まとめ
アデノシントリフォスファート (ATP) の枯渇により,グルココルチコイド受容体が不活性な,不活性な領域に入ります.
科学分野:
- 細胞生物学 細胞生物学
- 分子内分泌学は分子内分泌学である.
- バイオケミストリー バイオケミストリー
背景:
- グルココルチコイド受容体 (GR) 結合は,グルココルチコイドに対する細胞応答に不可欠です.
- 細胞内のATPの枯渇は,GR結合能力の喪失につながります.
- ATPが枯渇した細胞の無活性な"無受容体"形態の存在は仮定されたが,直接観察されなかった.
研究 の 目的:
- ゼロ受容体の存在に対する直接的な証拠を提供すること.
- ATPが枯渇した細胞におけるヌル受容体の局所化と豊富性を調査する.
主な方法:
- マウスチモーマ細胞 WEHI-7 を利用した.
- グルココルチコイド受容体に特異的なモノクローナル抗体を用いる.
- 評価された受容体の局所化と結合は,正常な状態とATP不足の細胞状態の両方で評価されました.
主要な成果:
- ゼロ受容体は,ATPが枯渇した細胞の核で検出されました.
- ATPが枯渇した細胞のヌル受容体の量は,正常な細胞の受容体の量と同等であった.
- これは,受容体が存在するが,不活性で結合しない形状であることを示唆する.
結論:
- 直接的に,グルココルチコイド受容体の不活性な形態であるヌル受容体の存在を証明する.
- ヌル受容体は核内に局所され,ホルモン結合が失われても,かなりの量に存在します.
- この発見は,ATPレベルがグルココルチコイド受容体の活性ホルモン結合状態を調節するモデルを支持する.
関連する概念動画
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Similar to membrane-bound receptors, the binding of a ligand to the intracellular receptor of causes a conformational change in the...
Similar to membrane-bound receptors, the binding of a ligand to the intracellular receptor of causes a conformational change in the...
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Two...
Two...
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About 48 different soluble family members of nuclear receptors are identified that can be divided into two main classes:
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Notably, the cellular response can be regulated by altering the number of receptors expressed in the cell. For example, prolonged exposure to elevated hormone levels results in a gradual decline or down-regulation in the number of receptors for that specific hormone on the cell surface. Conversely, in response to low hormone levels, cells may use up-regulation, producing an...
Notably, the cellular response can be regulated by altering the number of receptors expressed in the cell. For example, prolonged exposure to elevated hormone levels results in a gradual decline or down-regulation in the number of receptors for that specific hormone on the cell surface. Conversely, in response to low hormone levels, cells may use up-regulation, producing an...


