果蠅中胚層發育是一個逐漸縮小細胞可能發育命運範圍的過程。整個中胚層先由主導基因的表現決定，之後被分成不同區塊，每個區塊再發育成不同組織。D-six4 和 eya 基因在果蠅胚胎發育的早期於整個中胚層表現，之後侷限於頭部及腹部中胚層，影響頭部中胚層如血球細胞及腹部中胚層組織如脂肪體、生殖腺體細胞的特化與發育。RNAi 是近年來發展出來的一種藉由抑制基因表現研究基因功能的方法。利用在目標細胞內表現與內源基因同源的雙股 RNA (dsRNA) 序列，使內源的 mRNA 表達靜默，以達到抑制基因表現的目的。我建立了會在腹部中胚層表現的轉殖果蠅株 pPTGal4-six4， 並利用 GAL4-UAS 系統，使其與 RNAi 果蠅株雜交來篩選參與果蠅腹部中胚層發育過程的基因。我發現減低 CG10591、CG8981、CG3758 和 CG11068 基因在中胚層表現後會抑制 eya 基因在中胚層的表現。

Drosophila mesoderm development proceeds in a step-wise fashion. The whole mesoderm is first specified by the expression of a master gene and then subdivided into primordia of different tissues. D-six4 and Eya, a Six family transcription factor and its co-activator, respectively, are expressed in the whole mesoderm and then restricted to the ventral mesoderm. These two genes work together to affect the formation of the ventral mesodermal derivatives, such as fat body and somatic gonad. RNA interference (RNAi) has been shown to be a powerful method to study the function of genes in vivo by silencing endogenous mRNA with double-stranded (ds) RNA. The specification of dorsal mesodermal cell fate has been studied thoroughly while very little is known about the cell fate determination of the ventral mesoderm. In order to identify novel genes involved in Drosophila mesoderm development, I established pPTGal4-six4 transgenic fly lines, which drive specific gene expression in the mesoderm. I screened 46 genes through tissue-specific RNAi experiments and found that CG10591, CG8981, CG3758 and CG11068 may be involved in Drosophila mesoderm development.

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