Category: Cells

Twisting and Turning: Unraveling What Causes Asymmetry

0 comments

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.

Asymmetry in our bodies plays an important role in how they work, affecting everything from function of internal systems to the placement and shape of organs. Take a look at your hands. They are mirror images of each other, but they’re not identical. No matter how you rotate them or flip them around, they will never be the same. This is an example of chirality, which is a particular type of asymmetry. Something is chiral if it can’t overlap on its mirror image.

An image of a pair of hands, palms facing up. An arrow points to another image of the left hand on top of the right, both palms still facing up, illustrating that they can’t be superimposed. Our hands are chiral: They’re mirror images but aren’t identical.

Scientists are exploring the role of chirality and other types of asymmetry in early embryonic development. Understanding this relationship during normal development is important for figuring out how it sometimes goes wrong, leading to birth defects and other medical problems.

Continue reading “Twisting and Turning: Unraveling What Causes Asymmetry”

Explore Our Virtual Learning STEM Resources

1 comment

If you’re looking for engaging ways to teach science from home, NIGMS offers a range of resources that can help.

Cover of the graphic novel Occupied by Microbes!, showing four teens racing downhill on skateboards. 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:

  • Apps
  • Interactives
  • Online books
  • Curricula and lesson plans
  • Short movies

Students can learn about sleep, cells, growth, microbes, a healthy lifestyle, genetics, and many other subjects.

Continue reading “Explore Our Virtual Learning STEM Resources”

The Meat of the Matter: Learning How Gut Microbiota Might Reduce Harm from Red Meat

0 comments
Drawing of intestines with a magnifying glass showing bacteria within the intestine.Microbiota in the intestines. Credit: iStock.

Research on how diet impacts the gut microbiota has rapidly expanded in the last several years. Studies show that diets rich in red meat are linked to diseases such as colon cancer and heart disease. In both mice and humans, researchers have recently discovered differences in the gut microbiota of those who eat diets rich in red meat compared with those who don’t. This is likely because of a sugar molecule in the red meat, called N-glycolylneuraminic acid (Neu5Gc), that our bodies can’t break down. Researchers believe the human immune system sees Neu5Gc as foreign. This triggers the immune system, causing inflammation in the body, and possibly leads to disease over time.

Continue reading “The Meat of the Matter: Learning How Gut Microbiota Might Reduce Harm from Red Meat”

Cool Images: A Colorful—and Halloween-Inspired—Collection

0 comments

Transformations aren’t just for people or pets around Halloween. Scientific images also can look different than you might expect, depending on how they’re photographed. Check out these tricky-looking images and learn more about the science behind them.

A human fibroblast cell dividing. A tan-colored area surrounds the cell that contains two magenta-colored centers. Green dots line the area where the cell is dividing. Credit: Nilay Taneja, Vanderbilt University, and Dylan T. Burnette, Ph.D., Vanderbilt University School of Medicine.

Do you have a hunch about what this image is? Perhaps something to do with dry leaves? It’s a human fibroblast cell undergoing cell division, or cytokinesis, into two daughter cells. Cytokinesis is essential for the growth and development of new cells. And fibroblasts play a big role in wound healing by helping with contraction and closure.

Continue reading “Cool Images: A Colorful—and Halloween-Inspired—Collection”

Cilia: Tiny Cell Structures With Mighty Functions

3 comments
Black-and-white video of cilia lining a cell wall and waving back and forth. Credit: Zvonimir Dogic, Brandeis University.

Imagine an army of tiny soldiers stationed throughout your body, lining cells from your brain to every major organ system. Rather than standing at attention, this tiny force sweeps back and forth thousands of times a minute. Their synchronized action helps move debris along the ranks to the nearest opening. Other soldiers stand as sentries, detecting changes in your environment, relaying that information to your brain, and boosting your senses of taste, smell, sight, and hearing.

Your brain may be the commander in chief, but these rank-and-file soldiers are made up of microscopic cell structures called cilia (cilium in singular).

Here we describe these tiny but mighty cell structures in action.

Continue reading “Cilia: Tiny Cell Structures With Mighty Functions”

Five Fabulous Fats

2 comments

Happy Fat Tuesday!

On this day, celebrated in many countries with lavish parties and high-fat foods, we’re recognizing the importance of fats in the body.

You’ve probably heard about different types of fat, such as saturated, trans, monounsaturated, omega-3, and omega-6. But fats aren’t just ingredients in food. Along with similar molecules, they fall under the broad term lipids and serve critical roles in the body. Lipids protect your vital organs. They help cells communicate. They launch chemical reactions needed for growth, immune function, and reproduction. They serve as the building blocks of your sex hormones (estrogen and testosterone).

Here we feature five of the hundreds of lipids that are essential to health.

Continue reading “Five Fabulous Fats”

Interview With a Scientist—Elhanan Borenstein: Metagenomics Systems Biology

0 comments


Cataloging the human microbiome—the complete collection of bacteria, fungi, archaea, protists, and viruses that live in and on our bodies—is an enormous task. Most estimates put the number of organisms who call us home on par with the number of our own cells. Imagine trying to figure out how the billions of critters influence each other and, ultimately, impact our health. Elhanan Borenstein,Link to external web site a computer scientist-cum-genomicist at the University of Washington, and his team are not only tackling this difficult challenge, they are also trying to obtain a systems-level understanding of the collective effect of all of the genes, proteins, and metabolites produced by the numerous species within the microbiome.

Continue reading “Interview With a Scientist—Elhanan Borenstein: Metagenomics Systems Biology”

Molecular Fireworks: How Microtubules Form Inside Cells

1 comment
A video depicting red strands of various lengths exploding outward from a focal point at the left. The strands are tipped in neon green.
       Microtubules sprout from one another. Credit: Petry lab, Princeton University.

The red spray pictured here may look like fireworks erupting across the night sky on July 4th, but it’s actually a rare glimpse of tiny protein strands called microtubules sprouting and growing from one another in a lab. Microtubules are the largest of the molecules that form a cell’s skeleton. When a cell divides, microtubules help ensure that each daughter cell has a complete set of genetic information from the parent. They also help organize the cell’s interior and even act as miniature highways for certain proteins to travel along.

As their name suggests, microtubules are hollow tubes made of building blocks called tubulins. Scientists know that a protein called XMAP215 adds tubulin proteins to the ends of microtubules to make them grow, but until recently, the way that a new microtubule starts forming remained a mystery.

Sabine Petry Link to external web site and her colleagues at Princeton University developed a new imaging method for watching microtubules as they develop and found an important clue to the mystery. They adapted a technique called total internal reflection fluorescence (TIRF) microscopy, which lit up only a tiny sliver of a sample from frog egg (Xenopus) tissue. This allowed the scientists to focus clearly on a few of the thousands of microtubules in a normal cell. They could then see what happened when they added certain proteins to the sample.

Continue reading “Molecular Fireworks: How Microtubules Form Inside Cells”

Interview With a Scientist: Andrew Goodman, Separating Causation and Correlation in the Microbiome

0 comments

You’ve likely heard some variation of the statistic that there are at least as many microbial cells in our body as human cells. You may have also heard that the microscopic bugs that live in our guts, on our skins, and every crevice they can find, collectively referred to as the human microbiome, are implicated in human health. But do these bacteria, fungi, archaea, protists, and viruses cause disease, or are the specific populations of microbes inside us a result of our state of health? That’s the question that drives the research in the lab of Andrew Goodman Link to external web site, associate professor of microbial pathogenesis at Yale University.

Continue reading “Interview With a Scientist: Andrew Goodman, Separating Causation and Correlation in the Microbiome”