When X-ray crystallography was developed decades ago, it allowed scientists to discern proteins inside cells. But to do that, they had to isolate those proteins and turn them into crystals to see them. Then came cryo-electron microscopy, which also required separating biomolecules from their surroundings. But now we have cryo-electron tomography (cryo-ET), which not only boosts the resolution of what scientists look at, but they can see proteins and biomolecules in three dimensions as they exist inside cells. Cryo-ET involves freezing and slicing a cell into unimaginably thin slices, imaging each slice with an electron microscope, and then assembling the images into a 3-dimensional visualization.
Examining proteins at this level is crucial in understanding how some diseases work. Cryo-ET is already being used to study the protein action in ALS, Huntington’s, and Parkinson’s disease. In the future, it can be used to study the effect of medication or other treatments in those proteins at the cellular level. Read more about this astounding imaging technique at Nature. -via Damn Interesting
(Image credit: S. Albert et al./PNAS/CC BY 4.0)
Algal cell under cryo-ET shows the endoplasmic reticulum (in yellow), the pouches of the Golgi apparatus (green and magenta) and the vesicles (small circles of various colors). Image: Y. S. Bykkov et al./eLIFE (CC BY 4.0)
Image: Nature
Whole cell sliced thinly and imaged by microscopy. Image: Janelia Research Campus HHMI