Emmanuelle Charpentier And Jennifer Doudna Sharpened Mother Nature’s Genetic Scissors And Won The Nobel For It

November 3, 2020 by Kristina Panos 8 Comments

It sounds like science fiction — and until 2012, the ability to cheaply and easily edit strings of DNA was exactly that. But as it turns out, CRISPR/Cas9 gene editing is a completely natural function in which bacteria catalogs its interactions with viruses by taking a snippet of the virus’ genetic material and filing it away for later.

Now, two women have won the 2020 Nobel Prize in Chemistry “for developing a method for genome editing”. Emmanuelle Charpentier and Jennifer Doudna leveraged CRISPR into a pair of genetic scissors and showed how sharp they are by proving that they can edit any string of DNA this way. Since Emmanuelle and Jennifer published their 2012 paper on CRISPR/Cas9, researchers have used these genetic scissors to create drought-resistant plants and look for new gene-based cancer therapies. Researchers are also hoping to use CRISPR/Cas9 to cure inherited diseases like Huntington’s and sickle cell anemia.

The discovery started with Emmanuelle Charpentier’s investigation of the Streptococcus pyogenes bacterium. She was trying to understand how its genes are regulated and was hoping to make an antibiotic. Once she teamed up with Jennifer Doudna, they found a scientific breakthrough instead.

Dr. Emmanuelle Charpentier via Wikimedia Commons

Emmanuelle Charpentier Fights Flesh-Eating Bacteria

Emmanuelle Charpentier was born December 11th, 1968 in Juvisy-sur-Orge, France. She studied biochemistry, microbiology, and genetics at the Pierre and Marie Curie University, which is now known as Sorbonne University. Then she received a research doctorate from Institut Pasteur and worked as a university teaching assistant and research scientist. Dr. Charpentier is currently a director at the Max Planck Institute for Infection Biology in Berlin, and in 2018, she founded an independent research unit.

Upon completion of her doctorate, Dr. Charpentier spent a few years working in the States before winding up at the University of Vienna where she started a research group. Her focus was still on the bacteria Streptococcus pyogenes, which causes millions of people to suffer through infections like tonsillitis and impetigo each year. It also causes sepsis, which officially makes it a flesh-eating bacterium.

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Andrea Ghez Gazes Into Our Galaxy’s Black Hole

October 13, 2020 by Kristina Panos 21 Comments

Decades ago, Einstein predicted the existence of something he didn’t believe in — black holes. Ever since then, people have been trying to get a glimpse of these collapsed stars that represent the limits of our understanding of physics.

For the last 25 years, Andrea Ghez has had her sights set on the black hole at the center of our galaxy known as Sagittarius A*, trying to conclusively prove it exists. In the early days, her proposal was dismissed entirely. Then she started getting lauded for it. Andrea earned a MacArthur Fellowship in 2008. In 2012, she was the first woman to receive the Crafoord Prize from the Royal Swedish Academy of Sciences.

Now Andrea has become the fourth woman ever to receive a Nobel Prize in Physics for her discovery. She shares the prize with Roger Penrose and Reinhard Genzel for discoveries relating to black holes. UCLA posted her gracious reaction to becoming a Nobel Laureate.

A Star is Born

Andrea Mia Ghez was born June 16th, 1965 in New York City, but grew up in the Hyde Park area of Chicago. Her love of astronomy was launched right along with Apollo program. Once she saw the moon landing, she told her parents that she wanted to be the first female astronaut. They bought her a telescope, and she’s had her eye on the stars ever since. Now Andrea visits the Keck telescopes — the world’s largest — six times a year.

Andrea was always interested in math and science growing up, and could usually be found asking big questions about the universe. She earned a BS from MIT in 1987 and a PhD from Caltech in 1992. While she was still in graduate school, she made a major discovery concerning star formation — that most stars are born with companion star. After graduating from Caltech, Andrea became a professor of physics and astronomy at UCLA so she could get access to the Keck telescope in Mauna Kea, Hawaii.

The Keck telescopes and the Milky Way. Image via Flickr

The Center of the Galaxy

Since 1995, Andrea has pointed the Keck telescopes toward the center of our galaxy, some 25,000 light years away. There’s a lot of gas and dust clouding the view, so she and her team had to get creative with something called adaptive optics. This method works by deforming the telescope’s mirror in real time in order to overcome fluctuations in the atmosphere.

Thanks to adaptive optics, Andrea and her team were able to capture images that were 10-30 times clearer than what was previously possible. By studying the orbits of stars that hang out near the center, she was able to determine that a supermassive black hole with four millions times the mass of the sun must lie there. Thanks to this telescope hack, Andrea and other scientists will be able to study the effects of black holes on gravity and galaxies right here at home. You can watch her explain her work briefly in the video after the break. Congratulations, Dr. Ghez, and here’s to another 25 years of fruitful research.

This Year’s Nobel Prizes Are Straight Out Of Science Fiction

October 10, 2018 by Steven Dufresne 22 Comments

In the 1966 science fiction movie Fantastic Voyage, medical personnel are shrunken to the size of microbes to enter a scientist’s body to perform brain surgery. Due to the work of this year’s winners of the Nobel Prize in Physics, laser tools now do work at this scale.

Arthur Ashkin won for his development of optical tweezers that use a laser to grip and manipulate objects as small a molecule. And Gérard Mourou and Donna Strickland won for coming up with a way to produce ultra-short laser pulses at a high-intensity, used now for performing millions of corrective laser eye surgeries every year.

Here is a look at these inventions, their inventors, and the applications which made them important enough to win a Nobel.

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Barbara McClintock: Against The Genetic Grain

December 28, 2017 by Steven Dufresne 8 Comments

The tale of much of Barbara McClintock’s life is that of the scientist working long hours with a microscope seeking to solve mysteries. The mystery she spent most of her career trying to solve was how all cells in an organism can contain the same DNA, and yet divide to produce cells serving different functions; basically how cells differentiate. And for that, she got a Nobel prize all to herself, which is no small feat either.

Becoming a Scientist

Human chromosomes, long strands of DNA by Steffen Dietzel CC BY-SA 3.0

McClintock was born on June 16, 1902, in Hartford, Connecticut, USA. From age three until beginning school, she lived with her aunt in Brooklyn, New York while her father strove financially to start up a medical practice. She was a solitary and independent-minded child, a trait she later called her “capacity to be alone”.

In 1919, she began her studies at Cornell’s College of Agriculture and took her first course in genetics in 1921. A year later, due to the interest she showed in genetics, she was invited to take the graduate genetics course at Cornell. It was here that she became interested in the new field of cytogenetics, specifically of maize or corn. Cytogenetics studies how the chromosomes relate to cell behavior, particularly during cell division. Chromosomes are the long strands of DNA within the nucleus of every cell and shown here in the photo at a time when they are condensed, or coiled up.

While still at Cornell she developed a number of methods for visualizing and characterizing maize which ended up in textbooks. She also became the first to describe the morphology of the ten maize chromosomes, basically their form and structural relationships, which then allowed her to discover more about the chromosomes. One of her colleagues observed that ten of the seventeen significant advances made in the field at Cornell between 1929 and 1935 were hers. This was only the first step in what would be the remarkable career of a very well respected scientist.

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Maria Goeppert-Mayer: The Other Nobel Prize Winner

November 14, 2017 by Steven Dufresne 20 Comments

Maria Goeppert-Mayer was one of only two women to win the Nobel prize for physics thus far, the other being Marie Curie. And yet her name isn’t anywhere near as well known as Marie Curie’s. She also worked on the Manhattan Project and spent time during her long career with Enrico Fermi, Max Born, Edward Teller, and many other physics luminaries.

She was “other” in another way too. She followed her husband from university to university, and due to prevailing rules against hiring both husband and wife, often had to take a non-faculty position, sometimes even with no salary. Yet being the other, or plus-one, seemed to give her what every pure scientist desires, the freedom to explore. And explore she did, widely. She was always on the cutting edge, and all the time working with the leading luminaries of physics. For a scientist, her story reads like it’s too good to be true, which is what makes it so delightful to read about.

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Rita Levi-Montalcini Had Nerves Of Steel

October 31, 2017 by Kristina Panos 26 Comments

When we think of role models, it’s easy to categorize them narrowly on the basis of their skill set. We might say that he’s a great mathematician, or that she is an excellent chemist. Some role models are admirable on a deeper, human level. These are the kinds of heroes who obliterate all the obstacles dropped in front of them to tirelessly pursue their interests and devote their lives to doing the kind of stuff that makes the world better for everyone.

Italian Nobel Laureate Rita Levi-Montalcini is this kind of role model. Her scientific curiosity and unconventional thinking led her to discover nerve growth factor (NGF), a naturally occurring protein which we now know is responsible for nerve growth and regulation. Rita’s discovery provided great insight into the way the nervous system develops. The discoveries that she made underlie much of modern research into neurologically degenerative diseases like Alzheimer’s and cancer, and NGF is used experimentally the treatment of both.

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Retrotechtacular: The Genesis Of The Transistor

January 14, 2014 by Kristina Panos 36 Comments

Few births are easy. Even fewer result in a Nobel Prize, and hardly any at all are the work of three men. This 1965 film from the AT&T archives is a retrospection on the birth of the transistor nine years after its creators, [Walter Brattain], [John Bardeen], and [William Shockley] received a Nobel Prize in Physics for their discovery and implementation of the transistor effect.

The transistor is the result of the study of semiconductors such as germanium. Prior to the research that led directly to the transistor, it was known that the conductivity of semiconductors increases when their temperature is raised. The converse is true for metals such as tungsten. Semiconductor conductivity also increases when they are exposed to light. Another key to their discovery is that when a metal such as copper is in contact with a semiconductor, conductivity is less in one direction than the other. This particular property was exploited in early radio technology as seen in crystal radios, for copper oxide rectifiers used in telephony, and for microwave radar in WWII.

After WWII, AT&T’s Bell Labs put a lot of time and research into the study of semiconductors, as their properties weren’t fully understood. Researchers focused on the simplest semiconductors, silicon and germanium, and did so in two areas: bulk properties and surface properties. During this time, [Shockley] proposed the field effect, supposing that the electrons near the surface of a semiconductor could be controlled under the influence of an external electric field.

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