在胚胎發育的過程中，中胚層的分化由許多轉錄因子活化或抑制基因的表現來調控。Zfh1 (Zinc finger homeodomain 1) 為一個重要的轉錄因子，在發育過程會表現在整個中胚層和其分化形成的組織。過去研究已知道在 zfh1 突變時，由中胚層分化而成的組織如骨骼肌、平滑肌與心肌會產生缺陷，且脂肪體和生殖腺體細胞的前驅細胞會減少。實驗室先前以 ChIP-seq 找出 Zfh1 在果蠅基因組中結合的位置。為了探討這些在 ChIP-seq 找到的 Zfh1 結合區域是否為啟動子，並調控其附近基因的表現，實驗室先前挑選了 10 個 Zfh1 結合的區域，將其序列接上報導基因 GFP 後，轉殖到果蠅胚胎內。我收集了這 10 個帶有 Zfh1 結合區域序列之果蠅的胚胎，接著以免疫組織染色分析，發現其中有 4 個被 Zfh1 結合區域的序列，都能驅動報導基因表現在中胚層的特定細胞群內，另外 4 個被 Zfh1 結合區域的序列都能驅動報導基因表現外胚層的特定細胞群中；並且重現了這些被 Zfh1 結合區域附近的基因的內源性表現。因此從本篇研究可證明這 8 個被 Zfh1 結合區域的序列為增強子。

During embryogenesis, mesoderm differentiation requires transcription factors for activating or repressing gene expression. Zfh1 (Zinc finger homeodomain 1), a transcription factor, is expressed in the entire mesoderm during mesoderm specification. Previous studies showed that zfh1 mutants have defects in somatic, visceral, and cardiac muscles and also the reduced precursor cell numbers of fat body and somatic gonad. Our lab has used ChIP-seq to obtain the genome-wide Zfh1 binding regions. To determine whether these Zfh1-bound genomic regions are enhancers and regulate the nearby genes, I immunostained embryos from ten transgenic fly lines which carry individual Zfh1-bound regions with reporter gene GFP. I found that eight zfh1 target regions are expressed in specific cell populations of the mesoderm and ectoderm, and individually recapitulate the endogenous expression of their neighboring genes. These results suggest that the eight Zfh1-bound genomic regions are active enhancers that regulate the expression of their nearby genes.

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