Color electron micrograph of an endosome, a cell organelle. Credit: Ranjan Ramachandra, UCSD
As his Christmas gift to himself each year, the late biochemist Roger Tsien treated himself to two weeks of uninterrupted research in his lab. This image is a product of those annual sojourns. While it may look like a pine wreath dotted with crimson berries, it is in fact one of the world’s first color electron micrographs—and the method used to create it may dramatically advance cell imaging.
Electron microscopy (EM) is a time-honored technique for visualizing cell structures that uses beams of accelerated electrons to magnify objects up to 10 million times their actual size. Standard EM images are in grayscale and any color is added in with computer graphics programs after the image is made. With their new technique, Tsien, who received a Nobel Prize for his development of green fluorescent protein into a tool for visualizing details in living cells using light microscopes, and his colleagues have found a way to incorporate color labeling directly into EM. Continue reading “Cool Image: Adding Color to the Gray World of Electron Microscopy”
In the 13 years since the sequencing of the human genome, the list of “omes” has proliferated. Drop us a comment with your favorite ome—we may feature it in a follow-up post next month.
Have you ever collected coins, cards, toy trains, stuffed animals? Did you feel the need to complete the set? If so, then you may be a completist. A completist will go to great lengths to acquire a complete set of something.
Scientists can also be completists who are inspired to identify and catalog every object in a particular field to further our understanding of it. For example, a comprehensive parts list of the human body—and of other organisms that are important in biomedical research—could aid in the development of novel treatments for diseases in the same way that a parts list for a car enables auto mechanics to build or repair a vehicle.
More than 15 years ago, scientists figured out how to catalog every gene in the human body. In the years since, rapid advances in technology and computational tools have allowed researchers to begin to categorize numerous aspects of the biological world. There’s actually a special way to name these collections: Add “ome” to the end of the class of objects being compiled. So, the complete set of genes in the body is called the “genome,” and the complete set of proteins is called the “proteome.”
Below are three -omes that NIH-funded scientists work with to understand human health.
Genome
Illustration of the entire outer shell of the bacteriophage MS2. Credit: Wikimedia Commons, Naranson.
The genome is the original -ome. In 1976, Belgium scientists identified all 3,569 DNA bases—the As, Cs, Gs and Ts that make up DNA’s code—in the genes of bacteriophage MS2, immortalizing this bacteria-infecting virus as possessing the first fully sequenced genome.
Over the next two decades, a small handful of additional genomes from other microorganisms followed. The first animal genome was completed in 1998. Just 5 years later, scientists identified all 3.2 billion DNA bases in the human genome, representing the work of more than 1,000 researchers from six countries over a period of 13 years. Continue reading “There’s an “Ome” for That”
Credit: Pablo Tsukayama, Ph.D., Washington University School of Medicine
Gautam Dantas Born: Mumbai, India Most proud of: His family, which brings him joy and pride Favorite lab tradition: OOFF! Official Optional Formal Fridays, when members of his lab can dress up, eat bread—made in the lab’s own bread machine—and drink beer and wine together at the end of the day When not in the lab, he: Enjoys home brewing, pickling and canning, and spending time with his wife and children. He also attends musical performances, including those of his wife, who sings in the St. Louis Symphony Chorus Advice to aspiring scientists: Pursue hobbies, take risks, explore beyond your comfort zone. “You can do a Ph.D., but also have other experiences.” He says his own outside activities refine his focus in the lab, keep him grounded and help him be an empathetic mentor to his students. Plus, he met his wife while singing in the chorus of Macalester College in St. Paul, Minnesota
When I Grow Up…
Gautam Dantas remembers the day in 10th grade when he first wanted to be a scientist. It was the day he had a new biology teacher, a visiting researcher from the U.S. The teacher passionately described his own biochemical studies of how organisms live together in communities. By the end of the class, Dantas had resolved to earn a Ph.D. in biochemistry.
He ended up doing much more—gaining expertise in computational biology, protein design and synthetic biology. He now combines his skills and knowledge in multifaceted research that spans four departments at Washington University in St. Louis. His goal: to better understand and help combat a vital public health threat—drug-resistant bacteria.
“Our motivation is that we are living in the antibiotic era, and antibiotic resistance is getting out of control,” Dantas says. “We have very few new antibiotics we can use, so we’re kind of scrambling [to find new ways to treat bacterial diseases].”
His research focuses on one of the groups most vulnerable to bacterial infections—newborn babies.
According to his lab’s website, the research is “at the interface of microbial genomics, ecology, synthetic biology, and systems biology,” and it aims “to understand, harness, and engineer the biochemical processing potential of microbial communities.” They do it by scrounging around in infant diapers.
Antibiotic Angst
Since their introduction in the 1940s, antibiotic drugs have saved countless lives. Simultaneously, they weeded out strains of bacteria easily killed by the drugs, allowing drug-resistant strains to thrive. Every year, at least 2 million people in the U.S. become infected and at least 23,000 die from drug-resistant bacteria, according to the Center for Disease Control and Prevention. Continue reading “The Irresistible Resistome: How Infant Diapers Might Help Combat Antibiotic Resistance (sort of)”
Students from Connecticut to Washington State and points in between peppered our experts with questions during the recent live Cell Day web chat. They fielded questions about cell structures, microscopes and other tools, life as a scientist, and whether there are still discoveries to be made in cell biology. One of the Cell Day moderators, Jessica Faupel-Badger, even gave a shout-out to the Biomedical Beat blog as a great way to keep up with new and exciting discoveries being made every day. Thanks!
The full transcript with all the questions and answers is now available. We’ve recapped some of the highlights below.
[Check out our Facebook Live post-chat video for a bonus answer to the question “If you put lizard DNA into human cells, could humans regrow their limbs?”]
Being a Scientist
Prior to joining NIGMS in 2016 as a program director, Patrick Brown, was a high school chemistry teacher in Maryland.
What do you think is the best thing about being a biologist? Why do you love your job so much? (Assuming you do!)
Patrick Brown answered: I love that question! And, I love being a scientist. There are so many things that I like about my career choice. The answer is simple—I like learning! I like learning about different living organisms and how they may be the same or different. I also really enjoy the multi-cultural aspect of science. I get to interact with so many different people from different parts of the world who are all studying different aspects of science that are just as interesting as my own, and we are all interested in knowing more about life.
How did you know that biology was the career for you? In other words, what motivated you to become a biologist?
Amy Kullas answered: I remember being in my high school biology class, gazing through a microscope, and seeing the mixture of beautiful purple and pink cocci after performing my first Gram stain. It was at that moment that I got hooked on science. I majored in microbiology in college and then went on to graduate school.
What does a typical day at work look like?
Amicia Elliott answered: The truth is that every day at work is an adventure. A typical day includes some of the following things: reading scientific papers, thinking about and designing experiments (my favorite part!), carrying out those experiments, data analysis and discussing results. Scientists work long hours to accomplish all of these things, but it is mostly a labor of love!
In a 2014 Molecular Cell paper, NIGMS Director Jon Lorsch and colleagues determined the structure of initiation complexes.
What was the most interesting experiment you have conducted?
Jon Lorsch answered: In my lab, we study how proteins are synthesized by the eukaryotic ribosome. We have learned a great deal about how the ribosome and the proteins that help it (called translation factors) find the start codon in the messenger RNA. Recently, in collaboration with a group in the UK, we used cryo-electron microscopy to determine the three-dimensional structure of various ‘initiation complexes’ – the small subunit of the ribosome bound to mRNA, tRNA and initiation factors. Being able to see how this process works in three dimensions is amazing!
Nearly 10 percent of the human genome is derived from the genes of viruses. Credit: Stock image.
When viruses infect us, they can embed small chunks of their genetic material in our DNA. Although infrequent, the incorporation of this material into the human genome has been occurring for millions of years. As a result of this ongoing process, viral genetic material comprises nearly 10 percent of the modern human genome. Over time, the vast majority of viral invaders populating our genome have mutated to the point that they no longer lead to active infections. But they are not entirely dormant.
Sometimes, these stowaway sequences of viral genes, called “endogenous retroviruses” (ERVs), can contribute to the onset of diseases such as cancer. They can also make their hosts susceptible to infections from other viruses. However, scientists have identified numerous cases of viral hitchhikers bestowing crucial benefits to their human hosts—from protection against disease to shaping important aspects of human evolution, such as the ability to digest starch.
For a virus to successfully make copies of itself inside a host cell, it needs molecular tools similar to the ones its host normally uses to translate genes into proteins. As a result, viruses have tools meticulously shaped by evolution to commandeer the protein-producing machinery of human cells.
An exhibit called “Minerals in Medicine” opened at the NIH Clinical Center last month (see slideshow). The display features a fascinating overview of how dozens of minerals are used to create drugs and medical instruments useful in treating disease and maintaining health. The minerals ranged from commonplace ones like quartz, which is used to make medical instruments, to more exotic ones like hubnerite, a source of the metal tungsten, which is used in radiation shielding.
Inspired by this collection, which is co-sponsored by NIH and the Smithsonian Institution, we highlight here examples of “Metals in Medicine.”
Copper and Fat Metabolism
Fluorescent imaging of copper in white fat cells from mice. The left panel shows fat cells with normal levels of copper, and the right panel shows fat cells deficient in copper. Credit: Lakshmi Krishnamoorthy and Joseph Cotruvo Jr., University of California, Berkeley.
What does a metal like copper have to do with our ability to breakdown fat? Researchers explored this question by observing mice with Wilson’s disease—a rare, inherited condition that causes copper to accumulate in the liver, brain and other vital organs. The mice with the condition usually have larger deposits of fat compared to healthy mice. To confirm that fat metabolism is somehow compromised in these mice, the researchers treated them with a drug that induces the breakdown of fat. And indeed they found that less fat was metabolized in mice with the disease.
In an effort to investigate what role copper may be playing in fat metabolism, the researchers examined adipose tissue, or fat, cells under a microscope to track the metal’s interactions with various proteins in the cell. They discovered that copper inhibits an enzyme called PDE3. This enzyme usually prevents another enzyme called cAMP from helping to break down fat. The researchers concluded that copper actually promotes fat metabolism. This work shows that transition metal nutrients can play signaling roles, which has been previously thought to be restricted to alkali and alkaline earth metals like sodium, potassium and calcium.
For several years, we’ve used this blog to highlight pictures we think are cool, scientifically relevant and visually striking. The images were created by NIGMS-funded researchers in the process of doing their research. Many come from our Life: Magnified collection, which features dozens of stunning photos of life, close-up. We’ll continue to bring you interesting images and information here on Biomedical Beat, but if you can’t get enough of them, we have a new way to share our visual content with you: Instagram.
We’re pleased to announce the launch of our NIGMS Instagram account. We’ll highlight gorgeous images, and bring you the science behind them—straight from our mobile device to yours. Instagram lets us label our images with subject-specific hashtags. You can find our pictures by going on Instagram and searching for #NIGMS. If you’re already an Instagram user, you can follow us @NIGMS_NIH. You can even see our page using a web browser at https://www.instagram.com/nigms_nih/. Let us know what you think!
Also, if you have any stunning images or videos that relate to scientific areas supported by NIGMS, please send them to us. They might end up on our Instagram feed!
We need zinc. It’s an essential nutrient for growth and development, fending off invading microbes, healing injuries, and all sorts of cellular processes. We get the mineral through our diet, but people in certain parts of the world don’t get enough. Researchers study how plants acquire and process zinc, hoping to find ways to increase the nutrient in food crops. Using synchrotron X-ray fluorescence technology, scientists created this heat map of zinc in a leaf from a plant called Arabidopsis thaliana (zinc levels from lowest to highest: blue, green, red, white). Credit: Suzana Car and Mary Lou Guerinot, Dartmouth College. #science#biology#research#botany#plant#arabidopsis#zinc#microscopy#synchrotron#x-ray#modelorganism#leaf#heatmap#scienceisbeautiful#nigms#nih
Beautiful brain! This image shows the cerebellum, which is the brain’s locomotion control center. Every time you shoot a basketball, tie your shoe or chop an onion, your cerebellum fires into action. Found at the base of your brain, the cerebellum is a single layer of tissue with deep folds like an accordion. People with damage to this region of the brain often have difficulty with balance, coordination and fine motor skills. Credit: Tom Deerinck and Mark Ellisman, NCMIR #science#biology#research#cerebellum#neuroscience#neurobiology#brain#brains#brainimages#neuroanatomy#microscopy#scienceisbeautiful#sciart#nigms#nih#NCMIR#UCSD
Retinal ganglion cells in the mouse retina that do (bright, yellow spots throughout) and do not (blue streaks, mostly along the edges) contain a specific gene that scientists introduced with a virus. Credit: Kenyoung (“Christine”) Kim, Wonkyu Ju and Mark Ellisman, National Center for Microscopy and Imaging Research, University of California, San Diego.
What looks like the gossamer wings of a butterfly is actually the retina of a mouse, delicately snipped to lay flat and sparkling with fluorescent molecules. Researchers captured this image while investigating the promise of gene therapy for glaucoma, a progressive eye disease. It all happened at the National Center for Microscopy and Imaging Research (NCMIR) at the University of California, San Diego.
Glaucoma is the leading cause of irreversible blindness. It is characterized by the slow, steady death of certain nerve cells in the retina. If scientists can prevent the death of these cells, which are called retinal ganglion cells, it might be possible to slow the progression of glaucoma. Some researchers are examining the possibility of using gene therapy to do just that.
A major challenge of gene therapy is finding a way to get therapeutic genes into the right cells without damaging the cells in any way. Scientists have had success using a non-disease-causing virus (adeno-associated serotype 2) for this task. Continue reading “Lighting Up the Promise of Gene Therapy for Glaucoma”
Female brown recluse spider. Credit Matt Bertone, North Carolina State University.
This Halloween, you’re not likely to see many trick-or-treaters dressed as spiders. Google Trends pegs “Spider” as the 87th most searched-for Halloween costume, right between “Hippie” and “The Renaissance.” But don’t let your guard down. Spiders are everywhere.
“I grew up on a farm in Indiana and had the luxury of exploring and turning over rocks and being curious. Any feelings of being grossed out by spiders were rapidly replaced by my feelings of awe for how amazing and diverse these creatures are.”– Greta Binford”
More than 46,000 species of spiders creepy crawl across the globe, on every continent except Antarctica. Each species produces a venom composed of an average of 500 distinct toxins, putting the conservative estimate of unique venom compounds at more than 22 million. This staggering diversity of venoms, collectively referred to as the venome, has only begun to be explored. Continue reading “Exploring the Evolution of Spider Venom to Improve Human Health”
The outside of every cell on Earth—from the cells in your body to single-celled microorganisms—is blanketed with a coat of carbohydrates, or sugar molecules, that extend from the cell surface, branching off and bending as they interface with the extra-cellular space. The specific patterns in which these carbohydrates are arranged serve as an ID code that help cells recognize each other. For example, human liver cells have one pattern, while human red blood cells another. Certain diseases can even alter the pattern of surface carbohydrates, which is one way the body can recognize damaged cells. On foreign cells, including invading bacteria such as Streptococcus pneumoniae, the carbohydrate coat is even more distinct.
Laura Kiessling, a professor of chemistry at the University of Wisconsin, Madison, studies how carbohydrate coats are assembled and how cells use these coats to tell friend from foe. The implications of her research suggest strategies for targeting tumors, fighting diseases of inflammation and, as she discusses in this video, developing new classes of antibiotics.
Subscribe to Biomedical Beat
Get our latest blog posts
delivered straight to your inbox! Sign Up Here
, the research is “at the interface of microbial genomics, ecology, synthetic biology, and systems biology,” and it aims “to understand, harness, and engineer the biochemical processing potential of microbial communities.” They do it by scrounging around in infant diapers.
