Your immune system is on patrol every day. It protects your body from bacteria, viruses, and other germs. But if something goes wrong, it can also cause big problems.
Sepsis happens when your body’s response to an infection spirals out of control. Your body releases molecules into the blood called cytokines to fight the infection. But those molecules then trigger a chain reaction.
“Sepsis is basically a life-threatening infection that leads to organ dysfunction,” says Richard Hotchkiss, M.D., who studies sepsis at Washington University in St. Louis, Missouri. The most dangerous stage of sepsis is called septic shock. It can cause multiple organs to fail, including the liver, lungs, and kidneys.
Septic shock begins when the body’s response to an infection damages blood vessels. When blood vessels are damaged, your blood pressure can drop very low. Without normal blood flow, your body can’t get enough oxygen.
Your body is made up of trillions of cells that all originate from just one—a fertilized egg. The massive multiplication of cells after conception is possible thanks to cell division, which occurs when one cell splits into two. Cell division not only enables growth but also replaces damaged or dead cells and makes reproduction possible. There are two kinds of cell division: mitosis and meiosis.
Mitosis is shown on the left, and meiosis is shown on the right. Credit: Judith Stoffer. Click to enlarge
Dr. Ramos-Benítez researches interactions between pathogens—such as the viruses that cause Ebola and COVID-19—and their hosts. He’s also the founder and president of Ciencia en tus Manos (“Science in Your Hands”), a nonprofit organization that presents scientific information in Spanish and aims to provide a community to support the next generation of scientists.
Navajo students are contributing to public health efforts in diabetes, COVID-19, domestic violence, and maternal and child health through the Navajo Native American Research Center for Health (NARCH) Partnership. “Our goal is to really enhance the educational pathways available to Navajo students from high school to graduate school and beyond,” says Mark Bauer, Ph.D., a co-director of the Navajo NARCH Partnership and professor at Diné College—a tribal college on the Navajo Nation. (Diné means “the people” and is how Navajo people refer to themselves in their native language.)
Most cells are naturally colorless, which is why scientists often use fluorescent tags and other tools to color cell structures and make them easier to study. (Check out the Pathways imaging issue for more on scientific imaging techniques). Here, we’re showcasing cell images that feature shades of blue. Visit our Image and Video Gallery for additional images of cells in all the colors of the rainbow, as well as other scientific photos, illustrations, and videos.
“You’re not going to be able to do biology without understanding programming in the future,” Melissa Wilson, Ph.D., an associate professor of genomics, evolution, and bioinformatics at Arizona State University, said in her 2019 NIGMS Early Career Investigator Lecture. “You don’t have to be an expert programmer. But without understanding programming, I can assert you won’t be able to do biology in the next 20 years.”
A growing number of researchers, like Dr. Wilson, are studying biology using computers and mathematical methods. Some of them started in traditional biology or other life science labs, while others studied computer science or math first. Here, we’re featuring two researchers who took different paths to computational biology.
In everyday use, most people understand translation to mean converting words from one language to another. But when biologists talk about translation, they mean the process of making proteins based on the genetic information encoded in messenger RNA (mRNA). Proteins are essential for virtually every process in our bodies, from transporting oxygen to defending against infection, so translation is vital for keeping us alive and healthy.
Apoptosis is the process by which cells in the body die in a controlled and predictable way because they have DNA damage or are no longer needed. The term comes from a Greek word meaning “falling off,” as in leaves falling from a tree.
When a cell undergoes apoptosis, it shrinks and pulls away from its neighbors. As the cytoskeleton that gives it shape and structure collapses, the envelope around the cell’s nucleus breaks down, and its DNA breaks into pieces. Its surface changes, signaling its death to other cells and leading a healthy cell to engulf the dying one and recycle its components.
What looks like a bubbling lava lamp is actually part of an egg cell’s maturation process. In many animals, the egg cell develops alongside sister cells. These sister cells are called nurse cells in the fruit fly (Drosophila melanogaster), and their job is to “nurse” an immature egg cell, or oocyte. Toward the end of oocyte development, the nurse cells transfer all their contents into the oocyte in a process called nurse cell dumping. This video captures this transfer, showing significant shape changes on the part of the nurse cells (blue), which are powered by wavelike activity of the protein myosin (red).
Proteins (such as hemoglobin, actin, and amylase) are workhorse molecules that contribute to virtually every activity in the body. Some of proteins’ many jobs include carrying oxygen from your lungs to the rest of your body (hemoglobin), allowing your muscles to move (actin and myosin), and digesting your food (amylase, pepsin, and lactase). All proteins are made up of chains of amino acids that fold into specific 3D structures, and each protein’s structure allows it to perform its distinct job. Proteins that are misfolded or misshapen can cause diseases such as Parkinson’s or cataracts.
While it’s straightforward to use the genetic code to predict amino acid sequences of proteins from gene sequences, the vast diversity of protein shapes and many factors that influence a protein’s 3D structure make it much more complicated to create simple folding rules that could be used to predict proteins’ structures from these sequences. Scientists have worked on this problem for nearly 50 years, and NIGMS has supported many of their efforts, including the Critical Assessment of Structure Prediction (CASP) program.