhanced or conserved.

The researchers propose that this microbiome signature is associated with longevity, as they observed in their study, and state that this may counteract the senescence or chronic diseases that generally accompany aging, which this study could not have observed.

The researchers are currently isolating thousands of bacteria strains from the centenarians and testing their benefits on animal models in search of microorganisms that are able to extend the human lifespan. 

Shifu Pang et al, Longevity of centenarians is reflected by the gut microbiome with youth-associated signatures, Nature Aging (2023). DOI: 10.1038/s43587-023-00389-y

Youth-associated signatures in the gut microbiome of centenarians, Nature Aging (2023). DOI: 10.1038/s43587-023-00395-0

Comment by Dr. Krishna Kumari Challa on April 11, 2023 at 1:06pm

India's tiger population rises above 3,000

India's wild tiger population—by far the largest in the world—has risen above 3,000, according to a census released Sunday, boosting efforts to conserve the endangered species.

The largest of all cats, tigers once roamed throughout central, eastern and southern Asia.

But in the past 100 years the tiger has lost more than 93 percent of its historic range and now only survives in scattered populations in 13 countries, according to the International Union for Conservation of Nature (IUCN).

The Indian census estimated there were 3,167 tigers in the wild across the country, up from 2,967 reported in the last such exercise.

Surveys are conducted every four years, using camera traps and computer programmes to individually identify each creature.

The rate of increase has slowed to less than seven percent over the period, down from more than 30 percent in the previous four years.

Deforestation, poaching and human encroachment on habitats have devastated tiger populations across Asia .

India is now home to 75 percent of the global tiger population and also the "largest tiger range country in the world".

In 1900, more than 100,000 tigers were estimated to roam the planet. But that fell to a record low of 3,200 in 2010.

That year, India and 12 other countries with tiger populations signed an agreement to double their big cat numbers by 2022.

India is believed to have had a tiger population of around 40,000 at the time of independence from Britain in 1947.

That fell over subsequent decades to about 3,700 in 2002 and an all-time low of 1,411 four years later, but numbers have since risen steadily.

On the other hand it also tells us that each of us now need to work harder to restore degraded habitats, ensure safe movement of tigers through corridors and promote coexistence.

Source: News agencies

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Comment by Dr. Krishna Kumari Challa on April 11, 2023 at 1:02pm

Luna moths found to use their tails solely for bat evasion In a pair of complementary studies, researchers took a close look at Luna moth (Actias luna) tails through the eyes of birds and female moths to test the tails' role in predation and sexual selection. Scientists have known for about a decade that Luna moths—and other related silkmoths—use their long, trailing tails to misdirect bat attacks.

Light pollution may extend mosquitoes' biting season A new study's finding that urban light pollution may disrupt the winter dormancy period for mosquitoes that transmit West Nile virus could be considered both good news and bad news.

Comment by Dr. Krishna Kumari Challa on April 11, 2023 at 12:58pm

The industry is awash with AI, from cameras to software like Photoshop.

This automation is increasingly blurring boundaries between a photograph and a piece of artwork.

The nature of AI is different to previous innovations, .

because the technology can learn and bring new elements beyond those recorded by film or sensor.

This brings opportunities but also "fundamental challenges around redefining what photography is, and how 'real' a photograph is.

What professional photographers are most concerned about, though, is the rise of AI tools that generate completely new images.

Source: 2023 AFP

https://techxplore.com/news/2023-04-camera-ai-told.html?utm_source=...

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Part 2

Comment by Dr. Krishna Kumari Challa on April 11, 2023 at 12:56pm

Cameras never lie. Really?

Ask AI, They do! 

The camera never lied... until AI told it to

An amateur photographer who goes by the name "ibreakphotos" decided to do an experiment on his Samsung phone last month to find out how a feature called "space zoom" actually works.

The feature, first released in 2020, claims a 100x zoom rate, and Samsung used sparkling clear images of the Moon in its marketing.

Ibreakphotos took his own pictures of the Moon—blurry and without detail—and watched as his phone added craters and other details.

The phone's artificial intelligence software was using data from its "training" on many other pictures of the Moon to add detail where there was none.

"The Moon pictures from Samsung are fake," he wrote, leading many to wonder whether the shots people take are really theirs anymore—or if they can even be described as photographs.

Samsung has defended the technology, saying it does not "overlay" images, and pointed out that users can switch off the function.

The firm is not alone in the race to pack its smartphone cameras with AI—Google's Pixel devices and Apple's iPhone have been marketing such features since 2016.

The AI can do all the things photographers used to labor over—tweaking the lighting, blurring backgrounds, sharpening eyes—without the user ever knowing.

But it can also transform backgrounds or simply wipe away people from the image entirely.

And the debate over AI is not limited to hobbyists on message boards—professional bodies are raising the alarm too.

Part 1

Comment by Dr. Krishna Kumari Challa on April 11, 2023 at 12:37pm

Graviton to photon conversion via parametric resonance: Physicists discover that gravity can create light

Researchers have discovered that in the exotic conditions of the early universe, waves of gravity may have shaken space-time so hard that they spontaneously created radiation.

The physical concept of resonance surrounds us in everyday life. When you're sitting on a swing and want to go higher, you naturally start pumping your legs back and forth. You very quickly find the exact right rhythm to make the swing go higher. If you go off rhythm then the swing stops going higher. This particular kind of phenomenon is known in physics as a parametric resonance.

Your legs act as an external pumping mechanism. When they match the resonant frequency of the system, in this case your body sitting on a swing, they are able to transfer energy to the system making the swing go higher.

These kinds of resonances happen all over the place, and a team of researchers have discovered that an exotic form of parametric resonance may have even occurred in the extremely early universe. 

Perhaps the most dramatic event to occur in the entire history of the universe was inflation. This is a hypothetical event that took place when our universe was less than a second old. During inflation our cosmos swelled to dramatic proportions, becoming many orders of magnitude larger than it was before. The end of inflation was a very messy business, as gravitational waves sloshed back and forth throughout the cosmos.

Normally gravitational waves are exceedingly weak. We have to build detectors that are capable of measuring distances less than the width of an atomic nucleus to find gravitational waves passing through the Earth. But researchers have pointed out that in the extremely early universe these gravitational waves may have become very strong.

And they may have even created standing wave patterns where the gravitational waves weren't traveling but the waves stood still, almost frozen in place throughout the cosmos. Since gravitational waves are literally waves of gravity, the places where the waves are the strongest represent an exceptional amount of gravitational energy.

The researchers found that this could have major consequences for the electromagnetic field existing in the early universe at that time. The regions of intense gravity may have excited the electro magnetic field enough to release some of its energy in the form of radiation, creating light.

This result gives rise to an entirely new phenomenon: the production of light from gravity alone. There's no situation in the present-day universe that could allow this process to happen, but the researchers have shown that the early universe was a far stranger place than we could possibly imagine.

Graviton to photon conversion via parametric resonance

https://www.sciencedirect.com/science/article/pii/S2212686423000365...

Comment by Dr. Krishna Kumari Challa on April 11, 2023 at 12:06pm

13 volcanoes seen from space

Have you ever wondered what a volcano looks like from space? Today, we’re counting down our picks of the most impressive volcanoes around the world – captured by satellites.

Comment by Dr. Krishna Kumari Challa on April 11, 2023 at 11:58am

Identifying cancer genes' multiple personalities

Mutations in our genes can lead to severe problems, like colon or liver cancer. But cancer is very complex. Mutations in the same genes can lead to different subtypes of tumors in different people. Currently, scientists don't have a good way to produce such tumor subtypes for study in the lab.

Now researchers have created a new method to model certain liver cancer tumour subtypes using the gene-editing tool CRISPR-Cas9.

Genes contain the information our bodies need to create proteins. Highly similar proteins produced from the same gene are called isoforms. Different isoforms generate different tumours.  This process is known as exon skipping, where multiple parts of a gene are stitched together to make a different version of a protein.

Everyone thinks that cancer is just one type. But with different isoforms, you can end up with cancer subtypes that have different characteristics. That is why cancer is so difficult to understand and treat. 

Researchers now produced two distinct tumor subtypes by targeting a single section of the mouse gene, Ctnnb1, with CRISPR. The tool is mostly used to inhibit gene function. This is the first time CRISPR has been used to generate different cancer-causing gain-of-function mutations in mice. These mutations enhance protein activity to promote tumour growth. The team sequenced each tumor subtype to figure out which isoform was associated with the differences they observed.

Scientists produced two distinct tumor subtypes by targeting a single section of the mouse gene, Ctnnb1, with CRISPR. The tool is mostly used to inhibit gene function. This is the first time CRISPR has been used to generate different cancer-causing gain-of-function mutations in mice. These mutations enhance protein activity to promote tumour growth. The team sequenced each tumour subtype to figure out which isoform was associated with the differences they observed.

Next, to confirm that these isoforms actually caused the variances, they produced them in the mouse without using CRISPR. They found that they were indeed able to generate the two different tumor subtypes with their respective characteristics. Both of these liver tumour subtypes are also found in humans.

The mutations these researchers targeted can lead to colon and liver cancers. 

Targeting exon skipping has emerged as a potential therapeutic approach for treating cancer and other diseases.

This work gets closer to find a cure for these cancers.

Haiwei Mou et al, CRISPR ‐induced exon skipping of β‐catenin reveals tumorigenic mutants driving distinct subtypes of liver cancer, The Journal of Pathology (2023). DOI: 10.1002/path.6054

Comment by Dr. Krishna Kumari Challa on April 11, 2023 at 11:35am

Engineered plants produce sex perfume to trick pests and replace pesticides

By using precision gene engineering techniques, researchers at the Earlham Institute in Norwich have been able to turn tobacco plants into solar-powered factories for moth sex pheromones.

Critically, they've shown how the production of these molecules can be efficiently managed so as not to hamper normal plant growth.

Pheromones are complex chemicals produced and released by an organism as a means of communication. They allow members of the same species to send signals, which includes letting others know they're looking for love.

Farmers can hang pheromone dispersers among their crops to mimic the signals of female insects, trapping or distracting the males from finding a mate. Some of these molecules can be produced by chemical processes but chemical synthesis is often expensive and creates toxic byproducts.

Synthetic biology applies engineering principles to the building blocks of life, DNA. By creating genetic modules with the instructions to build new molecules, researchers  can turn a plant such as tobacco into a factory that only needs sunlight and water.

Synthetic biology can allow us to engineer plants to make a lot more of something they already produced, or we can provide the genetic instructions that allow them to build new biological molecules, such as medicines or these pheromones.

Now they have engineered the tobacco plant to produce  moth sex pheromones. 

The same plant has previously been engineered to produce ebola antibodies and even coronavirus-like particles for use in COVID vaccines.

The Group built new sequences of DNA in the lab to mimic the moth genes and introduced a few molecular switches to precisely regulate their expression, which effectively turns the manufacturing process on and off.

An important component of the new research was the ability to fine tune the production of the pheromones, as coercing plants to continuously build these molecules has its drawbacks: As researchers increase the efficiency, too much energy is diverted away from normal growth and development.

However, this new research provides a way to regulate gene expression with much more subtlety

In the lab, the team set about testing and refining the control of genes responsible for producing the mix of specific molecules that mimic the sex pheromones of moth species, including navel orange worm and cotton bollworm moths. They showed that copper sulfate could be used to finely tune the activity of the genes, allowing them to control both the timing and level of gene expression. This is particularly important as copper sulfate is a cheap and readily-available compound already approved for use in agriculture. They were even able to carefully control the production of different pheromone components, allowing them to tweak the cocktail to better suit specific moth species. The researchers  have shown they can control the levels of expression of each gene relative to the others.

Nicola Patron et al, Tunable control of insect pheromone biosynthesis in Nicotiana benthamiana, Plant Biotechnology (2023).

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