細胞間接着による細胞増殖の制御機構

• Project/Area Number: 14770049
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Single-year Grants
• Research Field: General medical chemistry
• Research Institution: Osaka University
• Principal Investigator: 入江 賢児 大阪大学, 医学系研究科, 助教授 (90232628)
• Project Period (FY): 2002 – 2003
• Project Status: Completed (Fiscal Year 2003)
• Budget Amount: ¥3,900,000 (Direct Cost: ¥3,900,000); Fiscal Year 2003: ¥1,500,000 (Direct Cost: ¥1,500,000); Fiscal Year 2002: ¥2,400,000 (Direct Cost: ¥2,400,000)
• Keywords: 細胞増殖 / 細胞接着 / 細胞運動 / ネクチン / カドヘリン / アドヘレンスジャンクション / タイトジャンクション / がん / Nectin-Afadin系 / Cadherin-Catenin系

Research Abstract

細胞増殖のシグナル系と細胞の接着・運動のシグナル系との間には密接なクロストークが存在し、細胞の接着阻害の破綻が、がん細胞の増殖、浸潤、転移へとつながる。私共は、新しい細胞間接着機構ネクチン-アファディン系を見出し、アドヘレンスジャンクション(AJに局在することを明らかにしている。ネクチン-アファディン系は、カドヘリン-カテニン系と協調してAJの形成を制御している。本年度は、ネクチン-アファディン系を介した細胞の接着と運動のシグナル系を詳細に解析し、以下の成果を得た。
(1)ネクチン-3が、運動している細胞の先端部に局在するネクチン様分子Necl-5とヘテロな接着を形成し、この接着がAJ形成の初期で機能することを見出した。
(2)アファディンに直接結合する因子として、ADIP, LMO7を見出した。ADIP, LMO7はα-アクチニンを介してカテニンと結合し、AJ形成におけるネクチン-アファディン系とカドヘリン-カテニン系を連結する因子として機能することが示唆された。
(3)ネクチン-1およびネクチン-3のノックアウトマウスを作製した。ネクチン-1およびネクチン-3ノックアウトマウスは生存可能であったが、どちらも眼球が小さいという表現型を示した。野生型マウスにおいて、ネクチン-1とネクチン-3は毛様体の色素上皮と無色素上皮の間の接着部位に局在しており、ネクチン-1およびネクチン-3ノックアウトマウスでは毛様体のこの部分が剥がれていた。以上の結果から、ネクチン-1とネクチン-3の接着が毛様体の形成に必須の役割を果たしていることが明らかとなった。
このように本年度は、細胞間接着機構ネクチン-アファディン系による細胞増殖・運動の制御機構について、当初の計画以上の成果をあげることができた。

Research Products

• [Publications] Asada, M.: "ADIP, a novel afadin- and α-actinin-binding protein localized at cell-cell adherens junctions."J.Biol.Chem.. 278・6. 4103-4111 (2003)
• [Publications] Toi, H.: "She4p/Dim1p interacts with the motor domain of unconventional myosins in the budding yeast, Saccharomyces cerevisiae."Mol.Biol.Cell. 14・6. 2237-2249 (2003)
• [Publications] Katata, T.: "Involvement of nectin in the localization of IQGAP1 at the cell-cell adhesion sites through the actin cytoskeleton in Madin-Darby canine kidney cells."Oncogene. 22・14. 2097-2109 (2003)
• [Publications] Honda, T.: "Regulation by nectin of the velocity of the formation of adherens junctions and tight junctions."Biochem.Biophys.Res.Commun.. 306・1. 104-109 (2003)
• [Publications] Honda, T.: "Antagonistic and agonistic effects of an extracellular fragment of nectin on formation of E-cadherin-based cell-cell adhesion."Genes Cells. 8・1. 51-63 (2003)
• [Publications] Honda, T.: "Cdc42 and Rac small G proteins activated by trans-interactions of nectins are involved in activation of c-Jun N-terminal kinase, but not in association of nectins and cadherin to form adherens junctions, in fibroblasts."Genes Cells. 8・5. 481-491 (2003)
• [Publications] Yamada, A: "Nectin-dependent localization of synaptic scaffolding molecule (S-SCAM) at the puncta adherentia junctions formed between the mossy fibre terminals and the dendrites of pyramidal cells in the CA3 area of the mouse hippocampus."Genes Cells. 8・12. 985-994 (2003)
• [Publications] Inagaki, M.: "Nectin-dependent localization of ZO-1 at puncta adhaerentia junctions between the mossy fiber terminals and the dendrites of the pyramidal cells in the CA3 area of adult mouse hippocampus."J.Comp.Neurol.. 460・4. 514-524 (2003)
• [Publications] Takai, Y.: "Nectins and nectin-like molecules : Roles in cell adhesion, migration, and polarization."Cancer Science. 94・8. 655-667 (2003)
• [Publications] Yamamoto, Y.: "Vmac : A novel protein associated with vimentin-type intermediate filament in podocytes of rat kidney."Biochem.Biophys.Res.Commun.. 315・4. 1120-1125 (2004)
• [Publications] Yamamoto, Y.: "Direct binding of the human homologue of the drosophila disc large tumor suppressor gene to seven-pass transmembrane proteins, tumor endothelial marker 5 (TEM5) and a novel TEM5-like protein."Oncogene. in press. (2004)
• [Publications] Irie, K.: "Roles of nectins in cell adhesion, signaling, and polarization."Handbook of Experimental Pharmacology. in press. (2004)
• [Publications] Irie, K.: "The Khd1 protein, which has three KH RNA-binding motifs, is required for proper localization of ASH1 mRNA in yeast"EMBO J.. 21・5. 58-67 (2002)
• [Publications] Ozaki-Kuroda, K.: "Nectin couples cell-cell adhesion and the actin scaffold at heterotypic testicular junctions"Curr. Biol.. 12・13. 1145-1150 (2002)
• [Publications] Fukuhara, A.: "Involvement of nectin in the localization of junctional adhesion molecule at tight junctions"Oncogene. 21・50. 7642-7655 (2002)
• [Publications] Momose, Y.: "Role of the second immunoglobulin-like loop of nectin in cell-cell adhesion"Biochem. Biophys. Res. Commun.. 293・1. 45-49 (2002)
• [Publications] Tanaka, Y.: "Ectodomain shedding of nectin-1α by SF/HGF and TPA in MDCK cells"Biochem. Biophys. Res. Commun.. 299・3. 472-478 (2002)
• [Publications] Fukuhara, A.: "Role of nectin in organization of tight junctions in epithelial cells"Genes Cells. 7・10. 1059-1072 (2002)
• [Publications] Asada, M.: "ADIP, a novel afadin-and α-actinin-binding protein localized at cell-cell adherens junctions"J. Biol. Chem.. 278・6. 4103-4111 (2003)
• [Publications] Honda, T.: "Antagonistic and agonistic effects of an extracellular fragment of nectin on formation of E-cadherin-based cell-cell adhesion"Genes Cells. 8・1. 51-63 (2003)
• [Publications] Toi, H.: "She4p/Dim1p interacts with the motor domain of unconventional myosins in the budding yeast, Saccharomyces cerevisiae"Mol. Biol. Cell. (in press). (2003)
• [Publications] Katata, T.: "Involvement of nectin in the localization of IQGAP1 at the cell-cell adhesion sites through the actin cytoskeleton in Madin-Darby canine kidney cells"Oncogene. (in press). (2003)
• [Publications] Honda, T.: "Cdc42 and Rac small G proteins activated by trans-interactions of nectins are involved in activation of c-Jun N-terminal kinase, but not in association of nectins and E-cadherin to form adherens junctions, in fibroblasts"Genes Cells. (in press). (2003)
• [Publications] Inagaki, M.: "Nectin-dependent localization of ZO-1 at puncta adhaerentia junctions between the mossy fiber terminals and the dendrites of the pyramidal cells in the CA3 area of adult mouse hippocampus"J. Comp. Neurol.. (in press). (2003)