Function of GAP-43 for axon regeneration after spinal cord injury

• Project/Area Number: 17K10926
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Orthopaedic surgery
• Research Institution: Niigata University
• Principal Investigator: Watanabe Kei 新潟大学, 医歯学総合病院, 講師 (40597671)
• Co-Investigator(Kenkyū-buntansha): 五十嵐 道弘 新潟大学, 医歯学系, 教授 (50193173)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Project Status: Completed (Fiscal Year 2019)
• Budget Amount: ¥4,680,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥1,080,000); Fiscal Year 2019: ¥520,000 (Direct Cost: ¥400,000、Indirect Cost: ¥120,000); Fiscal Year 2018: ¥1,950,000 (Direct Cost: ¥1,500,000、Indirect Cost: ¥450,000); Fiscal Year 2017: ¥2,210,000 (Direct Cost: ¥1,700,000、Indirect Cost: ¥510,000)
• Keywords: 成長円錐 / 軸索再生 / リン酸化プロテオミクス / 神経成長タンパク / MAP1B / 神経軸索再生 / リン酸化 / 脊髄損傷 / 神経円錐 / GAP-43 / 再生医学 / 脳・神経 / 細胞・組織

Outline of Final Research Achievements

Relationship between extending axons in developing and regenerating neurons and microtubule-associated protein 1B (MAP1B) as the most frequently phosphorylated protein presented in the growth cone was investigated. We produced phospho-specific antibodies against phosphorylated serines at positions 25 and 1201 of MAP1B that specifically recognize growing axons both in cultured neurons and in vivo in various regions of the embryonic brain. Following sciatic nerve injury, transected and sutured nerves revealed that regenerating axons were specifically recognized by these antibodies. These results suggest that these MAP1B phosphorylation sites are specifically involved in axon growth and that phospho-specific antibodies against MAP 1B are useful markers of growing/regenerating axons.

Academic Significance and Societal Importance of the Research Achievements

今回、成長円錐のリン酸化プロテオミクス解析の結果を足掛かりとして、未解明であったMAP1Bリン酸化部位に対する特異抗体を使用して染色性を検討した。今後、本手法をモデルケースとして、さらなる軸索再生の病態解析の進歩が期待できる。
さらにMAP1Bをターゲットとして、脊髄損傷モデルを用いた再生軸索の評価を行い、脱リン酸化酵素を阻害するなどMAP1Bリン酸化レベルを高める介入の検証を行うことで、難治性の脊髄損傷に対する新たな分子生物学的評価法や治療戦略の確立の足がかりとなる。

Research Products

• [Journal Article] Phosphoproteomic and Bioinformatic Methods for Analyzing Signaling in Vertebrate Axon Growth and Regeneration (2020)
  • Author(s): Igarashi M, Kawasaki A, Ishikawa Y, Honda A, Okada M, Okuda S.
  • Journal Title: Journal of Neuroscience Methods Volume: 339 Pages: 108723-108723
  • DOI: 10.1016/j.jneumeth.2020.108723
  • Peer Reviewed / Open Access
• [Journal Article] Phosphorylation sites of microtubule-associated protein 1B (MAP1B) involved in axon growth and regeneration (2019)
  • Author(s): Ishikawa Y, Okada M, Honda A, Ito Y, Tamada A, Endo N, Igarashi M
  • Journal Title: Molecular Brain Volume: 12 Issue: 1 Pages: 31711525-31711525
  • DOI: 10.1186/s13041-019-0510-z
  • Peer Reviewed / Open Access
• [Presentation] MAP1BのS25・S1201リン酸化が末梢神経の再生過程に関与する (2019)
  • Author(s): 石川裕也、渡邊慶、岡田正康、遠藤直人、五十嵐道弘
  • Organizer: 第60回新潟生化学懇話会』
• [Presentation] 発生脳におけるMAP1Bの高頻度リン酸化部位 (2019)
  • Author(s): 石川裕也、本多敦子、伊藤泰行、河嵜麻実、玉田篤史、遠藤直人、五十嵐道弘
  • Organizer: 第42回日本神経科学大会、第62回日本神経化学大会
• [Presentation] 末梢神経再生におけるMAP1B新規リン酸化部位の解析 (2019)
  • Author(s): 石川裕也、渡邊慶、岡田正康、遠藤直人、五十嵐道弘
  • Organizer: 第34回日本整形外科学会基礎学術集会
• [Presentation] The MAP1B phosphorylation sites specifically localized in the developing brain and in the regenerating peripheral nerves (2019)
  • Author(s): Ishikawa Y, Okada M, Honda A, Ito Y, Tamada A, Endo N, Igarashi M
  • Organizer: Neuroscience 2019
  • Int'l Joint Research