翻訳後修飾による転写因子Ｔｃｆ／Ｌｅｆの活性制御の分子基盤と組織の維持・破綻

• Project Area: Regulation of signal transduction by post-translational modifications and its pathogenic dysregulation
• Project/Area Number: 23117525
• Research Category: Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
• Allocation Type: Single-year Grants
• Review Section: Biological Sciences
• Research Institution: Kyushu University
• Principal Investigator: 石谷 太 九州大学, 生体防御医学研究所, 准教授 (40448428)
• Project Period (FY): 2011-04-01 – 2013-03-31
• Project Status: Completed (Fiscal Year 2012)
• Budget Amount: ¥12,480,000 (Direct Cost: ¥9,600,000、Indirect Cost: ¥2,880,000); Fiscal Year 2012: ¥6,240,000 (Direct Cost: ¥4,800,000、Indirect Cost: ¥1,440,000); Fiscal Year 2011: ¥6,240,000 (Direct Cost: ¥4,800,000、Indirect Cost: ¥1,440,000)
• Keywords: Tcf/Lef / 翻訳後修飾 / Wntシグナル

Outline of Annual Research Achievements

Wnt-βカテニンシグナルは、初期胚発生における体軸形成だけでなく、幹細胞の運命決定制御を介して組織・器官の構築維持、そしてその破綻としての疾患発症（癌、糖尿病、精神疾患など）に深く関与している。Wnt-βカテニンシグナルの機能と制御の解明は、将来的な新たな医療技術の開発や創薬につながると期待されており、最もホットな研究課題の一つである。Wnt-βカテニンシグナルは、細胞が細胞間情報伝達分子Wntを受容することにより活性化する。Wnt-βカテニンシグナルが活性化した細胞では、転写因子Tcf/Lefが標的遺伝子の転写を誘導する。本研究では、Tcf/Lefの翻訳後修飾に注目して研究を行っている。　前年度までに、タンパク質リン酸化酵素NLKによるTcf/Lefリン酸化が、ヒト細胞株HEK293及びヒト子宮頸癌細胞株HeLaではTcf/Lefの活性を低下させ、その一方で、神経前駆細胞ではTcf/Lefの活性を促進することを見いだしていた。本年度は、NLKが大腸がん細胞株においてもNLKによるTcf/Lefリン酸化がTcf/Lefの活性を促進することや、NLKがWntシグナルを正に制御する細胞ではTcf/Lefの活性がHDAC1により抑制されており、NLKはTcf/LefとHDAC1の結合を解除することでWntシグナルを促進することを見いだした（投稿準備中）。　また、Tcf/Lefの翻訳後修飾制御の全貌を明らかにするために、Tcf/Lefの結合タンパク質と修飾部位を質量分析により解析した。その結果、多数の未知の翻訳後修飾酵素（キナーゼ、フォスファターゼ、ユビキチンリガーゼなど）をTcf/Lefの結合タンパク質として同定できた。また、Tcf/Lefの新たなリン酸化部位及びユビキチン化部位も同定した。今後これらについて詳細な解析を行う予定である。

Research Progress Status

24年度が最終年度であるため、記入しない。

Strategy for Future Research Activity

24年度が最終年度であるため、記入しない。

Research Products

• [Journal Article] Visualization and exploration of Tcf/Lef function using a highly responsive Wnt/β-catenin signaling-reporter transgenic zebrafish (2012)
  • Author(s): Shimizu N, Kawakami K, *Ishitani T
  • Journal Title: Developmental Biology Volume: 370. Issue: 1 Pages: 71-85
  • DOI: 10.1016/j.cellsig.2012.09.017
  • Peer Reviewed
• [Journal Article] Dual functions of DP1 promote biphasic Wnt-on and Wnt-off states during anteroposterior neural patterning. (2012)
  • Author(s): Kim WT, Kim H, Katanaev VL, Joon Lee S, Ishitani T, Cha B, Han JK, Jho EH.
  • Journal Title: EMBO Journal Volume: 31 Issue: 16 Pages: 3384-3397
  • DOI: 10.1038/emboj.2012.181
  • Peer Reviewed
• [Journal Article] Context-dependent dual and opposite roles of nemo-like kinase in the Wnt/β-catenin signaling (2012)
  • Author(s): Ishitani T
  • Journal Title: Cell Cycle Volume: 11 Issue: 9 Pages: 1743-1745
  • DOI: 10.4161/cc.20183
• [Journal Article] Visualization and exploration of Tcf/Lef function using a highly responsive Wnt/β-catenin signaling-reporter transgenic zebrafish. (2012)
  • Author(s): Shimizu N, Kawakami K, Ishitani T.
  • Journal Title: Developmental Biology Volume: 370 Issue: 1 Pages: 71-85
  • DOI: 10.1016/j.ydbio.2012.07.016
  • Peer Reviewed
• [Journal Article] NLK positively regulates Wnt/β-catenin signaling by phosphorylating LEF1 in neural progenitor cells (2012)
  • Author(s): Ota, S., Ishitani, S., Shimizu, N., Matsumoto, K., Itoh, M., and Ishitani. T
  • Journal Title: EMBO J Volume: 31 Issue: 8 Pages: 1904-1915
  • DOI: 10.1038/emboj.2012.46
  • Peer Reviewed
• [Presentation] Roles of two Ser/The kinases, NLK and Hipk2, in the regulation of Wnt/β-catenin signaling (2013)
  • Author(s): Tohru Ishitani
  • Organizer: 1st International Symposium on Protein Modifications in Pathogenic Dysregulation of Signaling
  • Place of Presentation: The Auditorium The Institute of Medical Science, The University of Tokyo
  • Year and Date: 2013-02-01
  • Invited
• [Presentation] Homeodomain-interacting protein kinase 2 regulates Wnt/beta-catenin and Wnt/PCP signaling pathways through stabilization of Dishevelled. (2013)
  • Author(s): Tohru Ishitani
  • Organizer: the 5th Strategic Conference of Zebrafish Investigators
  • Place of Presentation: The Asilomar Conference Grounds
  • Year and Date: 2013-01-19
• [Presentation] Homeodomain-interacting protein kinase 2 regulates Wnt/beta-catenin and Wnt/PCP signaling pathways through stabilization of Dishevelled. (2012)
  • Author(s): 清水 誠之、石谷 太
  • Organizer: 第35回日本分子生物学会年会
  • Place of Presentation: 福岡国際会議場
  • Year and Date: 2012-12-11
• [Presentation] Exploration of Tcf/Lef function using a highly responsive Wnt/β-catenin signaling-reporter transgenic zebrafish (2012)
  • Author(s): Nobuyuki Shimizu, Koichi Kawakami, and Tohru Ishitani
  • Organizer: 第18回小型魚類研究会
  • Place of Presentation: 京都大学芝蘭会館
  • Year and Date: 2012-09-22
• [Presentation] NLK positively regulates Wnt/β-catenin signalling by phosphorylating LEF1 in neural progenitor cells. (2012)
  • Author(s): Satoshi Ota, Shizuka Ishitani, Nobuyuki Shimizu, Kunihiro Matsumoto, Motoyuki Itoh, Tohru Ishitani
  • Organizer: 第35回日本神経科学大会
  • Place of Presentation: 名古屋国際会議場
  • Year and Date: 2012-09-18
• [Presentation] NLK positively regulates Wnt/β-catenin signalling by phosphorylating LEF1 in neural progenitor cells. (2012)
  • Author(s): Satoshi Ota, Shizuka Ishitani, Nobuyuki Shimizu, Kunihiro Matsumoto, Motoyuki Itoh, Tohru Ishitani
  • Organizer: EMBO conference 30 years of Wnt signaling
  • Place of Presentation: Egmond Ann Zee, Netherland
  • Year and Date: 2012-06-27
• [Presentation] Live imaging of Tcf/Lef activity in developing, growing, and regenerating tissues of the highly responsive Wnt/β-catenin signaling reporter-transgenic zebrafish (2012)
  • Author(s): Nobuyuki Shimizu and Tohru Ishitani
  • Organizer: the 10th International Conference on Zebrafish Development and Genetics
  • Place of Presentation: Madison, USA
  • Year and Date: 2012-06-20
• [Presentation] NLK positively regulates Wnt/β-catenin signalling by phosphorylating LEF1 in neural progenitor cells. (2012)
  • Author(s): Satoshi Ota, Shizuka Ishitani, Nobuyuki Shimizu, Kunihiro Matsumoto, Motoyuki Itoh, Tohru Ishitani
  • Organizer: the 10th International Conference on Zebrafish Development and Genetics
  • Place of Presentation: Madison, USA
  • Year and Date: 2012-06-20
• [Presentation] A dual and opposite role of NLK-mediated Lef1 phosphorylation on the Wnt/β-catenin signaling (2012)
  • Author(s): Tohru Ishitani, Shizuka Ishitani
  • Organizer: 第45回日本発生生物学会・第64回日本細胞生物学会 合同年会
  • Place of Presentation: 神戸国際会議場
  • Year and Date: 2012-05-28
• [Presentation] Homeodomain-interacting protein kinase 2 promotes Wnt signaling through stabilization of Dishevelled in vertebrate posterior development (2011)
  • Author(s): 清水誠之、石谷太
  • Organizer: 第34回日本分子生物学会年会
  • Place of Presentation: パシフィコ横浜
  • Year and Date: 2011-12-16
• [Presentation] Lef1 phosphorylation by NLK is essential for the Lef1-mediated Wnt/β-catenin signaling in neural progenitor cells (2011)
  • Author(s): Satoshi Ota, Shizuka Ishitani, Nobuyuki Shimizu, Kunihiro Matsumoto, Motoyuki Itoh, Tohru Ishitani
  • Organizer: 第34回日本分子生物学会年会
  • Place of Presentation: パシフィコ横浜
  • Year and Date: 2011-12-16
• [Presentation] Analysis of the spatiotemporal dynamics and its regulatory mechanisms of Wnt/β-catenin and Hedgehog signaling pathways using the transgenic zebrafish lines carrying the signaling reporters (2011)
  • Author(s): Nobuyuki Shimizu, Tohru Ishitani
  • Organizer: 第17回小型魚類研究会
  • Place of Presentation: 三島市東レ研修センター
  • Year and Date: 2011-09-08
• [Presentation] Lef1 phosphorylation by NLK is essential for the Lef1-mediated Wnt/β-catenin signaling in neural progenitor cells (2011)
  • Author(s): Satoshi Ota, Shizuka Ishitani, Nobuyuki Shimizu, Kunihiro Matsumoto, Motoyuki Itoh, Tohru Ishitani
  • Organizer: 第44回日本発生生物学会
  • Place of Presentation: 沖縄コンベンションセンター
  • Year and Date: 2011-05-20
• [Remarks] 石谷研究室プログレス
  • URL: http://www.bioreg.kyushu-u.ac.jp/labo/crs/sub11.html
• [Remarks]
  • URL: http://www.bioreg.kyushu-u.ac.jp/labo/crs/sub11.html