Note to our Biomedical Beat readers: Echoing the sentiments NIH Director Francis Collins made on his blog, NIGMS is making every effort during the COVID-19 pandemic to keep supporting the best and most powerful science. In that spirit, we’ll continue to bring you stories across a wide range of NIGMS topics. We hope these posts offer a respite from the coronavirus news when needed.
Mitosis is fundamental among all organisms for reproduction, growth, and cell replacement. When a cell divides, it’s vital that the two new daughter cells maintain the same genes as the parent.
In one step of mitosis, chromosomes are segregated into two groups, which will go into the two new daughter cells. But if the chromosomes don’t divide properly, one daughter cell may have too many and the other too few. Having the wrong number of chromosomes, a condition called aneuploidy, can trigger cells to grow out of control.
An illustration of chromosomes being segregated equally and unequally during mitosis. Credit: Deluca Lab, Colorado State University.
How chromosome segregation errors disrupt cell division is an important area of research. Although it’s been studied for decades, new aspects are still being uncovered and much remains unknown. NIGMS-funded scientists are studying different aspects of mitosis and chromosome segregation. Understanding the details can provide vital insight into an essential biological process and may also be the key to developing better drugs for cancer and other diseases.
If you’re looking for engaging ways to teach science from home, NIGMS offers a range of resources that can help.
A SEPA-funded resource about microbes. Credit: University of Nebraska, Lincoln.
Our Science Education and Partnership Award (SEPA) webpage features free, easy-to-access STEM and informal science education projects for pre-K through grade 12. Aligned with state and national standards for STEM teaching and learning, the program has tools such as:
Curricula and lesson plans
Students can learn about sleep, cells, growth, microbes, a healthy lifestyle, genetics, and many other subjects.
Sohini Ramachandran, Brown University. Credit: Danish Saroee/Swedish Collegium for Advanced Study.
Recent advances in computing enable researchers to explore the life sciences in ways that would have been impossible a few decades ago. One new tool is the ability to sequence genomes, revealing people’s full DNA blueprints. The collection of more and more genetic data allows researchers to compare the DNA of many people and observe variations, including those shared by people with a common ancestry.
Sohini Ramachandran , Ph.D., is director of the Center for Computational Molecular Biology and associate professor of biology and computer science at Brown University in Providence, Rhode Island. She is also a recent recipient of the Presidential Early Career Award for Scientists and Engineers (PECASE). Dr. Ramachandran researches the causes and consequences of human genetic variations using computer models. Starting with genomic data from living people, her lab applies statistical methods, mathematical modeling, and computer simulations to discover how human populations moved and changed genetically over time.
Regeneration is the natural process of replacing or restoring cells that have been lost or damaged due to injury or disease. A few animals can regrow entire organs or other body parts, but most have limited abilities to regenerate.
in the field of regenerative medicine study how some animals are able to
rebuild lost body parts. By better understanding these processes and learning
how to control them, researchers hope to develop new methods to treat injuries
and diseases in people.
Take this quiz to test what you know about regeneration and regenerative medicine. Then check out our Regeneration fact sheet and the regeneration issue of Pathways, a teaching resource produced in collaboration with Scholastic.
Over the past 12 months, we’ve explored a variety of topics in genetics, cell biology, chemistry, and careers in the biomedical sciences. As we ring in the new year, we bring you our top three posts of 2019. If your favorite is missing, let us know what it is in the comments section below!
Hawaiian bobtail squid. Credit: Dr. Satoshi Shibata.
Studying research organisms, such as those featured in this post, teaches us about ourselves. These amazing creatures, which have some traits similar to our own, may hold the key to preventing and treating an array of complex diseases.
Most of what we know comes from intensive study of research organisms—mice, fruit flies, worms, zebrafish, and a few others. But according to Alejandro Sánchez Alvarado , a researcher at the Stowers Institute for Medical Research in Kansas City and a Howard Hughes Medical Institute Investigator, these research organisms represent only a tiny fraction of all animal species on the planet. Under-studied organisms could reveal important biological phenomena that simply don’t occur in the handful of models typically studied, he says.
DNA, with its double-helix shape, is the stuff of genes. But genes themselves are only “recipes” for protein molecules, which are molecules that do the real heavy lifting (or do much of the work) inside cells.
Artist interpretation of RNAP grasping and unwinding a DNA double helix. Credit: Wei Lin and Richard H. Ebright.
Here’s how it works. A molecular machine called RNA polymerase (RNAP) travels along DNA to find a place where a gene begins. RNAP uses a crab-claw-like structure to grasp and unwind the DNA double helix at that spot. RNAP then copies (“transcribes”) the gene into messenger RNA (mRNA), a molecule similar to DNA.
The mRNA molecule travels to one of the cell’s many protein-making factories (ribosomes), which use the mRNA message as instructions for making a specific protein.
Dr. Melissa Wilson.
Credit: Chia-Chi Charlie Chang.
The X and Y chromosomes, also known as sex chromosomes, differ greatly from each other. But in two regions, they are practically identical, said Melissa Wilson , assistant professor of genomics, evolution, and bioinformatics at Arizona State University.
What do you have in common with rodents, birds, and reptiles? A lot more than you might think. These creatures have organs and body systems very similar to our own: a skeleton, digestive tract, brain, nervous system, heart, network of blood vessels, and more. Even so-called “simple” organisms such as insects and worms use essentially the same genetic and molecular pathways we do. Studying these organisms provides a deeper understanding of human biology in health and disease, and makes possible new ways to prevent, diagnose, and treat a wide range of conditions.
Historically, scientists have relied on a few key organisms, including bacteria, fruit flies, rats, and mice, to study the basic life processes that run bodily functions. In recent years, scientists have begun to add other organisms to their toolkits. Many of these newer research organisms are particularly well suited for a specific type of investigation. For example, the small, freshwater zebrafish grows quickly and has transparent embryos and see-through eggs, making it ideal for examining how organs develop. Organisms such as flatworms, salamanders, and sea urchins can regrow whole limbs, suggesting they hold clues about how to improve wound healing and tissue regeneration in humans.
Women have two X chromosomes (XX) and men have one X and one Y (XY), right? Not always, as you’ll learn from the quiz below. Men can be XX and women can be XY. And many other combinations of X and Y are possible.