Cool Videos: Making Multicolored Waves in Cell Biology

Bacteria are single-cell organisms that reproduce by dividing in half. Proteins within these cells organize themselves in a number of fascinating ways during this process, including a recently discovered mechanism that makes the mesmerizing pattern of waves, or oscillations, you see in this video. Produced when the protein MinE chases the protein MinD from one end of the cell to the other, such oscillations are thought to center the cell’s division machinery so that its two new “daughter cells” will be the same size.

To study these dynamic patterns in greater detail, Anthony Vecchiarelli purified MinD and MinE proteins from the bacterium Escherichia coli. Vecchiarelli, who at the time was a postdoc in Kiyoshi Mizuuchi’s intramural lab at NIH’s National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), labeled the proteins with fluorescent markers and placed them on a synthetic membrane, where their movements were then visualized by total internal reflection fluorescence microscopy. The proteins self-organized and generated dynamic spirals of waves: MinD (blue, left); MinE (red, right); and both MinD and MinE (purple, center) [1].

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Snapshots of Life: Coming Face to Face with Development

Zebrafish larva

Credit: Oscar Ruiz and George Eisenhoffer, University of Texas MD Anderson Cancer Center, Houston

Zebrafish (Danio rerio) is a favorite model for studying development, in part because its transparent embryos make it possible to produce an ever-growing array of amazingly informative images. For one recent example, check out this Federation of American Societies for Experimental Biology’s 2016 BioArt winner, which shows the developing face of a 6-day-old zebrafish larva.

Yes, those downturned “lips” are indeed cells that will go on to become the fish’s mouth. But all is not quite what it appears: the two dark circles that look like eyes are actually developing nostrils. Both the nostrils and mouth express high levels of F-actin (green), a structural protein that helps orchestrate cell movement. Meanwhile, the two bulging areas on either side of the fish’s head, which are destined to become eyes and skin, express keratin (red).

Oscar Ruiz, who works in the lab of George Eisenhoffer at The University of Texas MD Anderson Cancer Center, Houston, used a confocal microscope to create this image. What was most innovative about his work was not the microscope itself, but how he prepared the sample for imaging. With traditional methods, researchers can only image the faces of zebrafish larvae from the side or the bottom. However, the Eisenhoffer lab has devised a new method of preparing fish larvae that makes it possible to image their faces head-on. This has enabled the team to visualize facial development at much higher resolution than was previously possible.

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Talking Music and Science with Yo-Yo Ma

It’s not every day that an amateur guitar picker gets to play a duet with an internationally renowned classical cellist. But that was my thrill this week as I joined Yo-Yo Ma in a creative interpretation of the traditional song, “How Can I Keep from Singing?” Our short jam session capped off Mr. Ma’s appearance as this year’s J. Edward Rall Cultural Lecture.

The event, which counts The Dalai Lama, Maya Angelou, and Atul Gawande among its distinguished alumni, this year took the form of a conversation on the intersection of music and science—and earned a standing ovation from a packed house of researchers, patients, and staff here on the National Institutes of Health (NIH) campus in Bethesda, MD.

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Too Old For Building Blocks? Not These.

Cover of Science magazine, displaying a set of colorful building blocks.

Cover of Science, November 30, 2012.

This looks like the type of Lego kit I would get my grandkids for Christmas, or a new version of Tetris. It is, in fact, much cooler. These are ‘DNA bricks’—short strands of DNA that plug into each other like a peg in a hole. I’m excited to tell you that the scientists at the Wyss Institute in Boston, MA, who developed this technology were recipients of the NIH Director’s New Innovator Award, which encourages out of the box thinking specifically for young researchers. So what can you do with these bricks? Build microscopic 3-D structures. In some cases, if the recipe of DNA bricks is just right the set of bricks can self-assemble. In fact the scientists have already created 100 different self-assembling structures (like the ones pictured above on the cover of the November 30th issue of Science). These structures could be used for designing intricate labyrinths for everything from biomedicine to nanotechnology. Very, very exciting stuff.

Check out these quick flicks to see the range of structures up close; the second one looks like a collection of rainbow worms attacking each other.

Building 3D Structures with DNA Bricks

DNA Bricks – Molecular Animation