Bill Bement describes himself as a guy who “passionately, obsessively, and almost feverishly” loves to study cells. His excitement comes through in our final installment of the American Society for Cell Biology’s Celldance 2014. Bement, an NIH grantee at the University of Wisconsin, Madison, shares his scanning confocal microscope with us for this fascinating glimpse into the rapid response of cells to repair holes, tears, and other structural damage in their protective outer membranes.
For most people, this damage response runs on biochemical autopilot, sealing any membrane break within seconds to keep the cell viable and healthy. But some people inherit gene mutations that make sealing and patching difficult, particularly in cells that operate under repetitive mechanical stress. For example, some forms of muscular dystrophy stem specifically from an inherited inability to repair breaks in the cell membrane of skeletal muscle cells. In one type of disease that affects both skeletal and cardiac muscle, a gene mutation alters the shape of a protein called dysferlin, which normally binds annexin proteins that, as noted in the video, play a vital role in patching holes. In the presence of a glitch in dysferlin, the rapid chain of biochemical events needed to enable such repair breaks down.
There’s still an enormous amount to learn about cell membrane repair, so it will be interesting to see what Bement’s microscope and camera will show us next.
Bement Lab, University of Wisconsin-Madison
Celldance 2014, American Society for Cell Biology
NIH Support: National Institute of General Medical Sciences
We humans have long wondered how, exactly, we develop from embryos into adults. This photo of an embryonic smooth muscle cell hints at the tremendous complexity of this fundamental biological mystery. And for those of you who might be wondering just what smooth muscles are, they’re the involuntary muscles found in places like the walls of our blood vessels, the digestive tract, the bladder, and the respiratory system.
This exquisite photo was produced using laser scanning confocal microscopy — a precise imaging method that includes the dimension of depth for scientific analysis. Here, green is used to label thin filaments of the protein actin, which is a key component of the cell’s cytoskeleton, and blue indicates another protein, called vinculin, which is enriched in locations involved in cell-cell adhesion.
Slowly but surely, using all the technology and tools available to us, we are unraveling the mysteries of biology — and turning our discoveries into health.
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Certainly – as you can see here – stem cells are spectacularly beautiful. But they also hold spectacular promise for medicine. That’s why I immediately expressed my enthusiasm for Monday’s Supreme Court ruling that effectively enables NIH to continue conducting and funding responsible, scientifically worthy stem cell research.
There are many kinds of stem cells. This is a picture of induced pluripotent stem cells – or, iPS cells. Investigators have recently begun using iPS cells to model several neurological diseases – including Parkinson’s. The cells here have been treated with growth factors that coax them into becoming the dopamine producing (dopaminergic) neurons lost in Parkinson’s. The colorized markers indicate the presence of three proteins found within dopaminergic neurons: (1) the enzyme needed to produce dopamine (tyrosine hydroxylase, in blue), (2) a structural protein specific to neurons (Type III beta-tubulin, in green), and (3) a gene regulatory protein needed in dopaminergic neurons (FOXA2, in red). The color-mixing in some cells indicates that all three proteins are present – confirming that these cells are on their way to becoming dopaminergic neurons.
Today’s image is more than just a pretty picture. It’s a window into the ways that disease affects the body – and possibly the ways we might counter those affects. The NIH/NINDS web site has more information about how iPS cells are being used to study Parkinson’s and other neurological disorders.
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This stunning picture of a human bone cancer cell won artistic accolades: 3rd place in the Nikon Small World Competition. DNA, the blueprint of life, is actually blue in this photo. The yellow squiggles are little powerhouses called mitochondria that generate ATP ‘fuel’ for the cell. The purple wisps are filaments of actin, which help the cell move, keep its shape, and traffic chemicals from one part of the cell to another.
Happy New Year everyone.
Posted In: Science