A Chemorepulsive Effect of Semaphorin 3A on the Migration of GnRH Neurons in the Chick Forebrain.

2015 Fiscal Year Final Research Report

• Project/Area Number: 25460253
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: General anatomy (including histology/embryology)
• Research Institution: Juntendo University
• Principal Investigator: MURAKAMI Shizuko 順天堂大学, 医学部, 助教 (20255649)
• Co-Investigator(Kenkyū-buntansha): KOIKE Masato 順天堂大学, 医学部, 教授 (80347210) ; SASAKI Mitsuho 医薬基盤・健康・栄養研究所, 疾患モデル小動物研究室, プロジェクト研究員 (20432536)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: GnRHニューロン / 軸索ガイダンス分子 / セマフォリン３Ａ / ニューロン移動 / エレクトロポレーション / ニワトリ胚

Outline of Final Research Achievements

Gonadotropin-releasing hormone (GnRH)-producing neurons originate in the olfactory placode and migrate to the forebrain. In exploring the molecular mechanisms guiding GnRH neurons to their final locations in the forebrain, we found that chick semaphorin 3A (Sema3A) mRNA is expressed in the olfactory bulb and the restricted region of the dorsal septum region (DS) to which GnRH neurons tend to avoid approaching. Most migrating GnRH neurons expressed neuropilin-1 mRNA, a Sema3A receptor. To investigate the chemorepulsive effect of Sema3A on the migration of GnRH neurons in the forebrain, we misexpressed Sema3A by in ovo electroporation in the ventral part of the medial forebrain of embryonic day (E) 3.5. At E6.5-7, GnRH neurons entered the medial forebrain, but failed to migrate to the DS over the site in which Sema3A was misexpressed. These results suggest that Sema3A acts as a chemorepulsive cue for the migration of GnRH neurons in the chick forebrain.

Free Research Field

神経発生