Friday, December 10, 2010
Molecular topography of a cell can be successfully monitored by combining powerful imaging techniques such as electron microscopy and fluorescence nanoscopy ( STED or PALM). Recently, Prof. Erik M Jorgensen and his colleagues described a correlative fluorescence electron microscopy technique to localize protein on specific organelles. Here organelles first are revealed by electron microscopy and proteins are monitored by fluorescence imaging. As a result of image correlation between these two imaging modalities, proteins can be localized with nanometer accuracy. The paper also demonstrates localization of histone proteins on mitochondria.
Here is the paper that was published in Nature Methods: "Protein localization in electron micrographs using fluorescence nanoscopy"
Partially coherent object illumination allowed researchers to reconstruct the three-dimensional ultrastructures of cells such as the double nuclear membrane, nuclear pores, nuclear membrane channels, mitochondrial cristae and lysosomal inclusions. These results demonstrated visualization of structures at ~36-nm (Rayleigh) and ~70-nm (Fourier ring correlation) resolution.
Here is the paper that was reported in Nature Methods Journal: "Three-dimensional cellular ultrastructure resolved by X-ray microscopy"