Structome of Saccharomyces cerevisiae determined by freeze-substitution and serial ultrathin-sectioning electron microscopy

• Published in: Journal of electron microscopy Vol. 60; no. 5; p. 321
• Main Authors: Yamaguchi, Masashi, Namiki, Yuichi, Okada, Hitoshi, Mori, Yuko, Furukawa, Hiromitsu, Wang, Jinfang, Ohkusu, Misako, Kawamoto, Susumu
• Format: Journal Article
• Language: English
• Published: Japan 01.10.2011
• Subjects: Cell Nucleus - ultrastructure; Cell Wall - ultrastructure; Cellular Structures - ultrastructure; Endoplasmic Reticulum - ultrastructure; Freeze Substitution - methods; G1 Phase; Golgi Apparatus - ultrastructure; Imaging, Three-Dimensional; Microscopy, Electron, Transmission - methods; Mitochondria - ultrastructure; Saccharomyces cerevisiae - cytology; Saccharomyces cerevisiae - ultrastructure; Vacuoles - ultrastructure
• ISSN: 1477-9986
• DOI: 10.1093/jmicro/dfr052

The cell structure has been studied using light and electron microscopies for centuries, and it is assumed that the whole structure is clarified by now. Little quantitative and three-dimensional analysis of cell structure, however, has been undertaken. We have coined a new word, 'structome', by combining 'structure' and '-ome', and defined it as the 'quantitative and three-dimensional structural information of a whole cell at the electron microscopic level'. In the present study, we performed structome analysis of Saccharomyces cerevisiae, one of the most widely researched biological materials, by using freeze-substitution and serial ultrathin-sectioning electron microscopy. Our analysis revealed that there were one to three mitochondria, ~220 000 ribosomes in a cell, and 13-28 endoplasmic reticula/Golgi apparatus which do not form networks in the cytoplasm in the G1 phase. Nucleus occupied ~10.5% of the cell volume; cell wall occupied ~17%; vacuole occupied ~5.8%; cytoplasm occupied ~64%; and mitochondria occupied only ~1.7% in the G1 phase. Structome analysis of cells would form a base for the post-genome research.