Quantitative 3D imaging of yeast by hard X‐ray tomography

Abstract

Full-field hard X-ray tomography could be used to obtain three-dimensional (3D) nanoscale structures of biological samples. The image of the fission yeast, Schizosaccharomyces pombe, was clearly visualized based on Zernike phase contrast imaging technique and heavy metal staining method at a spatial resolution better than 50 nm at the energy of 8 keV. The distributions and shapes of the organelles during the cell cycle were clearly visualized and two types of organelle were distinguished. The results for cells during various phases were compared and the ratios of organelle volume to cell volume can be analyzed quantitatively. It showed that the ratios remained constant between growth and division phase and increased strongly in stationary phase, following the shape and size of two types of organelles changes. Our results demonstrated that hard X-ray microscopy was a complementary method for imaging and revealing structural information for biological samples.

3D imaging of a rice pollen grain using transmission X-ray microscopy

“…In this contribution, we present 3D tomography of rice pollen grains using hard X-ray nano-tomography. Zernike phase contrast and heavy metal staining (Zheng et al, 2012;Wang et al, 2014) have been utilized to achieve high-quality tomography. The reconstructions clearly reveal subcellular structures within an intact cell.…”

Quantitative imaging of Candida utilis and its organelles by soft X‐ray Nano‐CT

“…As shown in Figure , the volume ratio of the vacuoles was much larger than any other organelles and was much smaller, from 40.08% for the cell in the G1 phase to 13.47% for the cell in the budding phase. A similar trend was shown in some investigations (Zheng et al ., ). The volume ratio of vacuoles constitutes the majority of the volume ratio of organelles.…”

Imaging cell morphology and physiology using X-rays

“…In both categories of microscope soft and hard x-rays can be used, depending on the desired penetration depth, spatial resolution and contrast mechanism [54]. While there are multiple examples of using soft x-ray coherent diffraction imaging [55–61] and hard x-ray microscopy for visualizing cells [62–64] these techniques are mostly proof-of-principal studies and are not yet allowing the type of systematic studies required in cell biology. The preferred method for morphological studies of single cells is transmission soft x-ray microscopy.…”

“…Therefore, yeast has become a widely used model organism to study cell growth and division [107]. Yeast has been studied extensively using soft X-ray microscopy [62, 76, 77, 108–110]. Based on other methods, it was already established that ploidy (the number of complete sets of chromosomes) in yeast has a direct and linear proportionality on cell size.…”