This is the May 1999 issue of Protein Nucleic Acid Enzyme. *There are no writings or underlines.* Preface Hideyoshi Yokosawa, Keiji Tanaka* Graduate School of Pharmaceutical Sciences, Hokkaido University, *Tokyo Metropolitan Institute of Medical Science Protein Nucleic Acid Enzyme 44 (6) 731-731, 1999. What is the Ubiquitin World? Hideyoshi Yokosawa Graduate School of Pharmaceutical Sciences, Hokkaido University, Department of Biochemistry, Division of Biomolecular Pharmacology Ubiquitination Ligation System - From Discovery to the Present - Keiji Tanaka Department of Molecular Oncology, Tokyo Metropolitan Institute of Medical Science Ubiquitin-like Proteins and Their Protein Modification Systems Tomoki Chiba, Fumio Ohsaka* Department of Molecular Oncology, Tokyo Metropolitan Institute of Medical Science, *ERATO Kato Protein Ecosystem Project, Japan Science and Technology Agency Deubiquitinating Enzymes - A Huge Gene Family - Toshiaki Suzuki, Takayuki Kawakami* Department of Molecular Oncology, Tokyo Metropolitan Institute of Medical Science, *Department of Gastroenterology, Graduate School of Medicine, University of Tokyo Ubiquitin System and Stress Response Kazuhiro Iwai Graduate School of Biostudies, Kyoto University, Department of Cognitive and Information Sciences Protein Quality Control Mechanism by Ubiquitin/Proteasome Fumitoshi Tokunaga Faculty of Science, Himeji Institute of Technology, Department of Life Science Molecular Mechanisms of Ubiquitin Diseases - Diseases Related to Ubiquitin/Proteasome - Tadashi Anan, Mitsuyoshi Nakao Department of Oncology, School of Medicine, Kumamoto University Systematic Preservation of Amphibians Hitoshi Okumoto, Masayuki Sumida, Katsutoshi Yoshiri Amphibian Research Center, Faculty of Science, Hiroshima University Systematic Preservation of Zebrafish Hiroyuki Takeda Graduate School of Science, Nagoya University, Department of Biological Sciences Principles of Near-Field Optics and Its Application to Biological Sciences Kiwamu Saito, Takashi Funatsu* Faculty of Science, Kanazawa University, Department of Physics, *Faculty of Science and Engineering, Waseda University, Department of Physics Automatic Recording Technology of Oxygen Equilibrium Curve Precise Measurement of Gas Ligand Binding (2) Kiyohiro Imai, A. H. Mohammed Mawjood Graduate School of Medicine, Osaka University, Department of Information Physiology, Division of Information Transmission Medicine Capillary Electrophoresis - From Metal Ions to Genes (4) What are the Problems and Future Developments? Keiko Kitagishi, Hiromi Yamada Application Development Department, Otsuka Electronics Co., Ltd. What Research Means to Me - My Job Position Hideki Sakamoto Planning Division, Science and Technology Promotion Bureau, Science and Technology Agency