Monoclonal antibody that activates the ghrelin receptor and its application to the crystal structure analysis

• Project/Area Number: 26650025
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Structural biochemistry
• Research Institution: Kurume University
• Principal Investigator: Kojima Masayasu 久留米大学, 分子生命科学研究所, 教授 (20202062)
• Research Collaborator: Shiimura Yuki
• Project Period (FY): 2014-04-01 – 2017-03-31
• Project Status: Completed (Fiscal Year 2016)
• Budget Amount: ¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000); Fiscal Year 2015: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000); Fiscal Year 2014: ¥2,340,000 (Direct Cost: ¥1,800,000、Indirect Cost: ¥540,000)
• Keywords: グレリン / オクタン酸 / グレリン受容体 / GPCR / 脂肪酸修飾 / モノクローナル抗体 / ナノボディ / 立体構造認識抗体 / アルパカ / 結晶構造解析

Outline of Final Research Achievements

In order to clarify how this fatty acid modified ghrelin binds to and activates the ghrelin receptor, we started on elucidating the crystal structure of the ghrelin receptor. However, the ghrelin receptor is a typical GPCR, and it is generally difficult to analyze the crystal structure of GPCR. Furthermore, it is more difficult to analyze the crystal structure of an active form receptor with an agonist bound thereto.
In this study, we tried to prepare monoclonal antibodies that act on the ghrelin receptor and can activate it. We planned to elucidate the crystal structure of the active ghrelin receptor by applying the monoclonal antibody to enlarge the hydrophilic surface of the ghrelin receptor and increasing its thermal stability.
As a result, we have obtained antibodies recognizing the steric structure of the ghrelin receptor, and are now applied the antibodies to the crystallization of the ghrelin receptor.

Research Products

• [Journal Article] Ghrelin improves dystonia and tremor in patients with Rett syndrome: A pilot study (2017)
  • Author(s): Yuge K, Hara M, Okabe R, Nakamura Y, Okamura H, Nagamitsu S, Yamashita Y, Orimoto K, Kojima M, Matsuishi T
  • Journal Title: J Neurol Sci Volume: 377 Pages: 219-223
  • DOI: 10.1016/j.jns.2017.04.022
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] 1．Ghrelin activation and neuropeptide Y elevation in response to medium chain triglyceride administration in anorexia nervosa patients (2017)
  • Author(s): Kawai K, Nakashima M, M Kojima M, Yamashita S, Takakura S, Shimizu M, Kubo C,Sudo N
  • Journal Title: Clinical nutrition ESPEN Volume: １７ Pages: 100-104
  • DOI: 10.1016/j.clnesp.2016.10.001
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Ghrelin O-acyltransferase (GOAT), a specific enzyme that modifies ghrelin with a medium-chain fatty acid (2016)
  • Author(s): Kojima M, Hamamoto A, Sato T
  • Journal Title: J Biochem Volume: 160 Issue: 4 Pages: 189-194
  • DOI: 10.1093/jb/mvw046
  • Peer Reviewed / Acknowledgement Compliant
• [Journal Article] The nutrient-responsive hormone CCHamide-2 controls growth by regulating insulin-like peptides in the brain of Drosophila melanogaster (2015)
  • Author(s): Sano H, Nakamur A, Texada M, Truma J, Ishimoto H, Kamikouchi A, Nibu Y, Kume K, Ida T, Kojima M
  • Journal Title: PLoS Genetics Volume: 11 Issue: 5 Pages: 1-26
  • DOI: 10.1371/journal.pgen.1005209
  • Peer Reviewed / Open Access / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Ghrelin is required for dietary restriction-induced enhancement of hippocampal neurogenesis: lessons from ghrelin knockout mice (2015)
  • Author(s): Kim Y, Kim S, Kim C, Sato T, Kojima M, Park S
  • Journal Title: Endocrine Journal Volume: 62 Issue: 3 Pages: 269-275
  • DOI: 10.1507/endocrj.EJ14-0436
  • NAID: 130005060852
  • ISSN: 0918-8959, 1348-4540
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Ghrelin. (2015)
  • Author(s): Muller T.D., Kojima M, Bloom S, Bowers C.Y, Casanueva F, Cowley M, Dickson S, Inui A, Nakazato M, Nass R, Perez-Tilve D, Pfluger, P.T., Schwartz T, Seeley R, Sleeman M, Smith R.G., Sun Y, Sussel L, Tong J, Thorner M.O., van der Lely A.J., van der Ploeg L, Zigman J, Kangawa K, Horvath T, Tschop M.H, et al
  • Journal Title: Molecular Metabolism Volume: 未定 Issue: 6 Pages: 437-460
  • DOI: 10.1016/j.molmet.2015.03.005
  • Peer Reviewed / Open Access
• [Journal Article] Low glucose-induced ghrelin secretion is mediated by ATP-sensitive potassium channel. (2015)
  • Author(s): Manami Oya, Tetsuya Kitaguchi, Kazuki Harada, Rika Numano, Takahiro Sato, Masayasu Kojima and Takashi Tsuboi.
  • Journal Title: J Endocrinol Volume: 226 Issue: 1 Pages: 25-34
  • DOI: 10.1530/joe-15-0090
  • Peer Reviewed / Open Access / Acknowledgement Compliant
• [Journal Article] Voluntary exercise contributed to an amelioration of abnormal feeding behavior, locomotor activity and ghrelin production concomitantly with a weight reduction in high fat diet-induced obese rats (2015)
  • Author(s): Mifune H, Tajiri Y, Nishi Y, Hara K, Iwata S, Tokubuchi I, Mitsuzono R, Yamada K, Kojima M
  • Journal Title: Peptides Volume: 71 Pages: 49-55
  • DOI: 10.1016/j.peptides.2015.06.007
  • Peer Reviewed
• [Presentation] 放射線被ばく後のグレリン産生・分泌動態とグレリンによる血球保護効果の検討 (2016)
  • Author(s): 西芳寬、那須沙織、細田洋司、御船弘治、久志野彰寛、田中永一郎、児島将康
  • Organizer: 第89回日本内分泌学会学術総会
  • Place of Presentation: 京都国際会館
• [Presentation] グレリン遺伝子欠損マウスの制限給餌下における自発運動について (2016)
  • Author(s): 御船弘治、原健人、坂井勇介、岩田慎平、西芳寬、田尻祐司、児島将康、満園良一
  • Organizer: グレリン遺伝子欠損マウスの制限給餌下における自発運動について
  • Place of Presentation: 京都国際会館
• [Presentation] 摂餌に関する記憶学習およぼ探索行動に及ぼすグレリンの役割 (2016)
  • Author(s): 佐藤貴弘、大石佳苗、児島将康
  • Organizer: グレリン遺伝子欠損マウスの制限給餌下における自発運動について
  • Place of Presentation: 京都国際会館
• [Presentation] グレリン受容体の大量発現と結晶化 (2015)
  • Author(s): 椎村祐樹、小林拓也、児島将康、岩田想
  • Organizer: 第12回GPCR研究会
  • Place of Presentation: 日本科学未来館 未来館ホール（東京、お台場）
  • Year and Date: 2015-05-15 – 2015-05-16
• [Presentation] 高脂肪食負荷マウスにおけるグレリン末梢投与後の摂餌行動 (2015)
  • Author(s): 御船弘治、原健人、西芳寛、岩田慎平、徳淵市朗、田尻祐司、満園良一、山田研太郎、児島将康
  • Organizer: 第88回日本内分泌学会学術総会
  • Place of Presentation: ホテルニューオータニ東京（東京都千代田区）
  • Year and Date: 2015-04-23
• [Presentation] 脳温に及ぼすグレリン作用の解析 (2015)
  • Author(s): 佐藤貴弘、大石佳苗、児島将康
  • Organizer: 第88回日本内分泌学会学術総会
  • Place of Presentation: ホテルニューオータニ東京（東京都千代田区）
  • Year and Date: 2015-04-23
• [Book] 下垂体疾患診療マニュアル (2016)
  • Author(s): 児島将康（分担）
  • Total Pages: 285
  • Publisher: 診断と治療社