転写的に静かな遺伝子のイカロス複合体との関連は,セントロメリックヘテロクロマチンのイカロス複合体である
K E Brown1, S S Guest, S T Smale
1Lymphocyte Development Group, MRC Clinical Sciences Centre, Imperial College School of Medicine, Hammersmith Hospital, London, United Kingdom.
Cell
|December 31, 1997
まとめ
免疫細胞の発達に不可欠なイカロスタンパク質は,予想外にもB細胞の濃厚なDNA領域に結合します. これは,抑圧された遺伝子がこれらの核区画の中に組織されていることを示唆しています.
科学分野:
- 細胞生物学 細胞生物学
- 免疫学 免疫学とは
- 遺伝学 遺伝学とは
背景:
- イカロスタンパク質は,T,B,NK細胞の発達に不可欠です.
- リンパ球特異遺伝子発現を活性化すると考えられています.
- イカロスタンパク質の核の位置と機能は,まだ完全に理解されていない.
研究 の 目的:
- Bリンパ球におけるイカロスタンパク質の核分布を調査する.
- イカロスの特定の核構造と遺伝子位置との関連を決定する.
主な方法:
- コンフォカル顕微鏡を用いて,イカロスタンパク質の局所化を視覚化しました.
- 新しい免疫光 in situ ハイブリダイゼーション (免疫-FISH) テクニックが開発され,利用されました.
- ロカス特有の探査機を使用して,イカロス焦点との遺伝子関連性を調べました.
主要な成果:
- イカロスタンパク質は,Bリンパ球核の異性染色体を含む離散的焦点に意外と局所化した.
- これらの焦点は,ヘテロクロマチンタンパク質-1 (HP-1) に富んだセントロメリックDNAのクラスターとして識別されました.
- 転写的に不活性な遺伝子 (CD2,CD4,CD8alpha,CD19,CD45,lambda5) はイカロス・ヘテロクロマチン焦点と関連しているが,活性な遺伝子は関連していない.
結論:
- イカロスタンパク質は,核内のセントロメリックヘテロクロマチン領域に採用されます.
- この局所化は,Ikarosが特定の核コンパートメント内の抑圧された遺伝子を組織する役割を持っていることを示唆しています.
- この発見は,核が抑圧された遺伝子をセンターメリックドメインに編成するモデルを支持する.
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The extent of chromatin compaction can be studied by staining chromatin using specific DNA binding dyes. Under the microscope, the dense-compacted regions take up more dye, appearing darker, while the less-compact areas take up less dye and appear lighter. Based on the compaction level, chromatins are classified into two primary forms – euchromatin and heterochromatin.
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