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Preparation of Drosophila Polytene Chromosome Squashes for Antibody Labeling
Published on: February 9, 2010
Drosophila puff lociで,ポリアドプリボゼポリメラーゼ (PARP) によってクロマチンの解き放たれが行われる
Alexei Tulin1, Allan Spradling
1Howard Hughes Medical Research Laboratories, Embryology Department, Carnegie Institution of Washington, 115 West University Parkway, Baltimore, MD 21210, USA.
まとめ
Poly ((ADP) - リボースポリメラーゼ (PARP) の活動は,ドロソフィラの遺伝子誘導を可能にする緩んだクロマチンの構造であるパフを作成するために不可欠です. PARPは,発達中のクロマチンを改変することによって,熱ショック遺伝子Hsp70の発現を調節するのに役立ちます.
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
- クロマチンの生物学
背景:
- 熱ショックタンパク質70 (Hsp70) のようなステロイドおよびストレス活性化遺伝子は,遺伝子発現を通じて誘発されます.
- ドロソフィラのポリテン染色体における遺伝子誘導は,膨らんだ染色体領域と関連しています.
- ポリテンの染色体パフは,染色体構造の局所的な解密を意味します.
研究 の 目的:
- プフの形成と遺伝子誘導におけるポリアドプリボゼポリメラーゼ (PARP) の役割を調査する.
- ストレス反応中のクロマチンの改造におけるアデノシン・ディフォスファート (ADP) - リボースの改変の関与を決定する.
主な方法:
- ドロソフィラ幼虫の唾液腺におけるパフ形成の分析.
- アデノシン・ディフォスファート (ADP) -リボース改変タンパク質の定量化.
- 熱ショック後の野生型およびPARP欠乏のドロソフィラのHsp70遺伝子発現とパフサイズ評価.
主要な成果:
- 遺伝子誘導の部位であるパフには,ADP-リボース改変タンパク質のレベルが高く蓄積されます.
- ポリアドプリボゼポリメラーゼ (PARP) は,通常のサイズのパフの形成に不可欠です.
- PARP欠乏症は,熱にさらされた後のHsp70発現の低下と異常な膨らみ構造につながる.
結論:
- 発達的または環境的なシグナルによって誘発される染色体PARPの活性化は,DNAに結合したタンパク質を除去することによって,膨らみ形成を促進することを提案されています.
- PARPによるこの局所的なクロマチンの緩解は,遺伝子転写とタンパク質の修飾のためのアクセシビリティを高める可能性があります.
- PARP媒介のクロマチンの改造は,発達とストレス反応の遺伝子調節における重要なメカニズムです.
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