Protective role of macroautophagy against oxidative stress-induced TDP-43 pathology
- 주제(키워드) amyotrophic lateral sclerosis , GABARAP , macroautophagy , oxidative stress , selective autophagy , TDP-43 , TDP-43 phosphorylation , TTBK2
- 주제(DDC) 570
- 발행기관 아주대학교 일반대학원
- 지도교수 Jaerak Chang
- 발행년도 2026
- 학위수여년월 2026. 8
- 학위명 석사
- 학과 및 전공 일반대학원 의생명과학과
- 실제URI http://www.dcollection.net/handler/ajou/000000036178
- 본문언어 영어
- 저작권 아주대학교 논문은 저작권에 의해 보호받습니다.
초록/요약
TAR DNA-binding protein 43 （TDP-43） proteinopathy, characterized by cytoplasmic mislocalization, aggregation, and hyperphosphorylated TDP-43, is a pathological hallmark of amyotrophic lateral sclerosis （ALS）. Various cellular stresses, including oxidative stress, mitochondrial dysfunction, and endoplasmic reticulum stress, have been implicated in the development of TDP-43 pathology. Among these, oxidative stress is considered a key pathogenic factor. In this study, I investigated the protective role of macroautophagy in regulating TDP-43 pathology under oxidative stress conditions. TDP-43 mislocalization, aggregation, and phosphorylation induced by H₂O₂ treatment were attenuated by induction of macroautophagy. This protective effect was mediated by enhanced degradation of Tau tubulin kinase 2 （TTBK2）, a kinase responsible for TDP-43 phosphorylation. I further found that TTBK2 is selectively degraded through GABARAP-mediated macroautophagy via GABARAP-interacting motif （GIM）. Collectively, these findings demonstrate that macroautophagy functions as a protective mechanism that suppresses oxidative stress-induced TDP-43 pathology by regulating TTBK2 abundance. These results suggest that enhancing autophagic activity may represent a potential therapeutic strategy for attenuating TDP-43 pathology in neurodegenerative diseases, including ALS.
more목차
I. BACKGROUND 1
1. Amyotrophic lateral sclerosis 1
2. Oxidative stress 4
3. TDP-43 proteinopathy 8
4. Macroautophagy 11
II. INTRODUCTION 16
III. MATERIALS AND METHODS 19
1. Cell culture 19
2. DNA constructs 19
3. Transfection 20
4. Generation of knockout cell lines 20
5. Generation of stable cell lines 21
6. Drug treatments 22
7. Cycloheximide chase assay 22
8. GST pull-down assay 22
9. Antibodies 23
10. Immunoblotting 23
11. Immunofluorescence 24
12. Tandem fluorescent assay 25
13. Quantification and image analysis 26
14. Statistical analysis 26
15. Generation of schematic illustrations 27
IV. RESULTS 32
1. Oxidative stress recapitulates key features of TDP-43 pathology 32
2. Macroautophagy induction prevents oxidative stress-induced TDP-43 mislocalization and aggregation 34
3. Macroautophagy suppresses TDP-43 phosphorylation under both oxidative stress and basal conditions 38
4. CK1δ and TTBK2 were identified as TDP-43 kinases undergoing macroautophagy-dependent degradation 43
5. CK1δ and TTBK2 undergo macroautophagy-dependent degradation in autophagy-deficient cells 49
6. GABARAP family proteins mediate selective macroautophagy of TTBK2 via a GABARAP-interacting motif 56
V. DISCUSSION 67
VI. REFERENCES 72
국문요약 87
