オバルブミン遺伝子の構造および中間配列からのRNAトランスクリプトの分布
まとめ
オバルブミン遺伝子の介入配列は転写されるが,細胞質に効率的に輸送されない. これは,これらの配列が遺伝子調節におけるタンパク質のコーディングを超えた役割を果たしていることを示唆しています.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝子発現の規制について
- ユカリオットの遺伝子構造 ユカリオットの遺伝子構造
背景:
- ユカリオットのオバルブミン遺伝子は,RNA処理中に除去される中間配列 (イントロン) を含んでいます.
- これらの中間配列とそのトランスクリプトの正確な機能は,依然として調査の分野です.
研究 の 目的:
- オバルブミン遺伝子の中間配列から派生したトランスクリプトの機能と細胞の局所化を調査する.
- 中間配列トランスクリプトの分布を成熟したメッセンジャーRNA (mRNA) のトランスクリプトと比較する.
主な方法:
- オバルブミンの干渉配列に特異的な放射性ラベル付きDNAプローブの準備.
- 鶏の卵巣細胞 (全細胞,核,ポリソーム) からRNAを分離する.
- クローンDNAプローブによるハイブリダイゼーションアッセイを用いたRNAトランスクリプトの定量化.
主要な成果:
- 卵管細胞には,約58,000個の卵白素構造配列mRNA (mRNAov) 分子が含まれており,主に細胞プラズマに存在します.
- 細胞ごとに300個未満のRNA分子が,卵白素の干渉配列から転写されます.
- これらの中間配列トランスクリプトは,ほぼ独占的に核内に局所されています.
結論:
- 構造的および間接的なシーケンスのトランスクリプトの異なる局所化は,異なる処理経路を示しています.
- 介入シーケンスのトランスクリプトは,優先的に細胞質ポリソームに輸送されず,成熟したmRNAとして機能しないことを示唆しています.
- これは,中断配列またはそれらのトランスクリプトの制御作用を,タンパク質のコーディングとは別に意味しています.
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