The Role of Adseverin in RANKL-Induced Osteoclastogenesis : RANKL에 의해 유도되는 파골세포 형성에서의 adseverin의 역할

다국어 초록 (Multilingual Abstract)

Adseverin, a member of the gelsolin superfamily of actin binding proteins, is a Ca2+-dependent actin filament-severing protein. The role of adseverin has been reported about exocytosis regulation through actin cytoskeleton rearrangement in secretory cells. However, the function of adsevrin in bone still remains unclear, and it has not yet been examined in osteoclastogenesis.
Here, I investigated the role of adseverin in osteoclastogenesis using bone marrow-derived macrophages (BMMs). I found that expression of the adseverin gene, scinderin, was up-regulated during RANKL-induced osteoclast differentiation. Knock-down of adseverin significantly blocked the increase of nuclear factor of activated T cell c1 (NFATc1), which is a key regulator of osteoclastogenesis and also decreased the number of tartrate-resistant acid phosphatase (TRAP)-positive multinuclear cells (MNCs). In addition, adseverin deficiency impaired the resorption activity and the secretion of bone degrading enzymes in osteoclast. These phenomenons were caused by decreased NFATc1 expression through NF-B signaling.
Collectively, these findings indicate that adseverin plays an important role in osteoclastogenesis via regulation of NFATc1 expression.

목차 (Table of Contents)

• CONTENTS
• ABSTRACT i
• CONTENTS iii
• LIST OF FIGURES v
• I. Introduction 1
• II. Materials and Methods 4
• 1. Reagents and antibodies 4
• 2. Culture of osteoclast 4
• 3. TRAP staining and counting of osteoclast 5
• 4. Gene knock-down by small interfering RNAs (siRNAs) 5
• 5. Reverse transcription-polymerase chain reaction (RT-PCR) 6
• 6. Quantitative real-time PCR 6
• 7. Nuclear fractionation and preparation of protein lysate 7
• 8. Resorption assay 8
• 9. Immunocytochemistry 8
• 10. Cell proliferation assay (CCK assay) 9
• 11. Western blot 9
• 12. MMP assay 10
• 13. Statistical analysis 10
• III. Results 11
• 1. Adseverin expression is upregulated in RANKL-induced osteocalstogenesis 11
• 2. Osteoclasf differentation in adseverin knock-downed BMMs 13
• 3. Adseverin affects resorption activity of osteoclasts 15
• 4. Effect on actin ring formation and localization of adseverin 17
• 5. Adseverin does not affect the proliferation of BMMs 19
• 6. Adseverin controls expression of NFATc1 which is the key
• regulator of osteoclastogenesis 21
• 7. Adseverin regulates osteoclastogenesis via NF-kB signaling, not
• MAPKs 26
• 8. Enzyme secretion in adseverin-depleted osteoclasts 28
• IV. Discussion 32
• V. References 35
• ABSTRACT IN KOREAN 39