Jun-FosとビタミンAとDの受容体は,ヒトのオステオカルシン遺伝子の共通の反応要素を認識しています
R Schüle1, K Umesono, D J Mangelsdorf
1Howard Hughes Medical Institute, Salk Institute, La Jolla, California 92037.
Cell
|May 4, 1990
まとめ
オステオカルシン遺伝子のビタミンD反応要素は,レチノ酸にも反応する. この転写因子の交叉結合は,ビタミンAとビタミンDによる遺伝子調節に関する新しい洞察を明らかにします.
科学分野:
- 分子生物学は分子生物学である.
- 遺伝子規制 遺伝子規制
- エンドクリノロジー エンドクリノロジー
背景:
- 人間のオステオカルシン遺伝子は,ビタミンD応答要素 (VDRE) を含んでいます.
- ビタミンDとレチノ酸は,様々な細胞プロセスに関与する重要なシグナル伝達分子です.
研究 の 目的:
- レチノ酸反応を媒介するVDREの役割を調査する.
- オステオカルシン遺伝子発現の調節に関与する転写因子を特定する.
主な方法:
- バクテリア発現レチノ酸受容体 (RAR) を用いたインビトロ結合アッセイ.
- 培養細胞におけるRAR発現ベクトルの転移を含むインビボ研究.
- Jun-Fos複合体とAP-1サイト相互作用の分析と共伝染の効果.
主要な成果:
- VDREは,レチノ酸に対する反応性を与え,クロスカップリングを証明します.
- レチノ酸受容体 (RAR) は,in vitroでVDRE配列に結合する.
- JunとFosとのコトランスフィクションは,基礎代写を抑制し,レチノ酸とビタミンD3による転写を誘導した.
結論:
- 異なった転写因子クラスは,共通の規制配列 (クロスカップリング) を認識することができます.
- VDRE内のAP-1サイトは,複数の要因のためにコア認識サイトです.
- この発見は,ビタミンAとビタミンDのシグナル伝達経路のクロストークに関する新しい洞察を提供します.
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