let-7ヘテロクロニックの規制RNAの配列と時間表現の保存
A E Pasquinelli1, B J Reinhart, F Slack
1Department of Molecular Biology, Massachusetts General Hospital, Harvard Medical School, Boston 02114, USA.
Nature
|November 18, 2000
まとめ
let-7小RNAは,多くの動物種における発達タイミングを調節する. このマイクロRNAは,脊椎動物と無脊椎動物に保存され,発達期の遅い移行を制御します.
科学分野:
- 発達生物学 発達生物学について
- 分子生物学は分子生物学である.
- 遺伝学 遺伝学とは
背景:
- *C. elegans*の発達タイミングは,lin-4とlet-7を含む小さなRNAによって調節されます.
- lin-4とlet-7RNAは,タンパク質をコードする遺伝子を標的にし,その発現を否定的に調節する.
- これらのRNAは同類ではないが,規制メカニズムを共有している.
研究 の 目的:
- let-7 RNAの進化的保存を調査するために.
- Let-7 RNAが様々な動物種における発達タイミングに作用するかどうかを判断する.
- 様々な分類におけるlet-7とlin-4RNAの存在を比較する.
主な方法:
- 様々な動物種からRNAを抽出する.
- 分子技術を用いた小さなRNAの検出.
- let-7 RNA発現タイミングの比較分析.
主要な成果:
- let-7 RNAs (約) (レット-7 RNAs) は,レット-7 RNAs (約) と呼ばれている. 21の核酸) は,脊椎動物,アシディアン,ヘミコルダ,軟体動物,アネリド,節足類で検出されました.
- lin-4 RNAは,試験した種のうちのいずれにも検出されなかった.
- let-7RNA発現のタイミングは保たれ, *C. elegans* と *Drosophila* の幼虫期の末期に現れ,アネリドと軟体動物では成人期に現れる.
結論:
- let-7 調節RNAは,幅広い動物群にわたって進化的に保存されています.
- let-7 RNAは,動物の系統形成全体を通して,発達期の遅い移行を制御している可能性が高い.
- 他の種におけるリン-4RNAの欠如は,ネマトードにおけるより具体的な役割を示唆する.
キーワード:
非プログラム的なものです.関連する概念動画
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