Following DNA Compaction During the Cell Cycle by X-ray Nanodiffraction.
Clément Y J HémonnotChristiane RankeOliva SaldanhaRita GraceffaJohannes HagemannSarah KösterPublished in: ACS nano (2016)
X-ray imaging of intact biological cells is emerging as a complementary method to visible light or electron microscopy. Owing to the high penetration depth and small wavelength of X-rays, it is possible to resolve subcellular structures at a resolution of a few nanometers. Here, we apply scanning X-ray nanodiffraction in combination with time-lapse bright-field microscopy to nuclei of 3T3 fibroblasts and thus relate the observed structures to specific phases in the cell division cycle. We scan the sample at a step size of 250 nm and analyze the individual diffraction patterns according to a generalized Porod's law. Thus, we obtain information on the aggregation state of the nuclear DNA at a real space resolution on the order of the step size and in parallel structural information on the order of few nanometers. We are able to distinguish nucleoli, heterochromatin, and euchromatin in the nuclei and follow the compaction and decompaction during the cell division cycle.
Keyphrases
- electron microscopy
- high resolution
- single molecule
- cell cycle
- single cell
- visible light
- cell therapy
- cell proliferation
- induced apoptosis
- circulating tumor
- computed tomography
- optical coherence tomography
- cell free
- mass spectrometry
- photodynamic therapy
- stem cells
- cell cycle arrest
- signaling pathway
- mesenchymal stem cells
- extracellular matrix
- endoplasmic reticulum stress
- oxidative stress
- magnetic resonance
- bone marrow
- pi k akt
- contrast enhanced