RANKLは,インターフェロンベータのc-Fos依存誘導により,骨の恒常性を維持する
Hiroshi Takayanagi1, Sunhwa Kim, Koichi Matsuo
1Department of Immunology, Faculty of Medicine and Graduate School of Medicine, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033, Japan.
Nature
|April 19, 2002
まとめ
NF-kappaBリガンド (RANKL) の受容体活性化剤は,骨格細胞の前駆体におけるインターフェロン-β (IFN-β) を誘導する. このIFN-βは,骨格細胞の分化を阻害し,骨の恒常性のための新しい調節経路を明らかにします.
科学分野:
- 細胞生物学 細胞生物学
- 免疫学 免疫学とは
- 骨の生物学 骨の生物学
背景:
- モノサイト/マクロファージから派生した骨格細胞は,骨の再吸収に不可欠です.
- RANKL (NF-kappaBリガンドの受容体活性化剤) 信号伝達は,骨格細胞の分化と骨の恒常性のために不可欠である.
- RANKLシグナリングを細胞内経路と結びつける規制メカニズムは,依然としてほとんど不明である.
研究 の 目的:
- オステオクラストの分化におけるRANKL信号伝達の潜在的な細胞内調節機構を調査する.
- RANKL誘発の骨格形成におけるインターフェロン-β (IFN-β) の役割を明らかにする.
主な方法:
- オステオクラスト前駆細胞における遺伝子発現の分析.
- RANKL誘発の微分化に対するIFN-βの影響を調査する.
- IFN-βシグナル伝達に欠陥があるマウスモデルを使用.
主要な成果:
- RANKLは,オステオクラスト前駆細胞のインターフェロン-β (IFN-β) 遺伝子を誘導する.
- IFN-βは,重要な転写因子であるc-Fos発現に干渉することによって,骨格細胞の分化を抑制する.
- IFN-β誘導はc-Fosに依存しており,自己調節ループを示しています.
- IFN-βシグナル伝達が欠けているマウスは,骨格不全と骨格結晶生成の増加を示しています.
結論:
- RANKLが誘導するc-Fosが自身の阻害体であるIFN-βを上調する新しい自己調節メカニズムが存在します.
- このIFN-β媒介経路は,骨の恒常性を維持するために重要である.
- この発見は,骨粗鬆症のような骨疾患の潜在的な治療目標を示唆しています.
関連する概念動画
Bone Remodeling
Bone remodeling is a continuous and balanced process of bone resorption by osteoclasts and bone formation by osteoblasts. In adults, it helps maintain bone mass and calcium homeostasis. While mechanical stress can stimulate turnover as part of the normal maintenance and reparative process, several hormones also regulate bone remodeling.
NF-κB-dependent Signaling Pathway
The transcription factor NF-κB was discovered in 1986 in the lab of Nobel laureate Professor David Baltimore, for its interaction with the immunoglobulin light chain enhancer in B-cells. After more than three decades of study, it is now evident that NF-κB regulates the expression of over 100 genes. Most of these genes play an essential role in the innate and adaptive immune responses as well as the inflammatory responses of animals.
NF-κB-dependent Signaling Mechanism
The heterodimer of NF-κB...
NF-κB-dependent Signaling Mechanism
The heterodimer of NF-κB...
Osteoclasts in Bone Remodeling
Osteoclasts are cells responsible for bone resorption and remodeling. They originate from hematopoietic progenitor cells present in the bone marrow. Numerous progenitor cells fuse to form multinucleated cells, each with 10-20 nuclei. A single osteoclast has a diameter of 150 to 200 µM. These cells have ruffled borders that break down the underlying bone tissue and release minerals such as calcium into the blood in bone resorption. Osteoclasts cling to bones with their ruffled edges during bone...
Hormones and Bone Tissue
The endocrine system produces and secretes hormones, which interact with the skeletal system. These hormones control bone growth, maintain bone once it is formed, and remodel it.
Hormones That Influence Osteoblasts and/or Maintain the Matrix
Several hormones are necessary for controlling bone growth and maintaining the bone matrix. The pituitary gland secretes growth hormone (GH), which, as its name implies, controls bone growth. This happens in several ways: first, it triggers chondrocyte...
Hormones That Influence Osteoblasts and/or Maintain the Matrix
Several hormones are necessary for controlling bone growth and maintaining the bone matrix. The pituitary gland secretes growth hormone (GH), which, as its name implies, controls bone growth. This happens in several ways: first, it triggers chondrocyte...
Skeleton and Calcium Homeostasis
Calcium is not only the most abundant mineral in bone but also the most abundant mineral in the human body. Calcium ions are needed for bone mineralization, tooth health, heart rate regulation and strength of contraction, blood coagulation, the contraction of smooth and skeletal muscle cells, and the regulation of nerve impulse conduction. The average calcium level in the blood is about 10 mg/dL. When the body cannot maintain this level, a person will experience hypo or hypercalcemia.
Bone Remodeling and Repair
Osteoclasts are cells responsible for bone resorption and remodeling. They originate from hematopoietic progenitor cells present in the bone marrow. Numerous progenitor cells fuse to form multinucleated cells, each with 10-20 nuclei. A single osteoclast has a diameter of 150 to 200 µM. These cells have ruffled borders that break down the underlying bone tissue and release minerals such as calcium into the blood in bone resorption. Osteoclasts cling to bones with their ruffled edges during bone...


