transcriptome
A New Piece of the Alzheimer’s Puzzle
Posted on by Dr. Francis Collins
Credit: National Institute on Aging, NIH
For the past few decades, researchers have been busy uncovering genetic variants associated with an increased risk of Alzheimer’s disease (AD) [1]. But there’s still a lot to learn about the many biological mechanisms that underlie this devastating neurological condition that affects as many as 5 million Americans [2].
As an example, an NIH-funded research team recently found that AD susceptibility may hinge not only upon which gene variants are present in a person’s DNA, but also how RNA messages encoded by the affected genes are altered to produce proteins [3]. After studying brain tissue from more than 450 deceased older people, the researchers found that samples from those with AD contained many more unusual RNA messages than those without AD.
Creative Minds: Rapid Testing for Antibiotic Resistance
Posted on by Dr. Francis Collins
Ahmad (Mo) Khalil
The term “freeze-dried” may bring to mind those handy MREs (Meals Ready to Eat) consumed by legions of soldiers, astronauts, and outdoor adventurers. But if one young innovator has his way, a test that features freeze-dried biosensors may soon be a key ally in our nation’s ongoing campaign against the very serious threat of antibiotic-resistant bacterial infections.
Each year, antibiotic-resistant infections account for more than 23,000 deaths in the United States. To help tackle this challenge, Ahmad (Mo) Khalil, a researcher at Boston University, recently received an NIH Director’s New Innovator Award to develop a system that can more quickly determine whether a patient’s bacterial infection will respond best to antibiotic X or antibiotic Y—or, if the infection is actually viral rather than bacterial, no antibiotics are needed at all.
Creative Minds: The Worm Tissue-ome Teaches Developmental Biology for Us All
Posted on by Dr. Francis Collins
Credit: Coleen Murphy, Princeton University, Princeton, NJ
In the nearly 40 years since Nobel Prize-winning scientist Sydney Brenner proposed using a tiny, transparent soil worm called Caenorhabditis elegans as a model organism for biomedical research, C. elegans has become one of the most-studied organisms on the planet. Researchers have determined that C. elegans has exactly 959 cells, 302 of which are neurons. They have sequenced and annotated its genome, developed an impressive array of tools to study its DNA, and characterized the development of many of its tissues.
But what researchers still don’t know is exactly how all of these parts work together to coordinate this little worm’s response to changes in nutrition, environment, health status, and even the aging process. To learn more, 2015 NIH Director’s Pioneer Award winner Coleen Murphy of Princeton University, Princeton, NJ, has set out to analyze which genes are active, or transcribed, in each of the major tissues of adult C. elegans, building the framework for what’s been dubbed the C. elegans “tissue-ome.”
Creative Minds: Can Salamanders Show Us How to Regrow Limbs?
Posted on by Dr. Francis Collins
Jessica Whited /Credit: LightChaser Photography
Jessica Whited enjoys spending time with her 6-year-old twin boys, reading them stories, and letting their imaginations roam. One thing Whited doesn’t need to feed their curiosity about, however, is salamanders—they hear about those from Mom almost every day. Whited already has about 1,000 rare axolotl salamanders in her lab at Harvard University and Brigham and Women’s Hospital, Cambridge, MA. But caring for the 9-inch amphibians, which originate from the lakes and canals underlying Mexico City, certainly isn’t child’s play. Axolotls are entirely aquatic–their name translates to “water monster”; they like to bite each other; and they take 9 months to reach adulthood.
Like many other species of salamander, the axolotl (Ambystoma mexicanum) possesses a remarkable, almost magical, ability to grow back lost or damaged limbs. Whited’s interest in this power of limb regeneration earned her a 2015 NIH Director’s New Innovator Award. Her goal is to discover how the limbs of these salamanders know exactly where they’ve been injured and start regrowing from precisely that point, while at the same time forging vital new nerve connections to the brain. Ultimately, she hopes her work will help develop strategies to explore the possibility of “awakening” this regenerative ability in humans with injured or severed limbs.
Lyme Disease: Gene Signatures May Catch the Infection Sooner
Posted on by Dr. Francis Collins
Caption: Borrelia burgdorferi. Immunofluorescent antibodies bind to surface proteins on the bacterium that causes Lyme disease, producing fluorescent yellow, red, and green hues.
Credit: National Institute of Allergy and Infectious Diseases
Each year, thousands of Americans are bitten by deer ticks.These tiny ticks, common in and around wooded areas in some parts of the United States, can transmit a bacterium into the bloodstream that causes Lyme disease. Those infected experience fever, headache, stiff necks, body aches, and fatigue. A characteristic circular “target” red rash can mark the site of the tick bite, but isn’t always noticed. In fact, many people don’t realize that they’ve been bitten, and weeks can pass before they see a doctor. By then the infection has spread, sometimes causing additional rashes and/or neurological, cardiac, and rheumatological symptoms that mimic those of other conditions. All of this can make getting the right diagnosis frustrating, especially in areas where Lyme disease is rare.
Even when Lyme disease is suspected early on, the bacterium is unusually slow growing and present at low levels, so it can take a while before blood tests detect antibodies to confirm the condition. By then, knocking out the infection with antibiotics can be more challenging. But research progress continues to be made toward improving the diagnosis of Lyme disease.
An NIH-supported team recently uncovered a unique gene expression pattern in white blood cells from people infected with the Lyme disease-causing bacterium Borrelia burgdorferi [1]. This distinctive early gene signature, which persists after antibiotic treatment, is unique from other viral and bacterial illnesses studies by the team. With further work and validation, the test could one day possibly provide a valuable new tool to help doctors diagnose Lyme disease earlier and help more people get the timely treatment that they need.
