The non-profit organization, IIRS, conducted in 2007 a research project entitled "A study on the present condition and future prospects of visualization technology in the life sciences" with a grant-in-aid from the Watanabe Memorial Foundation for the Advancement of Technologies. The study clearly showed that there is great disparity in scientific environments in Japan. As a result, a large number of scientists are having difficulty getting access to ultrastructural research apparatus. In order to promote ultrastructural research in Japan, IIRS is establishing a network system for the joint use of ultrastructural research instruments. This symposium is jointly organized by IIRS and the Japanese Society of Plant Morphology in an effort to discuss the establishment of a functional and effective network system.

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The function of the living matter is based on its structure and materials. The requirements for good structural information are as follows. 1. It represents the structure that closely resembles the living state. 2. High spatial and temporal resolutions. 3. It contains information about the material and its dynamics. 4. Quantitativeness. The light microscope is profitable for the first requirement, and the electron microscope surpasses for the second requirement, i.e., high spatial resolution. In vivo observation of the living matter at high spatial resolution has been an unattainable ambition for biologists of our generation. Now, the first and second requirements seem to have found the solution by the amazing recent developments of the optical systems and imaging techniques. In addition, the molecular structure and dynamics of important bio-molecules, such as various channels and receptors, are clarified at sub-nanometer resolution utilizing the ultra cryo electron microscope tomography. The remarkable advances of molecular biology has cut a pass to the third and fourth requirements. Since 1948 I have devoted my career as an anatomist to the progress of biological imaging and have tried to clarify the relation between the structure and the function of the living matter with the aid of a variety of microscopes as described above.

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In the local university, instruments of electron microscope are usually standard and techniques for electron microscopy are basic. However various experiences of fixation methods for a variety of specimen are accumulated. Therefore the university can contribute the network through supply these information to a local area. Workshops or seminars held by the university and supported by IIRS will be effective in a rise of user of electron microscopy in the area. Support by IIRS of the construct of database how to handle and fix various specimens is also necessary.

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Electron Microscope Laboratory in Riken CDB has been providing support activities on electron microscopy (EM) while original researches have been also performed. The activities include maintenance of equipments such as electron microscopes, consultation about EM analysis and procedures ranging from sample fixation to image recording. We also train researchers' skills of electron microscopy. Clients are both inside and outside CDB. We contact clients during our EM analysis quickly and frequently using email with attached files of images taken with CCD camera. Samples include model animals such as C. elegans, drosophila, mouse or tissue culture cells. Although support activities like ours appear to become increasingly important for analysis of knockout mice or differentiated cells from ES or iPS cells, we still have no promising way to bring up human resources for EM analysis.

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Australian Microscopy & Microanalysis Research Facility (AMMRF) was established in 2007 under the Commonwealth Government's National Collaborative Research Infrastructure Strategy (NCRIS), and is a joint venture between Australian university-based microscopy and microanalysis centers. AMMRF offers light microscopy, electron microscopy and microanalysis equipments accessible to all Australian researchers of biological and material science.

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Cardiolipin (CL) is widely distributed in various prokaryotes and eukaryotes as a membrane phospholipid. CL has a dimeric sturucture and the phosphate groups of CL are negatively charged at neutral pH, thus, CL is classified as an anionic phospholipid. In eukaryotes, it is localized in the inner membrane and at sites of contact between the inner and outer membranes of mitochondria. Biochemical and molecular genetical studies have suggested that CL is involved in many processes and phenomena, such as stabilization of respiratory complex, apotosis, osmotic regulation, mitochondrial morphogenesis. However, the crucial role of CL has not been clarified. The recent identification of genes for enzymes that are required for the biosynthesis of CL in many organisms, as well as the subsequent generation of mutants defective in the biosynthesis of CL has provided molecular tools to dissect the functions of CL. In this review, we summarize the findings obtained by recent studies on the function of CL in prokaryotes and eukaryotes, and discuss the crucial role played by CL.

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In plant chloroplasts and cyanobacteria, glycerolipids that carry galactose in their head group are the predominant lipid components of the membranes whereas mostly phospholipids are the most abundant polar lipid class in the membranes of other organisms. Because of their abundance in the photosynthetic membranes, the importance of these galactolipids in photosynthesis has been suggested. Since the enzymes that catalyze the syntheses of these galactolipids were identified, significant progress has been achieved in the elucidation and understanding of the biosynthetic pathways and their regulatory mechanisms. In addition, genetic and reverse-genetic approaches in these enzymes revealed physiological roles of galactolipids in photosynthesis and adaptation systems to several stresses. In photosynthetic tissues, galactolipids are indispensable for thylakoid membrane biogenesis and are directly involved in the photosynthetic reactions. Moreover, galactolipids are required for membrane maintenance during phosphate deficiency by substituting phospholipids in plastidic and extraplastidic membranes. The regulatory mechanisms for galactolipid biosyntheses upon photomorphogenesis and stress conditions have also been studied in transcription levels and enzymatic activity levels.

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Peroxisomes in higher plant cells are known to differentiate in function depending on the cell type and environmental condition. This remarkable feature of plant peroxisomes is not found in other organisms. In the last decade, significant progress has been made in the study of plant peroxisomal function and its regulation. These studies illustrated that plant peroxisomes have more diverse functions than we previously though, and allowed to identify many genes involving peroxisomal protein targeting and peroxisome biogenesis. We describe recent achievement on the study of peroxisomal function and its regulation in plant cells.

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Higher plants produce a wide variety of isoprenoids via characteristic biosynthesis pathways. Although it has been considered that higher plants may have unique regulatory mechanisms over multiple organelles for isoprenoid biosynthesis, the whole of the regulatory mechanisms remains to be solved. We describe recent achievements on the regulatory mechanisms of the upstream of the isoprenoid biosyntesis in higher plants.

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Male gametophyte in higher plants contains characteristic lipid-rich organelles. Much of the pollen coat material derives from two tapetal lipid-rich organelles: tapetosome and elaioplast. The analysis of lipid components of tapetosome, elaioplast, male gametophyte and pollen coat revealed that they packages a defined series of lipid components. Recently, it is becoming clear that the lipids are critical on the male gametophyte development by reverse-genetic strategy using Arabidopsis. We describe here recent achievements on the role of lipids on the male gametophyte and tapetum development.

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In this review, the history of researches on the plant Golgi apparatus and a part of the author's studies on Golgi apparatus using unicellular green algae and its reproduction during mitosis are presented. In plant cells, Golgi bodies (a stack consisting with 5-15 flat cisternae with 1-3μm in diameter) are distributed over the cytoplasm. They drastically change in structures and enzyme activities during cell cycle. The architecture, the distribution pattern in cells and the reproduction manner of Gogli apparatus are quite different between animal (mammalian) and plant cells. In mammalian cells, many stacks link together and form a single large complex, which is usually located near the cell nucleus. It disassembles at the onset of mitosis. In contrast, in plant cells, Golgi bodies divide into two before prophase of mitosis and do not fragment during mitosis. Our research data show that this difference is not related to cell wall formation, occurred only in plant cells, nor architecture of Golgi apparatus.

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A dioecious plant, Silene latifolia, has heteromorphic XY-type sex chromosomes. Because the sex chromosomes of this species are largest of the karyotype, its structural analysis using fluorescent in situ hybridization (FISH) is easy to be performed. Sex chromosomes are thought to be derived from a pair of autosomes that have been progressively differentiated by the suppression of recombination around locus controlling sex determination, and thereafter unrecombining regions have developed with sex determination genes. On the other hand, a recombining region called pseudoautosomal regions (PAR) is needed to uniformly divide the sex chromosomes in meiosis. We determined the positions of the pseudoautosomal regions (PAR) of the sex chromosomes by the detailed characterization of repetitive sequences on chromosomal ends. Another interesting phenomenon in S. latifolia is that infection of a smut fungus (Microbotryum violaceum) induces the stamen elongation in the female flower, resulting in producing the hermaphroditic flowers. Analysis of the infected females as counter parts of the males may improve our knowledge of the stamen promoting function (SPF) of the Y chromosome. Thus we performed the expression analyses of genes related to stamen elongation in the smut-infected female plant.

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In angiosperms, leaves generally develop as a bifacial structure with distinct adaxial and abaxial identities. The juxtaposition between adaxial and abaxial identities promotes the lateral outgrowth of the leaf blade, leading to the dorsoventrally flattened structure. In monocots, however, unusual leaf type called unifacial leaf is found in a number of divergent taxa. In unifacial leaves, the leaf blade has only the abaxial identity. Unifacial leaves could be an unique material to study the leaf axes formation in monocots, because leaf polarities in unifacial leaves are distinct from those in bifacial leaves. In addition, the mechanism of repeated evolution of such drastic changes in leaf polarities is of interest from an evolutionary viewpoint. To reveal the mechanism of unifacial leaf development and evolution, I focused on genus Juncus (Juncaceae) as a model system. In this review, I summarize recent advances in leaf polarity specification in angiosperms, and present my recent approaches to reveal the mechanism of unifacial leaf development and evolution.

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A variegated leaf of Hedera helix is composed of green and white mesophyll cells with and without photosynthetic capacity, respectively. We measured the photosynthesis and dark respiration rates, as well as CO₂ compensation points, of H. helix leaves with various extents of variegation. The photosynthetic rate (on an area basis) of the variegated leaves increased almost linearly according to the increase in the proportion of green area to total leaf area. In contrast, dark respiration rate was nearly constant irrespective of the extent of leaf variegation. These results suggest that chloroplast dysfunction in white mesophyll cells did not drastically affect photosynthetic activity of green mesophyll cells, or respiratory rates of both green and white mesophyll cells. CO₂ compensation point was elevated when the proportion of green area became extremely low, indicating that the proportion of non-photosynthetic cells within a photosynthetic organ could affect its CO₂ compensation point.

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To determine the precise morphological structure of compound bud in one axil of Armeniaca mume, we observed their development and anatomy in detail. A small bud was initiated in the axil of a scale-like prophyll of main axillary bud subtended by a foliage leaf. The small bud developed and was added to the main one to form the compound bud. This indicates the additional bud in the axil in Armeniaca mume is not an accessory bud, but independent of the main axillary bud. We concluded that the morphological homology in the structure of compound bud between Armeniaca mume and Amygdalus persica.

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