生物的基因體中存在著許多轉錄控制因子 (transcriptional controlling elements) ，生物體透過轉錄作用表達基因之後進行轉譯成蛋白質，加強子 (Enhancer) 為其中一種轉錄控制因子，具有幾個特點: 1.可以位於被轉錄基因的上游或下游，2.可以與轉錄活化子 ( transcription activator) 或轉錄抑制子 (transcription repressor) 結合，進而活化或抑制基因的表現，3.隨著在特定組織中表現的轉錄因子 (transcription factor) 而具有組織特異性，在特定細胞中調控特定基因的表現，4.一個加強子或可調控多個基因。
加強子在果蠅發育的過程中扮演著調控基因在不同發育時期以及特定細胞表現的重要角色，許多加強子在發育的過程中會驅動所控制的基因，使基因表現在某些特定的細胞中，為了了解加強子如何調控基因表現，我利用自維也納果蠅資源中心(Vienna Drosophila Resource Center , VDRC) 取得的10個VT lines果蠅株，以免疫染色去觀察這些果蠅株中所包含的DNA片段在果蠅發育過程中是否能作為加強子，驅動其下游的報導基因GFP表現在特定時期以及特定的細胞，並與柏克萊果蠅基因體計畫BDGP ( Berkeley Drosophila Genome Project ) 的結果比較，是否這些VT lines果蠅株基因體包含的DNA片段調控基因在果蠅胚胎的表現型態 (gene expression) 與BDGP基因的表現型態(gene expression)相同，以此確認這些VT lines果蠅基因體中的DNA片段是否為控制該目標基因的加強子。在所選的7個基因共10個VT lines中有4個基因，分別為Bx、CG10479、Srp、nemy的VT lines果蠅株中所選殖的DNA片段的確是調控其基因表現的加強子。

There are many transcriptional controlling elements in an organism’s genome. The organism expresses the gene through transcription and then translation. The enhancer is one of the transcriptional regulatory elements. It has several characteristics: 1. It can be located upstream or downstream of the transcribed gene. 2. It can bind with many different transcription factors, including transcription activators and transcription repressors, thereby activating and repressing the expression of different genes.3. It is tissue-specific, regulating the expression of specific genes in specific tissues. 4. One enhancer can possibly regulate many expressions of many genes.
My thesis is to observe the expression of certain genomic regions and measure if they act as enhancers. I picked 10 VT lines, which are from Vienna Drosophila Resource Center (VDRC). Their genomic regions around 7 target genes, including Beadex (Bx), CG10479, Serpent (Srp), Abdominal B (AbdB), pointed (pnt), CG8745, no extended memory (nemy). I used immunostaining to see if they drive the expression of the reporter gene GFP. I compared these expression patterns of VT lines with the results of BDGP (Berkeley Drosophila Genome Project), which represents the endogenous expression of the target gene. I found that the genomic regions around four genes, Bx, CG10479, Srp and nemy, drives similar expression patterns as the endogenous expression of genes. I therefore confirmed the genomic regions around genes, Bx, CG10479, Srp and nemy are functional enhancers.

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