転写の方向に反するメオティック遺伝子変換グラデント
R E Malone1, S Bullard, S Lundquist
1Department of Biology, University of Iowa, Iowa City 52242.
Nature
|September 10, 1992
まとめ
Saccharomyces cerevisiaeの遺伝子変換は極性を示し,HIS2遺伝子の3'端でより高い頻度を示しています. これは,中性再結合の開始部位が遺伝子の場所に位置していない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.
- 遺伝学 遺伝学とは
- イースト遺伝学 イースト遺伝学
背景:
- 遺伝的再結合には,クロスオーバーと遺伝子変換 (異常分離) が含まれる.
- 酵母 (Saccharomyces cerevisiae) の遺伝子変換により,メンデルのような 3:1 または 1:3 の異種分離が生じます.
- 遺伝子の変換は極性,遺伝子の周波数のグラデーションを示します.
研究 の 目的:
- Saccharomyces cerevisiaeのHIS2遺伝子に対する遺伝子変換の極性を調査する.
- 変換極性に基づいて,メオティック再結合開始部位の位置を決定する.
主な方法:
- Saccharomyces cerevisiaeにおける胞子分離パターンの分析.
- HIS2遺伝子全体の遺伝子変換周波数グラディエントのマッピング.
主要な成果:
- HIS2遺伝子は,遺伝子変換のための極性グラデントを示しています.
- 遺伝子変換の最も高い頻度は,HIS2遺伝子の3'端で観察されています.
結論:
- 観測された極性は,中性再結合の開始部位が,HIS2遺伝子の3'端に位置することを示唆しています.
- HIS2遺伝子のプロモーター領域は,中性再結合の開始部位ではありません.
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