ネズミの丸における無差別精子分裂のための血管系に関連したニッチ

Shosei Yoshida¹, Mamiko Sukeno, Yo-Ichi Nabeshima

¹Department of Pathology and Tumor Biology, Graduate School of Medicine, Kyoto University, Kyoto, Japan. shosei@lmls.med.kyoto-u.ac.jp

Science (New York, N.Y.)

|September 8, 2007

まとめ

哺乳類の精子生成は,ユニークな幹細胞のニッチに依存しています. この研究は,血管ネットワークと間位細胞をこのニッチの重要な構成要素として特定し,精子幹細胞の局所化と分化を導く.

科学分野:

生殖生物学生殖生物学
幹細胞生物学幹細胞生物学とは
発達生物学発達生物学とは

背景:

哺乳類の精子生成には,その強力な幹細胞システムのために,特殊なマイクロ環境,またはニッチが必要です.
哺乳類の生殖系ニッチの正確な位置と構成は未確認のままである.
ドロソフィラ (Drosophila) やC.elegansのようなモデル生物から得られた既存のモデルは,独特で偏ったニッチ構造を示している.

研究の目的:

哺乳類の丸における無差別精子分裂症 (A(undiff)) のニッチを特定し,特徴づけること.
ニッチ構造と精子幹細胞の動態の関係を理解する.
哺乳類の生殖系ニッチを,他の種に見られるものと比較するために.

主な方法:

緑色光タンパク質にラベルを貼った無差別精子管のタイムラップス画像を用いた.
詳細な構造分析のために3次元再構成技術を使用しました.
生理学的関連性を維持するために,無傷の丸を観察した.

主要な成果:

A ((undiff) は,無傷の丸内の血管ネットワークと関連する間位細胞 (レイディグ細胞) に偏った局所化を示した.
異なる精子細胞は,これらの血管関連ニッチ領域から離れていった.
A ((undiff) の再配置は,丸血管のパターンの変化と一致することが観察されました.

結論:

哺乳類の生殖系ニッチは,血管系パターンの形成の結果として確立されることが提案されています.
この発見は,無脊椎動物に見られる既定で偏ったニッチ構造と対照的です.
血管ネットワークは,哺乳類の精子幹細胞のニッチを組織する上で重要な役割を果たします.

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