道管形成過程での液胞崩壊の研究

• Project/Area Number: 10219201
• Research Category: Grant-in-Aid for Scientific Research on Priority Areas
• Allocation Type: Single-year Grants
• Review Section: Biological Sciences
• Research Institution: The University of Tokyo
• Principal Investigator: 馳澤 盛一郎 (2001-2002) 東京大学, 大学院・新領域創成科学研究科, 教授 (40172902); 福田 裕穗 (福田 裕穂) (1998-2000) 東京大学, 大学院・理学系研究科, 教授 (10165293)
• Co-Investigator(Kenkyū-buntansha): 福田 裕穂 東京大学, 大学院・理学系研究科, 教授 (10165293) ; 馳澤 盛一郎 東京大学, 大学院・新領域創成科学研究科, 教授 (40172902) ; 出村 拓 東京大学, 大学院・理学系研究科, 助手 (40272009)
• Project Period (FY): 1998 – 2002
• Project Status: Completed (Fiscal Year 2002)
• Budget Amount: ¥54,000,000 (Direct Cost: ¥54,000,000); Fiscal Year 2002: ¥8,100,000 (Direct Cost: ¥8,100,000); Fiscal Year 2001: ¥9,000,000 (Direct Cost: ¥9,000,000); Fiscal Year 2000: ¥8,900,000 (Direct Cost: ¥8,900,000); Fiscal Year 1999: ¥17,000,000 (Direct Cost: ¥17,000,000); Fiscal Year 1998: ¥11,000,000 (Direct Cost: ¥11,000,000)
• Keywords: 液胞 / プログラム細胞死 / 管状要素 / ヒャクニチソウ / タバコBY-2 / ヌクレアーゼ / TVM / AtVam3p / 細胞周期 / タバコBY-2細胞 / 微小管 / 核 / システインプロテアーゼ / 管状要素分化 / 細胞死 / リパーゼ / DNアーゼ / 核DNA / プロテアソーム / タバコBY2細胞 / プロベネシド / 形質転換培養細胞

Research Abstract

我々は高等植物細胞の形態形成における液胞の寄与について研究を進めている。今年度は、液胞の立体構造の詳細な経時観察のため、シロイヌナズナのsyntaxinファミリーに属するAt Vam3pとGFPの融合タンパク質を恒常的に発現するタバコBY-2細胞の形質転換株BY-GV(transgenic <BY>-2 cells stably expressing GFP-AtVam3p fusion protein)を確立した。このBY-GV細胞を用いて、共焦点レーザー顕微鏡によって得られた連続光学切片をもとに、新規に独自で開発した立体画像構築ソフトSSR(stereo-structure reconstructor)による立体画像構築とモデリングを行った。その結果、TVM(tubular structure of vacuolar membrane)を含む液胞構造の立体的な構成と、細胞周期の進行に伴う動態の全容が明らかになった。
また我々は、これまでにヒャクニチソウ葉肉細胞から管状要素への分化転換系において、道管形成の分子機構について詳細な解析を行い、液胞が細胞の自己分解過程で崩壊することによりプログラム細胞死の中心的役割を担うことを明らかにしてきた。特に、細胞死特異的発現を示すS1ヌクレアーゼ遺伝子(ZEN1)の産物が液胞に特異的に蓄積されること、液胞崩壊後の核分解に直接関与していることなどを示してきた。本年度は、これ以外にCa/Mg依存ヌクレアーゼが細胞死の時に一過的に発現することを明らかにした。また、ZEN1以外の細胞死特異的システインプロテアーゼZCP4,細胞死特異的ヌクレアーゼZeRNase1が、分化中の管状要素でのみ、小胞体、ゴルジ体を経由して液胞に蓄積することを明らかにした。

Research Products

• [Publications] 馳澤 盛一郎: "Dynamic changes and roles of cytoskeleton during cell cycle in higher plant cells"International Review of Cytology. 214. 161-191 (2002)
• [Publications] 柳川 由紀: "Cell-Cycle Dependent Dynamic Change of 26S Proteaso me Distribution in Tobacco BY-2 Cells"Plant & Cell Physiology. 43. 604-613 (2002)
• [Publications] 朽名 夏麿: "Dynamic organization of vacuolar and microtubule structures during cell cycle progression in synchronized tobacco BY-2 cells"Plant & Cell Physiology. 43. 965-973 (2002)
• [Publications] 中名生 幾子: "Preferential and asymmetrical accumulation of a Rac small GTPase mRNA in differentiating xylem cells of Zinnia elegans"Plant & Cell Physiology. 43. 1484-1492 (2002)
• [Publications] 井藤 純: "ZEN1 is a key enzyme in degradation of nuclear DNA during programmed cell death of tracheary elements"Plant Cell. 14. 3201-3211 (2002)
• [Publications] 出村 拓: "Visualization by comprehensive microarray analysis of gene expression programs during transdifferentition of mesophyll cells"Proc.Natl.Acad.Sci.USA.. 99. 15794-15799 (2002)
• [Publications] 熊谷 史: "γ-Tubulin distribution during cortical microtubule reor ganization at the M/G_1 interface in tobacco BY-2 cells"European Journal of Cell Biology. 82. 43-51 (2003)
• [Publications] 熊谷 史: "Dynamic organization of microtubules and microfilaments during cell cycle progression in higher plant cells"Plant Biology. 3. 4-16 (2001)
• [Publications] 熊谷 史: "Fate of nascent microtubules organized at the M/G1 interface, as visualized by synchronized tobacco BY-2 cells stably expressing GFP-tubulin : Time-sequence observations of the reorganization of cortical microtubules in living plant cells"Plant & Cell Physiology. 42. 723-732 (2001)
• [Publications] 馳澤 盛一郎: "Dynamic changes and the role of the cytoskeleton during the cell cycle in higher plant cells"International Review of Cytology. 214. 161-191 (2002)
• [Publications] 遠藤 暁詩: "Inhibition of proteasome activity by the TED4 protein in extracellular space : a novel mechanism for protection of living cells from injury caused by dying cells"Plant & Cell Physiology. 42. 9-19 (2001)
• [Publications] 山本 亮: "Brassinosteroid levels increase drastically prior to morphogenesis of tracheary elements"Plant Physiology. 125. 556-563 (2001)
• [Publications] 小原 圭介: "Direct evidence of active and rapid nuclear degradation triggered by vacuole rupture during programmed cell death in Zinnia"Plant Physiology. 125. 615-626 (2001)
• [Publications] 栗山 英夫: "Programmed cell death in developing tracheary elements"Recent Research Developments in Plant Physiology. 2. 199-212 (2001)
• [Publications] Fukuda,H.: "Programmed cell death of tracheary elements as a paradigm in plants."Plant Mol.Biol.. 44. 245-253 (2000)
• [Publications] Sugiyama,M.: "Endonuclease"Plant Mol.Biol.. 44. 389-397 (2000)
• [Publications] Nara-Sato,K.: "The rates of deceleration of nuclear and organellar DNA syntheses differ in the progenitor cells of the apical meristems during carrot somatic embryogenesis."Planta. 211. 457-466 (2000)
• [Publications] Koizumi,K.: "A series of novel mutants of Arabidopsis thaliana that are defective in the formation of continuous vascular network : Calling the auxin signal flow canalization hypothesis into question."Development. 217. 3197-3204 (2000)
• [Publications] Nakashima,J.: "Autolysis during in vitro tracheary element differentiation-Formation and location of the perforation."Plant Cell Physiol.. 41. 1267-1271 (2000)
• [Publications] Endo,S.: "Inhibition of proteasome activity by the TED4 protein in extracellular space : a novel mechanism for protection of living cells from injury caused by dying cells."Plant Cell Physiol.. 42. 9-19 (2001)
• [Publications] Yamamoto,R.: "Brassinosteroid levels increase drastically prior to morphogenesis of tracheary elements."Plant Physiol.. 125. 556-563 (2001)
• [Publications] Motose,H.: "Involvement of local intercellular communication in the differentiation of zinnia mesophyll cells into tracheary elements."Planta. (in press). (2001)
• [Publications] Motose,H.: "An arabinogalactan protein (s) is a key component of a fraction that mediates local intercellular communication involved in tracheary element differentiation of zinnia mesophyll cells."Plant Cell Physiol.. 42. 129-137 (2001)
• [Publications] Obara,K.: "Direct evidence of active and rapid nuclear degradation triggered by vacuole rupture during programmed cell death in Zinnia."Plant Physiol.. 125. 615-626 (2001)
• [Publications] Kuriyama,H.: "Regulation of tracheary element differentiation."J Plant Growth Reg.. (in press). (2001)
• [Publications] 出村拓: "細胞・組織の光学顕微鏡による観察"モデル植物ラボマニュアル(岩渕雅樹ら編集)、Springer. 35-40 (2000)
• [Publications] Usuda, H.: "Development of sink capacity of the "storage root" in a radish cultivar with a high ratio of "storage root" to shoot"Plant Cell Physiol.. 40. 369-377 (1999)
• [Publications] Tokuji, Y: "A rapid method for transformation of carrot (Daucus carota L.) by using direct somatic embryogenesis"Biosci. Biotechnol. Biochem.. 63. 519-523 (1999)
• [Publications] Tandon, P.: "Incorporation of fluorescence-conjugated anti-mouse immunoglobulin G into permiabilized Nicotiana tabacum BY-s cells"Plant Sci.. 140. 63-69 (1999)
• [Publications] Usuda, H.: "Development of sink capacity of the "storage root" in a radish cultivar with a low ratio of "storage root" to shoot"Plant Cell Physiol.. 40. 1210-1218 (1999)
• [Publications] Shinohara, N.: "Isolation of a vascular cell wall-specific monoclonal antibody recognizing a cell polarity by using a phage display subtraction method"Proc. Natl. Acad Sci. USA.. (in press). (2000)
• [Publications] Hiwatashi, Y.: "Tissue-specific localization of mRNA for carrot homeobox genes, CHBs"Plant Cell Physiol. (in press). (2000)
• [Publications] 福田裕穂: "維管束の分化"植物細胞工学シリーズ12. 12. 212-222 (1999)
• [Publications] 福田裕穂: "植物における形態形成―植物から学ぶしくみ"生体の科学. (印刷中). (2000)
• [Publications] Igarashi, M.: "Expression of the Zinnia TED3 promoter in developing tracheary elements of transgenic Arabidopsis." Plant Mol. Biol.36. 917-927 (1998)
• [Publications] Ozawa, S.: "Organogenic responses in tissue culture of srd mutants of Arabidopsis thaliana." Development. 125. 135-142 (1998)
• [Publications] Fukuda, H.: "Programming of Cell Death during Xylogenesis." J.Plant Res.111. 253-256 (1998)
• [Publications] Aoyagi, S.: "BEN1 and ZEN1 cDNAs encoding S1-type DNases that are involved in programmed cell death in plants." FEBS Lett.429. 134-138 (1998)
• [Publications] Usuda, H.: "Development of sink capacity of the “storage root" in a radish cultivar with a high ratio of “storage root" to shoot." Plant Cell Physiol.(in press). (1999)
• [Publications] Yamada,T.: "Apoptosis-Its role and mechanism" Business Center for Academic Societies Japan, Tokyo, 228 (1998)
• [Publications] 今関英雅: "植物ホルモンと細胞の形" 学会出版センター, 190 (1998)
• [Publications] 中村研三: "植物の生長-遺伝子から何が見えるか" クバプロ, 169 (1998)