Xenopus borealis oocyte 5S DNAのヌクレオチド配列:いくつかの関連する真核生物遺伝子を横断する配列の比較
Cell
|December 1, 1978
まとめ
Xenopus borealis 5S DNAのゲノム解析により,変数の遺伝子番号とAT豊富なスペーサーを持つ遺伝子クラスターが明らかになりました. 保存されたオリゴヌクレオチドを含むプロモーター要素は,RNAポリメラーゼIIIによる転写を駆動する.
科学分野:
- 分子生物学は分子生物学である.
- ゲノミクスゲノミクスとは
- 発達生物学 発達生物学とは
背景:
- ゲノムXenopus borealisの卵細胞特異5SDNA (Xbo) は,5SrRNA遺伝子のクラスタを特徴とし,遺伝子番号とAT豊富なスペーサーが異なる.
- スペーサーDNAの長さの異質性は,部分的に並列で繰り返される配列によるものです.
研究 の 目的:
- Xenopus borealis 5S rRNA遺伝子のゲノム組織と転写制御の特徴を明らかにする.
- RNAポリメラーゼIIIの転写に関与する保存されたプロモーター要素を特定する.
主な方法:
- クローンされたXbo 5SのDNA断片 (Xbo1) のDNA配列解析.
- ゲノムDNAと隣接する領域の配列解析.
- Xenopus laevisの卵細胞核抽出物を用いたインビトロ転写アッセイ.
主要な成果:
- Xbo1には3つの5SrRNA遺伝子が含まれており,3番目の遺伝子は重要な配列の分岐を示していますが,豊富な成分です.
- 各5S遺伝子の前の80個の核酸は,インビトロにおいてプロモーター機能に十分である.
- 5'側面領域の保存されたオリゴヌクレオチド (AAAAG,AGAAG,GAC) は,RNAポリメラーゼIII転写の主要なプロモーター要素として機能する.
- 3'側面の領域は,GC豊富なダイアド対称性およびAT豊富なTクラスターを含む,プロカリオート転写終末部位に類似した特徴を示しています.
結論:
- Xenopus 5S遺伝子の5'側面配列には,転写を開始するための重要なプロモーター要素が含まれています.
- プロモーター領域における配列保存は,スペーサーDNAの変異にもかかわらず,それらの機能的重要性を強調します.
- 特定されたプロモーターおよび終止信号は,Xenopus.で5SrRNA遺伝子発現の調節に関する洞察を提供します.
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