AAV-BCAS2 在條件式剔除小鼠及阿茲海默症疾病模式小鼠中的治療效果

The therapeutic effect of AAV-BCAS2 in BCAS2 cKO and Alzheimer's disease model mice

呂晧瑜(Hao-Yu Lu)

指導教授 ： 陳小梨

國立臺灣大學/醫學院/微生物學研究所/碩士(2021年)

https://doi.org/10.6342/NTU202102685

摘要

BCAS2，也稱為pre-mRNA 剪接因子 (SPF27)，是一種大小為 26 kDa 的核蛋白，也是 hprp19 複合物的核心成分。 BCAS2參與pre-mRNA剪接，對細胞生長調控有很大影響。本實驗室先前的研究發現，BCAS2會參與DNA損傷修復和果蠅翅膀的發育，並且可以調節β-catenin pre-mRNA的剪接，本實驗室發現， CaMKIIα 驅動的 BCAS2 cKO 小鼠中的 β-catenin 表現量會降低。 有關β-catenin在神經元樹突生長中的調控已有大量文獻記載。在 BCAS2 cKO 小鼠中，我們觀察到 Ki67+ 細胞數量減少。Ki67 是一種常用的增殖標誌蛋白，這表明缺乏 BCAS2 可能會影響小鼠成年海馬迴神經新生。依據我們實驗室尚未發表的數據結果，透過 AAV-BCAS2 腦內注射增加 β-catenin的表現將改善 BCAS2 cKO 小鼠神經的樹突生長和學習行為測試的表現。因此，為了探究AAV target的細胞類型，我們在 WT 小鼠中進行了 AAV-DJ8 GFP 和 AAV-9 GFP 的顱內注射。結果表明，AAV 不僅可以target神經幹細胞和未成熟神經元，還可以target非神經元細胞，如星形膠質細胞和中間神經元。這些結果表示 AAV-BCAS2 可以透過自autonomous和non-autonomous effect調節神經發生。此外，我們想研究 AAV-BCAS2 是否會對 BCAS2 cKO 小鼠和阿茲海默疾病模式小鼠(APP)產生治療作用。結果表明，AAV-BCAS2 可以成功增加 cKO/BCAS2 小鼠中 Ki67+ 細胞的數量。在 APP 小鼠中，與 APP/GFP 對照小鼠相比，AAV-BCAS2 顱內注射還增加了 Ki67+ 和 DCX+ 細胞的數量。此外，與 APP/GFP 對照組相比，AAV-BCAS2 增加了 APP/BCAS2 小鼠中 β-catenin 蛋白的表現。

關鍵字

神經新生 ； BCAS2 ； β-catenin ； BCAS2條件式基因剔除小鼠(CAMKIIα-Cre；BCAS2flox/flox) ； 阿茲海默症 ； APP J20阿茲海默症疾病模式小鼠

並列摘要

Breast carcinoma amplified sequence 2 (BCAS2), also known as pre-mRNA-splicing factor (SPF27), is a 26 kDa nuclear protein and a core component of hprp19 complex. BCAS2 participates in pre-mRNA splicing and has a great impact on cell growth regulation. Previous researches in our lab have suggested that BCAS2 is involved in DNA damage repair and drosophila wings development, and it can regulate β-catenin pre-mRNA splicing. β-catenin protein level decreases in CaMKII driven BCAS2 cKO mice. β-catenin has been well documented about its regulation in neuron dendrite growth. In BCAS2 cKO mice, we observed a decreased number of Ki67+ cell, a commonly used proliferative marker, suggested that lack of BCAS2 could deficit adult hippocampal neurogenesis in murine. The unpublished data in our lab suggested that increasing β-catenin expression via AAV-BCAS2 brain injection would improve dendrite growth and performance of learning behavior test in BCAS2 cKO mice. Therefore, in order to examine AAV targeted cells types, we conducted an intracranial injection of AAV-DJ8 GFP andAAV-9 GFP in WT mice. The results indicated that AAV could target not only neural stem cells and immature neurons but also non neuronal cells, such as astrocytes and interneurons. These results suggested that AAV-BCAS2 could regulate neurogenesis through autonomous effect and non-autonomous effect. Furthermore, we want to investigate that weather AAV-BCAS2 will cause a therapeutic effect in BCAS2 cKO mice and Alzheimer’s disease model (APP) mice. the results demonstrated that AAV-BCAS2 could successfully increase the number of Ki67+ cells in cKO/BCAS2 mice. In APP mice, AAV-BCAS2 intracranial injection also increase the number of Ki67+ and DCX+ cells compared to APP/GFP control mice. Moreover, AAV-BCAS2 increase the β-catenin protein expression in APP/BCAS2 mice compared to APP/GFP control group.

並列關鍵字

adult neurogenesis ； BCAS2 ； β-catenin ； BCAS2 cKO mice (CAMKIIα-Cre；BCAS2flox/flox) ； Alzheimer's disease ； APP J20 mice

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