Bリンパ球系統へのコミットメントは,転写因子Pax5に依存しています
S L Nutt1, B Heavey, A G Rolink
1Research Institute of Molecular Pathology, Vienna, Austria.
Nature
|October 19, 1999
まとめ
Pax5遺伝子はB細胞の発達に不可欠である. Pax5が欠けると,プロB細胞は他のタイプの血液細胞に変容し,B系統へのコミットメントにおけるPax5の役割を強調します.
科学分野:
- 免疫学 免疫学とは
- 発達生物学 発達生物学とは
- 遺伝学 遺伝学とは
背景:
- Pax5遺伝子はB細胞特異活性化タンパク質 (BSAP) をコードする.
- Pax5は,B-リンパ球系統の進行に不可欠であり,生体内でプロ-B細胞段階を超えています.
- プロB細胞は,特定の条件下でPax5なしでインビトロで増殖することができる.
研究 の 目的:
- in vitro B細胞の分化におけるPax5の役割を調査する.
- Pax5欠乏型プロB細胞が系統制限されているかどうかを判断する.
- Pax5が系統のコミットメントと遺伝子発現にどのように影響するかを理解する.
主な方法:
- 培養Pax5-欠乏 (Pax5-/-) プロB細胞をインビトロで培養する.
- レトロウイルストランスデュークションによるPax5発現の回復.
- シトカインでPax5-/- プロB細胞を刺激し,分化可能性を評価する.
- Pax5復元とPax5復元のないPax5-/-プロB細胞の遺伝子発現プロフィールを分析する.
主要な成果:
- Pax5-/- プロB細胞は,Pax5を再導入しない限り,インビトロではB細胞に微分化することができなかった.
- Pax5-/- プロB細胞は多効力を発揮し,マクロファージ,オステオクラスト,デンドリット細胞,粒細胞,自然キラー細胞に微分化しました.
- Pax5-/- プロB細胞は,様々な血液生成系からの遺伝子の乱交的転写を示した.
- 抑制されたPax5活性の回復 系統不適切な遺伝子発現.
結論:
- Pax5は,B細胞のプロB細胞からのB細胞の微分化に不可欠である.
- Pax5の機能は,代替の系統運命を抑制し,それによってB系統のコミットメントを強制する.
- Pax5は,血球造血幹細胞の微分化の主要な調節体として作用し,系統の可能性を制限する.
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