ドロソフィラの粘着タンパク質遺伝子にわずか5'を挿入したトランスポーザブル要素は,遺伝子発現とクロマチンの構造を変化させます
Cell
|August 1, 1983
まとめ
新しい移植可能な元素であるhoboは,ドロソフィラSgs-4の遺伝子調節を妨害する. この障害は,粘着タンパク質の産生を減らし,唾液腺における遺伝子発現パターンを変化させます.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
- 発達生物学 発達生物学とは
背景:
- ドロソフィラSgs-4遺伝子は,成熟した幼虫の粘着タンパク質の生産に不可欠です.
- Sgs-4の遺伝子発現は,DNAase Iの消化に敏感な遠隔の上流領域によって調節されます.
研究 の 目的:
- Sgs-4遺伝子発現と調節に対するDNA挿入の影響を調査する.
- 転置可能な元素の新しいファミリーを特徴付けるため,hobo. と呼ばれる.
主な方法:
- 1.3kBのDNA挿入を含むSgs-4変異体の分析.
- DNAase I過敏性アッセイは,規制領域をマップする.
- Sgs-4遺伝子製品を識別するための転写分析.
主要な成果:
- Sgs-4遺伝子とその遠隔の調節領域の間に,hoboトランスポーザブル要素として識別された1.3kbのDNA挿入が見つかりました.
- 変種Sgs-4ロカスの発現は50~100倍減少した.
- バリアントロカスから4つのトランスクリプトが検出され,その2つはホボエレメント内で開始され,単一の正規トランスクリプトとは異なり.
- 変異したトランスクリプト開始部位にもかかわらず,発達調節は後期幼虫の唾液腺に特異的であり続けました.
- 新しいDNAase I過敏性サイトは,ホボエレメント内で形成され,新しい転写開始サイトと相関しています.
結論:
- ホボ・トランスポーザブル・エレメントは,遺伝子発現を大幅に妨害し,転写パターンを変化させる可能性があります.
- トランスクリプト開始の変化にもかかわらず,Sgs-4の発達調節は不変のままです.
- この研究は,移植可能な元素と遺伝子発現に関連した新しい規制メカニズムを特定しています.
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