Transgenetically Speaking

Image Source: NY Times. Melissa Bell.

In 2011, researchers from the renowned Mayo Clinic pushed science to its very limit in order to produce… a glow in the dark cat. While this might seem like a waste of time and resources (or an internet joke), the creation of this kind of cat is a marvel of modern transgenics.

Transgenics?

Transgenics is the study and development of organisms with artificially implanted genes from other creatures. The Mayo Clinic cat could glow in the dark because it possessed a gene for fluorescence that was taken from jellyfish. There has also been, for instance, a goat with a spider gene that produces milk with traces of spider silk. There are even transgenic plants, much like the synthetically nutritional golden rice.

Making the Genetic Magic Happen

Image Source: Science Creative. Helmut Kae.

There are many different ways to create transgenic organisms, but one of the most common is to just inject the gene into an embryo. Scientists isolate the gene of interest, or transgene, from another organism and inject it into a fertilized embryo in a laboratory setting. This embryo (with the transgene) is then implanted into a surrogate organism of the same species until eventually the transgenic animal is born. The con to this method is that there is a very low chance the embryo will survive the pregnancy or even incorporate the transgene in the first place. This makes the transgenic approach a very costly and time-consuming process.

What’s the Point?

Golden rice on the left, white rice on the right.
Image Source: Gates Foundation.

Scientists don’t create transgenic organisms so they can take over the world or develop genetic monstrosities; in some cases the organisms are used to directly benefit others. Golden rice, for instance, is part of a project to prevent malnutrition in poorer countries. Many adults, much less children, in these nations can only afford one bowl of rice a day. One bowl of normal white rice confers very few nutrients and can lead to severe nutrient deficiencies or death if not supplemented with other foods. Golden rice, on the other hand, was developed to be a powerhouse of nutritional goodness and provide plenty of health benefits even in a single bowl. Its signature golden color actually comes from the beta-carotene (or vitamin A precursor) it produces.

The main purpose of the glowing cat study was to track an AIDS resistance gene. The Mayo Clinic scientists coupled the resistance and fluorescence genes together in the cat, meaning that both would be incorporated into the cat's genome. The fluorescence was a signal that the cat successfully incorporated the AIDS resistance gene, helping to further research for a cure to the disease. A worthy goal with a pretty unique cat on the side.

Rise of the Zombie Ants

Image source: Flickr. Xenomurphy.

America has gone crazy for zombies. In the past few years there has been a huge rise in media portraying zombies, whether they take the form of video games, TV shows, books, or movies. The only thing that can console people terrified of zombies is the fact that zombies don’t exist. At least the public thought zombies did not actually exist until a discovery was made in 2011.

Zombie Ground Zero

Image source: Flickr. Armed Forces Pest Management Board.

Carpenter ants (technically Camponotus leonardi) in Thailand are being “zombified” by a unique fungus in the genus Ophiocordyceps. The “zombification”process starts when an ant comes into contact with one of the fungus’ microscopic spores. In the beginning, right after exposure, the ant behaves normally as if nothing happened. During this time, the fungus grows within the ant and slowly degrades muscles and other internal organs. Eventually the fungus takes over the brain, gaining complete control of the ant’s body and movement.

Spreading the Undead Love

Image source: National Geographic. David P. Hughes.

Once the fungus is in charge the zombie ant moves to a moist area of the forest and bites down on the vein of a leaf. At this point, the fungus moves into the ant’s mouth and breaks apart muscles so that the ant can never let go of the leaf. After a few days the fungus bursts out of the ant in the form of a fruiting body that releases spores. These spores are then (unfortunately) picked up by other ants, causing the cycle of life and “undeath” to repeat itself.

Finding a Cure

This fungus might be a little disturbing to think about, but so far there have been no instances of it affecting any other organisms aside from carpenter ants. According to entomologist David Hughes, there is also a glimmer of hope and salvation for infected ants. Even if an ant picks up a Ophiocordyceps spore, it can still lead a normal life so long as it encounters another, mystery fungus. This fungus is unique in that it can efficiently kill off Ophiocordyceps without harming the host ant, stopping the "zombification" before it’s too late. Thankfully, for now, the threat of a zombie apocalypse is only real in the movies.

A Mythbusters Thanksgiving

Image Source: Flickr. Joits.

Even if there were dozens of casseroles, potato concoctions, and pies, Thanksgiving dinner just wouldn’t be complete without turkey. It’s a prime American tradition to meet family, watch football, eat massive amounts of turkey (among other things), and then fall into a sort of food coma. But why does the food coma occur in the first place?

Image Source: HowStuffWorks.

Turkeys and Tryptophan

The most common reasoning for the Thanksgiving food coma is that it is the result of massive tryptophan intake. Tryptophan is an amino acid (or building block for proteins) commonly found in turkey that is used in the production of serotonin, a hormone that triggers sleepiness and relaxation in people. Since people eat a lot of turkey on Thanksgiving, it’s assumed that they also process a lot of tryptophan and serotonin. The combination of these two compounds allegedly results in the infamous food coma.

Debunking Tryptophan

Image Source: Flickr. Hectichousehold.

Other studies have debunked the tryptophan-sleep hypothesis based on two different reasons.

1) Tryptophan is abundant not only in turkey, but all poultry.

Following this factoid, it would be logical to assume that a person should fall into a similar food coma after eating a lot of chicken. However, that chicken-induced sleep event never occurs.

2) Tryptophan only triggers serotonin production in an empty stomach

When tryptophan is present in a stomach full of other foods and amino acids, it essentially has to compete with those other molecules to induce some sort of effect on the body. As a result, the serotonin production from tryptophan in someone with a full stomach is much more reduced in comparison to that of someone with an empty stomach. Since Thanksgiving is one of the few days it’s socially acceptable (and encouraged) to eat a lot, there is no way someone would have an empty stomach so tryptophan could function properly.

A Smorgasbord of Possibilities

While there is proof that tryptophan may not be the sleep-inducing agent, some researchers believe that a mix of carbohydrates (from essentially everything on the Thanksgiving menu) and tryptophan can result in sleepiness. Other scientists think that the process of digesting all of the food from the day takes a greater toll on the body, resulting in the food coma. There are a lot of ideas about the situation, but no concrete explanation for why it happens just yet.

An Aid to HIV

Image Source: Flickr. Kristian Hay

In recent years there has been a strong push toward safe sex in order to prevent the spread of STDs, or sexually transmitted diseases. However, when Americans from ages 18 to 64 were asked about STDs most could list a few major diseases but 12% could not list even one. Only 23% mentioned chlamydia, the most prevalent STD in the nation. It turns out that Americans may realize that they should use condoms and other tools for safe sex, but they don’t exactly know the reasons why.

Image Source: Kaiser Family Foundation.

Sexually Transmitted What Now?

These misconceptions even transfer to HIV, one of the most publicized STDs in the world. 34% of the same set of Americans thought that HIV could be transmitted via sharing a drinking glass, touching a toilet seat, or being in a pool with someone who is HIV+. Most don’t even realize there is a difference between HIV and AIDS.

The Facts

Image Source: Reuters.

So what are HIV and AIDS? HIV stands for Human Immunodeficiency Virus, a condition that be spread only through sexual contact or exposure to infected blood. This virus infects and kills the immune system’s CD4⁺ T cells that normally deal with infections, making it so that a body has trouble responding to viruses or bacteria. Once HIV kills enough T cells, it turns into AIDS, the Acquired Immune Deficiency Syndrome. At this stage, so many T cells have been destroyed that it is impossible for the body to fight any other infections, making even the common cold a deadly illness.

Looking to the Future

HIV works slowly, so it can take years for it to destroy enough of the immune system to be problematic or even noticeable. There are a lot of symptoms that can indicate HIV infection, but they can be easily mistaken for other diseases. The only real way for people to know if they have the disease is to get tested for it. As of now there is no cure for HIV, only a concoction of medicines that can slow down its progression to AIDS from years to decades. There is ongoing global research for a vaccine, though, and one group of South African scientists recently discovered a potential wayto target the virus itself. For now, though, all people can do is to be safe (and knowledgeable) when having sex.

Do You Believe in Magic?

With Halloween quickly approaching, it’s time to reevaluate whether or not there’s magic in the air. Some people may wait by their mailboxes for a Hogwarts acceptance letter. Others may go on haunted tours and wait to see the supernatural. Even fewer may order some fruit online. Not just any fruit, though, magic fruit.

It's a Miracle!

Image source: Flickr. 3Point141

The fruit in question is Synsepalum dulcificum, a berry more commonly known as the miracle fruit. While this berry will not enable you to fly, it still has a little bit of a special kick. If you eat this berry, then everything and anything sour will taste just like candy for a limited period of time. Lemons taste like ice cream, Tabasco sauce like a sweet glaze, and (for those with a refined palate) oysters like bubblegum. This berry has gotten so popular in some cities that people have started throwing “flavor-tripping parties” to try out its magical effects.

Sour = Sweet?

Image Source: Nature. 

The miracle fruit, sadly, does not work because of magic. Instead, it converts that lip-puckering sour taste into a sweet flavor with the help of a protein known as miraculin. The miracle fruit has an abundant supply of miraculin, which binds to special receptors in taste buds on the human tongue. These receptors normally distinguish different tastes, such as sweet and sour. When miraculin is present, though, the “sweet” receptors begin to recognize sour signals as sweet. This makes the tongue think food like lemons are actually dessert, triggering those sweet taste signals.  Not everything tastes like cake, though, since miraculin only works when it is in an acidic (or sour) environment. 

Holiday Bargains

Image Source: Flickr. dadadreams

The main question after hearing about the miracle fruit is simple: where to buy it? The average cost is around $2 for a single berry, which will provide an hour of expectation-defying taste. Of course, that's only for the fresh fruit. Synsepalum dulcificum also comes in tablet form. A pack of these pills can cost up to $15, but at least they have a much longer expiration date than the real fruit. There are dozens of online providers for both forms of the berry, so it's pretty feasible to obtain. 

I've been waiting for that letter from an owl for 9 years, so I might just get a berry to experience the magic of science in the meantime.