簡易檢索 / 詳目顯示

回結果列表
研究生： 林言叡
Lin, Yan-Rui
論文名稱： 自噬相關基因 Beclin 1/atg6 在tauopathy的果蠅中調控磷酸化 tau 蛋白情形
The autophagy-related gene, Beclin 1/atg6, regulates the phosphorylated tau protein for tauopathy in Drosophila
指導教授： 張慧雲
Chang, Hui-Yun
口試委員: 羅中泉
Lo, Chung-Chuan
陳俊宏
Chen, Chun-Hong
學位類別： 碩士
Master
系所名稱： 生命科學暨醫學院 - 系統神經科學研究所
Institute of Systems Neuroscience
論文出版年： 2022
畢業學年度： 110
語文別： 英文
論文頁數： 47
中文關鍵詞： 自噬作用 、atg6 、tau 蛋白 、阿茲海默症 、神經退化疾病
外文關鍵詞： autophagy, atg6, tau protein, Alzheimer's disease, Neurodegenerative diseases
相關次數： 點閱：3  下載：0 
分享至:
查詢本校圖書館目錄 查詢臺灣博碩士論文知識加值系統 勘誤回報

    • Alzheimer's disease (AD）是一種常見的神經退行性疾病，屬於繼發性Tauopathy的一種。一般來說，AD可分為早發性和晚發性，通常以65歲為分水嶺，通常晚發性AD約佔整體病患的90%，因此多發生於高齡長者。目前，科學界推斷引起這類Tauopathy 症狀其中一種可能的原因是當神經細胞中的神經細胞微管相關蛋白tau被過度磷酸化成異常斑塊和神經纖維糾結纏繞(NFT)所導致，這會增加神經細胞內的毒素導致神經細胞大量壞死，並導致神經細胞與神經細胞之間形成的突觸破壞和神經細胞大量凋亡造成大腦永久性損傷。而在分子生物學方面，自噬作用涉及異常蛋白、受損胞器等的降解與回收。而Atg6對於誘導自噬作用的啟動至關重要，本實驗將重點關注在通過對自噬相關蛋白Atg6的調控來觀察對於果蠅眼中異常磷酸化tau蛋白的表達之影響。我們將使用GAL4-UAS轉基因系統觀察Atg6相關轉基因對過磷酸化tau果蠅模型的影響。我們的結果發現當atg6強烈抑制時，可以改善過度磷酸化tau誘導的表型，表明改變Atg6的表達可能會改變tau誘導的神經退化性變性與tau異常聚集情形。反之，強化阻斷Atg6在成核起始作用的表現可以有效延遲tau的傳播途徑的發生，使敲除atg6的果蠅發生更嚴重的磷酸化tau表現。
    由此，我們認為透過Atg6調控自噬作用的表現對於tau過磷酸化時所產生的NFT神經元內聚集體的降解具有一定程度的作用，可有效改善tau誘導的神經退化性變性表型與tau異常聚集的情形。

    Alzheimer's disease (AD) is a common neurodegenerative disease, which is a secondary tauopathy. AD can be divided into early-onset and late-onset, it divides at the age of 65. Late-onset AD accounts for about 90% of the total patients, so it mostly occurs in the elderly. At present, the scientific community speculates that one of the possible causes of tauopathy is when the nerve cell microtubule-associated protein tau protein in neuron cells is hyperphosphorylated into abnormal plaques and nerve fiber tangles (NFTs), which increases the toxins level in nerve cells and lead to massive nerve cell death. It also can lead to the destruction of synapses formed between nerve cells and the massive apoptosis of nerve cells, resulting in permanent brain damage. In molecular biology, autophagy involves the degradation and recovery of abnormal proteins and damaged organelles. Atg6 is essential for the initiation of autophagy induction. Our experiment will focus on the regulation of autophagy-related protein Atg6 on the expression of abnormally phosphorylated tau protein in Drosophila eyes. We use Gal4-UAS transgenic system to observe the effect of atg6-related transgene on the hyperphosphorylated tau in Drosophila. Our results showed that when Atg6 was strongly inhibited, the hyperphosphorylation tau-induced phenotype could be improved, indicating that changing the expression of Atg6 might change the tau-induced neurodegeneration and tau abnormal aggregation. Conversely, knockdown Atg6 expression in autophagy nucleation initiation can effectively delay the tau propagation pathways. Therefore, we believe that the regulation of autophagy with Atg6 has a certain extent the degradation of aggregates in NFT neurons generated during Tau hyperphosphorylation, which can effectively improve the tau-induced neurodegenerative phenotype and tau abnormal aggregation.

    摘要 1 Abstract 2 Acknowledgement 3 Introduction 6 1. Tauopathy 6 2. Alzheimer’s Disease (AD) 6 3. Autophagy 7 4. Neurodegenerative diseases in which autophagy is impaired 9 5. Beclin 1 9 6. Drosophila melanogaster 10 Methods and materials 11 1. Drosophila stocks and genetics 11 2. Drosophila eye dissection 12 3. Immunostaining 12 4. Zeiss LSM510 confocal microscope scanning 13 5. Drosophila eye in Scanning Electron Microscope (SEM) analysis 13 6. Statistical analysis 15 Result 16 Regulating Atg6 expression can affect the level of tau-induced phenotype in Drosophila compound eye 16 Autophagy-related Atg6 regulates the tau-induced retinal structure degeneration in Drosophila 17 Human tau-induced phenotype was rescued by autophagy-related Atg6 18 Atg6 signal mainly acts on the certain area in Drosophila eye. 19 Discussion 22 1. The Expression patterns of Atg6 in Drosophila eye 22 2. Vps34 knockdown could also cause retinal cell destruction and P-tau accumulation in Drosophila eye 23 Figures 25 Figure 1. Overview of initiation of autophagy activation 26 Figure 2. The protein structure domain of BECN1 28 Figure 3. Knockdown Atg6 enhanced the P-tau level in male Drosophila eye 30 Figure 4. Knockdown Atg6 enhanced the P-tau level in female Drosophila eye 33 Figure 5. Atg6 can reduce P-tau level in male Drosophila eye 36 Figure 6. Atg6 can reduce P-tau level in female Drosophila eye. 38 Figure 7. Regulating Atg6 expression can affect the phenotype of vision structure in Drosophila. 40 Figure 8. Atg6 regulation can affect the retinal cell structure of Drosophila eye. 41 Reference 42

    1. Irwin, D.J., Tauopathies as clinicopathological entities. Parkinsonism & related disorders, 2016. 22 Suppl 1(0 1): p. S29-S33.
    2. Medeiros, R., D. Baglietto-Vargas, and F.M. LaFerla, The role of tau in Alzheimer's disease and related disorders. CNS Neurosci Ther, 2011. 17(5): p. 514-24.
    3. Šimić, G., et al., Tau Protein Hyperphosphorylation and Aggregation in Alzheimer's Disease and Other Tauopathies, and Possible Neuroprotective Strategies. Biomolecules, 2016. 6(1): p. 6-6.
    4. Alonso, A.D., et al., Hyperphosphorylation of Tau Associates With Changes in Its Function Beyond Microtubule Stability. Frontiers in Cellular Neuroscience, 2018. 12.
    5. Livingston, G., et al., Dementia prevention, intervention, and care: 2020 report of the Lancet Commission. Lancet (London, England), 2020. 396(10248): p. 413-446.
    6. Qiu, C., et al., Prevention of cognitive decline in old age-varying effects of interventions in different populations. Annals of translational medicine, 2019. 7(Suppl 3): p. S142-S142.
    7. Sun, Y., et al., A nationwide survey of mild cognitive impairment and dementia, including very mild dementia, in Taiwan. PloS one, 2014. 9(6): p. e100303-e100303.
    8. Reitz, C., E. Rogaeva, and G.W. Beecham, Late-onset vs nonmendelian early-onset Alzheimer disease: A distinction without a difference? Neurology. Genetics, 2020. 6(5): p. e512-e512.
    9. Tarawneh, R. and D.M. Holtzman, The clinical problem of symptomatic Alzheimer disease and mild cognitive impairment. Cold Spring Harbor perspectives in medicine, 2012. 2(5): p. a006148-a006148.
    10. McAfee, Q., et al., Autophagy inhibitor Lys05 has single-agent antitumor activity and reproduces the phenotype of a genetic autophagy deficiency. Proceedings of the National Academy of Sciences of the United States of America, 2012. 109(21): p. 8253-8258.
    11. Kotiadis, V.W., M. Duchen, and L. Osellame, Mitochondrial quality control and communications with the nucleus are important in maintaining mitochondrial function and cell health. Biochimica et biophysica acta, 2013. 1840.
    12. Menzies, F.M., et al., Autophagy and Neurodegeneration: Pathogenic Mechanisms and Therapeutic Opportunities. Neuron, 2017. 93(5): p. 1015-1034.
    13. Hara, T., et al., Suppression of basal autophagy in neural cells causes neurodegenerative disease in mice. Nature, 2006. 441(7095): p. 885-889.
    14. Gorman, A.M., Neuronal cell death in neurodegenerative diseases: recurring themes around protein handling. J Cell Mol Med, 2008. 12(6a): p. 2263-80.
    15. Liu, J. and L. Li, Targeting Autophagy for the Treatment of Alzheimer's Disease: Challenges and Opportunities. Front Mol Neurosci, 2019. 12: p. 203.
    16. Wei, Y., et al., ERβ promotes Aβ degradation via the modulation of autophagy. Cell Death & Disease, 2019. 10(8): p. 565.
    17. Ries, M. and M. Sastre, Mechanisms of Aβ Clearance and Degradation by Glial Cells. Frontiers in Aging Neuroscience, 2016. 8.
    18. Nixon, R.A. and D.-S. Yang, Autophagy and neuronal cell death in neurological disorders. Cold Spring Harbor perspectives in biology, 2012. 4(10): p. a008839.
    19. Levine, B. and G. Kroemer, Biological Functions of Autophagy Genes: A Disease Perspective. Cell, 2019. 176(1): p. 11-42.
    20. Pickford, F., et al., The autophagy-related protein beclin 1 shows reduced expression in early Alzheimer disease and regulates amyloid beta accumulation in mice. J Clin Invest, 2008. 118(6): p. 2190-9.
    21. Venken, K.J., et al., Genome engineering: Drosophila melanogaster and beyond. Wiley Interdiscip Rev Dev Biol, 2016. 5(2): p. 233-67.
    22. Pandey, U.B. and C.D. Nichols, Human disease models in Drosophila melanogaster and the role of the fly in therapeutic drug discovery. Pharmacol Rev, 2011. 63(2): p. 411-36.
    23. Mirzoyan, Z., et al., Drosophila melanogaster: A Model Organism to Study Cancer. Front Genet, 2019. 10: p. 51.
    24. Morton, D.B., et al., Synaptic transmission in neurons that express the Drosophila atypical soluble guanylyl cyclases, Gyc-89Da and Gyc-89Db, is necessary for the successful completion of larval and adult ecdysis. J Exp Biol, 2008. 211(Pt 10): p. 1645-56.
    25. Lyons, L.C. and G. Roman, Circadian modulation of short-term memory in Drosophila. Learn Mem, 2009. 16(1): p. 19-27.
    26. Lu, B. and H. Vogel, Drosophila models of neurodegenerative diseases. Annu Rev Pathol, 2009. 4: p. 315-42.
    27. Anderson, K.I., et al., A new configuration of the Zeiss LSM 510 for simultaneous optical separation of green and red fluorescent protein pairs. Cytometry A, 2006. 69(8): p. 920-9.
    28. Iqbal, K., et al., Tau in Alzheimer disease and related tauopathies. Current Alzheimer research, 2010. 7(8): p. 656-664.
    29. Shravage, B.V., et al., Atg6 is required for multiple vesicle trafficking pathways and hematopoiesis in Drosophila. Development, 2013. 140(6): p. 1321-9.
    30. Shravage, B.V., et al., Atg6 is required for multiple vesicle trafficking pathways and hematopoiesis in Drosophila. Development (Cambridge, England), 2013. 140(6): p. 1321-1329.
    31. Nishihara, S., et al., Approach for functional analysis of glycan using RNA interference. Glycoconj J, 2004. 21(1-2): p. 63-8.
    32. Midorikawa, R., et al., Autophagy-dependent rhodopsin degradation prevents retinal degeneration in Drosophila. J Neurosci, 2010. 30(32): p. 10703-19.
    33. Cagan, R., Principles of Drosophila eye differentiation. Curr Top Dev Biol, 2009. 89: p. 115-35.
    34. Salcedo, E., et al., Blue- and green-absorbing visual pigments of Drosophila: ectopic expression and physiological characterization of the R8 photoreceptor cell-specific Rh5 and Rh6 rhodopsins. J Neurosci, 1999. 19(24): p. 10716-26.
    35. Song, B.M. and C.H. Lee, Toward a Mechanistic Understanding of Color Vision in Insects. Front Neural Circuits, 2018. 12: p. 16.
    36. Rangaraju, V., N. Calloway, and T.A. Ryan, Activity-driven local ATP synthesis is required for synaptic function. Cell, 2014. 156(4): p. 825-35.
    37. Harris, Julia J., R. Jolivet, and D. Attwell, Synaptic Energy Use and Supply. Neuron, 2012. 75(5): p. 762-777.
    38. Ziv, N.E., Maintaining the active zone: Demand, supply and disposal of core active zone proteins. Neuroscience Research, 2018. 127: p. 70-77.
    39. Bhukel, A., et al., Autophagy within the mushroom body protects from synapse aging in a non-cell autonomous manner. Nature Communications, 2019. 10(1): p. 1318.
    40. Rinetti, G.V. and F.E. Schweizer, Ubiquitination Acutely Regulates Presynaptic Neurotransmitter Release in Mammalian Neurons. The Journal of Neuroscience, 2010. 30(9): p. 3157-3166.
    41. Ciechanover, A. and Y.T. Kwon, Degradation of misfolded proteins in neurodegenerative diseases: therapeutic targets and strategies. Exp Mol Med, 2015. 47(3): p. e147.
    42. Zhang, L., L. Chen, and H. Dong, Plant Aquaporins in Infection by and Immunity Against Pathogens - A Critical Review. Frontiers in plant science, 2019. 10: p. 632-632.
    43. Ross, J., et al., Serine proteases and their homologs in the Drosophila melanogaster genome: an initial analysis of sequence conservation and phylogenetic relationships. Gene, 2003. 304: p. 117-31.
    44. Irizarry, M.C., et al., Abeta deposition is associated with neuropil changes, but not with overt neuronal loss in the human amyloid precursor protein V717F (PDAPP) transgenic mouse. J Neurosci, 1997. 17(18): p. 7053-9.
    45. Pickford, F., et al., The autophagy-related protein beclin 1 shows reduced expression in early Alzheimer disease and regulates amyloid beta accumulation in mice. The Journal of clinical investigation, 2008. 118(6): p. 2190-2199.
    46. Pérez-Pérez, J.M., H. Candela, and J.L. Micol, Understanding synergy in genetic interactions. Trends in Genetics, 2009. 25(8): p. 368-376.
    47. 2013 Alzheimer's disease facts and figures. Alzheimers Dement, 2013. 9(2): p. 208-45.
    48. Beam, C.R., et al., Differences Between Women and Men in Incidence Rates of Dementia and Alzheimer's Disease. Journal of Alzheimer's disease : JAD, 2018. 64(4): p. 1077-1083.
    49. Shokouhi, S., et al., In vivo network models identify sex differences in the spread of tau pathology across the brain. Alzheimers Dement (Amst), 2020. 12(1): p. e12016.
    50. Shokouhi, S., et al., In vivo network models identify sex differences in the spread of tau pathology across the brain. Alzheimer's & dementia (Amsterdam, Netherlands), 2020. 12(1): p. e12016-e12016.
    51. Funderburk, S.F., Q.J. Wang, and Z. Yue, The Beclin 1-VPS34 complex--at the crossroads of autophagy and beyond. Trends Cell Biol, 2010. 20(6): p. 355-62.
    52. Kang, R., et al., The Beclin 1 network regulates autophagy and apoptosis. Cell Death Differ, 2011. 18(4): p. 571-80.
    53. Jiang, S. and K. Bhaskar, Degradation and Transmission of Tau by Autophagic-Endolysosomal Networks and Potential Therapeutic Targets for Tauopathy. Front Mol Neurosci, 2020. 13: p. 586731.
    54. Decuypere, J.P., J.B. Parys, and G. Bultynck, Regulation of the autophagic bcl-2/beclin 1 interaction. Cells, 2012. 1(3): p. 284-312.
    55. Hurley, J.H. and L.N. Young, Mechanisms of Autophagy Initiation. Annu Rev Biochem, 2017. 86: p. 225-244.
    56. Menon, M.B. and S. Dhamija, Beclin 1 Phosphorylation - at the Center of Autophagy Regulation. Front Cell Dev Biol, 2018. 6: p. 137.
    57. Oberstein, A., P.D. Jeffrey, and Y. Shi, Crystal structure of the Bcl-XL-Beclin 1 peptide complex: Beclin 1 is a novel BH3-only protein. J Biol Chem, 2007. 282(17): p. 13123-32.
    58. Ashkenazi, A., et al., Polyglutamine tracts regulate beclin 1-dependent autophagy. Nature, 2017. 545(7652): p. 108-111.
    59. Cao, Y. and D.J. Klionsky, Physiological functions of Atg6/Beclin 1: a unique autophagy-related protein. Cell Research, 2007. 17(10): p. 839-849.

    QR CODE