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This post was contributed by guest blogger, Eugenia Rojas.

A question worthy of a PhD: How do you visualize protein turnover within a neuron?

For my PhD I studied a synaptic protein that is linked to neurodegeneration. The level of this protein is decreased in Alzheimer’s disease patient’s brains. However, it is not known why or how this happens. Therefore, I set out to study how protein turnover is regulated in neurons.

This post was contributed by Doug Richardson, Director of the Harvard Center for Biological Imaging and a Lecturer on Molecular and Cellular Biology at Harvard University.

No matter whether you are a sports photographer at the Super Bowl, a medical technologist taking an x-ray, or a biologist imaging the smallest structures of life; the key to a great image is contrast. The human visual system relies primarily on contrast to identify individual objects and perceive the world around us. Without contrast, objects simply vanish into noise.

This post was contributed by guest blogger, Luke Lavis, a Group Leader at the Janelia Research Campus, Howard Hughes Medical Institute.

Chemistry is dead, long live chemistry!

The discovery of green fluorescent protein (GFP) sparked a renaissance in biological imaging. Suddenly, cell biologists were no longer beholden to chemists and (expensive) synthetic fluorophores. Add a dash of DNA with an electrical jolt and cells become perfectly capable of synthesizing fluorophore fusions on their own. Subsequent advances in fluorescent proteins have replicated many of the properties once exclusive to small-molecules: red-shifted spectra, ion sensitivity, photoactivation, etc. These impressive advances lead to an obvious question: In this age of GFP and its ilk, why should cell biologists talk to chemists?

This post was contributed by Kurt Thorn of the Nikon Imaging Center at UCSF.

A common requirement for live cell imaging experiments is the ability to follow multiple fluorescently tagged species simultaneously. To do so with fluorescent protein labels requires multiple fluorescent proteins whose excitation and emission spectra differ sufficiently for them to be imaged in distinct fluorescent channels on the microscope. With the proliferation of fluorescent proteins in recent years, there are many fluorescent protein combinations that can be imaged together, but this also means that the choice of fluorescent proteins requires some thought.

If you start poking around on Addgene’s Fluorescent Protein Guide to In Vivo Imaging, you’ll pretty quickly notice the name Vladislav Verkhusha popping up again and again, and for good reason.

We all know scientists have used fluorescent proteins to observe what’s happening inside cells for at least a couple of decades. Green is the classic color, but fluorescent proteins are available in a variety of hues. While those tools are great for many applications, Verkhusha and his lab at Albert Einstein College of Medicine in New York recognized their limitations for peering right through living animals to see their organs – a liver or brain, say, or maybe a tumor. They wanted to find something better.