神經網路的形成是腦雌雄性別分化的關鍵，神經的發育決定神經網路的型塑。本研究室以莫三比克口孵吳郭魚 (Oreochromis mossambicus)為探討腦性別分化 (brain sexual differentiation)的模式動物。本研究室已建立吳郭魚腦發育初期的表現基因資料庫 (Expressed Sequence Tags, ESTs)。本論文針對其中一條神經發育相關的基因，DLX6 (Distal-less homeobox 6)完成基因定序，並以原核生物表現系統進行DLX6的蛋白質表現，以E. coli量產，經6X-His tag column純化後取得DLX6，進一步探討DLX6形成dimer的可能性。另一方面，以老鼠神經母瘤細胞(Neuro-2a， N2a)為實驗模式細胞，應用轉染技術 (Transfection)，轉殖綠色螢光蛋白 (green fluorescent protein，GFP)基因，觀察DLX6蛋白質在N2a細胞中分佈的位置。

The unique gene, Distal-less homeobox (DLX6) was identified in the expressed sequence taq (EST) derived from the developing tilapia brain in our lab. The cDNA full length of DLX6 was cloned. DLX6 play a role in the differentiation of nerve cell. In this study, bioinformatics were searched for EE724153.1 (DLX6), which is a gene with 2138 bp of cDNA sequence, open reading frame(ORF) is 741bp, and deduced as 246 amino acids. The protein of DLX6 was expressed in the prokaryotic system, BL21(E.coli), and purified with Ni-NTA affinity chromatography. In the present studies, DLX6, cloned from tilapia, Oreochromis mossambicus. The possibility of DLX6 can form dimer. The ORF of DLX6 was cloned, and the pEGFP-DLX6 plasmid was constructed. The distribution of DLX6 in the pEGFP-DLX6 transfected Neuro-2a cell was identified by fluorescence .

致謝．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．i
中文摘要．．．．．．．．．．．．．．．．．．．．．．．．．．．．．ii
英文摘要．．．．．．．．．．．．．．．．．．．．．．．．．．．．．iii
前言．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．1
材料與方法．．．．．．．．．．．．．．．．．．．．．．．．．．．．4
結果．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．25
討論．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．27
參考文獻．．．．．．．．．．．．．．．．．．．．．．．．．．．．．30
圖次．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．．33

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