2011-08-012024-05-13https://scholars.lib.ntu.edu.tw/handle/123456789/647300摘要：亨丁頓舞蹈症是一種晚發性的神經退化性疾病。它是由於huntingtin基因的第一個 外顯子的位置有三核普酸重複序列CAG的不正常擴大，導致產生由一串glutamine所組 成的蛋白質(胜肽)poly(Q)。Poly(Q)在腦部基底核的細胞中形成aggregation，導致細胞的 死亡。最近熱休克蛋白(heat shock protein, HSP)或又稱作chaperone被發現可以影響到 aggregation的形成。其中最有趣的是small HSP，比如人類的Hsp27以及小鼠的Hsp25 除了可以抵擋熱休克以及氧化壓力外，還可以減低細胞的凋亡apoptosis。在表現poly(Q) 的細胞中，Hsp27的表現也比較低。Hsp27可以在三個serine的位置被MAPKAP kinase 2/3鄰酸化。我們以前曾經將 Hsp27的serine變成aspartate，這樣的Hsp27-S3D功能上很像碟酸化的蛋白。我們證明 Hsp27-S3D可以有效的降低細胞中由poly(Q)所形成的aggregation。我們接著製作了 Hsp27-S3D的基因轉殖小鼠。這樣的小鼠在外觀上是正常的，可是或許是因為生殖細胞 的毒性，轉殖基因無法傳遞到下一代，因此我們無法進行實驗。在這個計晝中，我們將使用病毒載體在亨丁頓舞蹈症小鼠R6/2的腦部表現 Hsp27-S3D來進行治療。我們將使用AAV1病毒載體來進行研究，因為AAV1曾經被證 實可以在腦部產生廣泛性的表現。我們將利用腦部立體定位手術，將病毒載體注射到小 鼠腦部，並且可以用表現GFP的AAV1載體來證明表現的位置及範圍。4-6週的R6/2 小鼠經過治療後我們將用Rotarod以及grasping來追蹤治療的效果，最後的組織學分析 則將告物我們aggregation以及細胞低凋亡的狀態。這個計晝將可以告訴我們是否可以為 poly(Q)疾病開發一個新的治療。這個計晝也將協助我們了解poly(Q)疾病的致病機轉。<br> Abstract: Huntington’s disease (HD) is a late-onset neurodegenerative disease characterized byintranuclear and cytoplasmic aggregates and cell death in the striatal region. HD is caused byabnormal expansion of the trinucleotide (CAG) repeat sequence in exon 1 of the gene (Htt)encoding the huntingtin protein. Recently, heat shock proteins are identified as potentialmodulators of poly(Q) aggregation and/or cell death. More interestingly, the small heat shockproteins (sHsps) from human (Hsp27) and mouse (Hsp25) protect cells from heat shock andoxidative stress, and decrease apoptosis. Cells with expanded poly(Q) revealed reducedprotein expression of HSP27.Hsp27 is rapidly phosphorylated by MAPKAP kinase 2/3 at three serine residues. Wepreviously showed that Hsp27-S3D, a mutant mimicking phosphorylation, effectivelydecreased the percentage of cells containing aggresomes caused by an elongated huntingtinpolyglutamine tract (71Q-GFP) in BHK cells. We therefore created a transgenic mice withoverexpressing Hsp27-S3D. The founder mice had no abnormal phenotype, but unfortunately,did not pass the transgene to their offspring probably due to germ line toxicity.In this proposal, we want to directly express Hsp27-S3D by viral vectors to the brain totreat the HT R6/2 mice. We will use AAV1 vector to express the gene. AAV1 vector has beenshown to drive widespread expression in the brain. We will use stereotactic surgery to injectviral vector to the putamen. We will use vector expression GFP to verify the location of theinjection. After injection at age 4-6 weeks, R6/2 mice will be followed by Rotarod andgrasping. Brain histology will also offer the formation of inclusion body and cell death in thebrain. This study will effectively prove the possibility in establishing a new therapy to thepoly(Q) disease. This study will also help us to understand the mechanisms of the poly(Q)diseases.亨丁頓舞蹈症chaperoneHsp27AAVHuntington's diseasechaperoneHsp27AAV