在斑馬魚早期胚胎發育的過程中，Wnt訊息傳遞路徑參與體軸形成的調控，在maternal時期會調控背-腹側體軸生成，在zygotic時期則是會調控前-後側體軸生成。在人類的癌症研究中發現Myc基因位於Wnt訊息傳遞路徑的下游，受Wnt訊息傳遞路徑所調控。Mych基因為Myc基因家族的一員，在先前的研究中發現斑馬魚mych基因在胚胎發育過程中會影響神經嵴的存活，但並未分析mych基因的5’未轉譯序列的作用，且未探討mych基因對體軸發育的影響，因此本研究想探討斑馬魚mych基因5’未轉譯序列的作用及mych基因對體軸發育的影響。在本研究中發現斑馬魚mych基因有兩種不同形式的mRNA，分別為mych-001及mych-002，此兩種形式的mRNA只在5’未轉譯序列有所不同，但從實驗結果卻發現mych-002 mRNA的轉譯效率要比mych-001 mRNA高上許多。從全胚胎原位雜交及reporter assay的結果則發現mych基因參與在Wnt訊息傳遞路徑中，並藉由影響ved、vent、vox基因的表現調控背-腹側體軸生成，當mych基因過度表現會造成胚胎腹側化，mych基因表現受抑制則會造成胚胎背側化。

In vertebrates, body axis formed during early embryogenesis. According to the earlier studies, Wnt signaling pathway controls dorsal-ventral body axis in blastrula and controls anterior-posterior body axis in gastrula. In human, Myc gene is at down stream of Wnt signaling pathway and the product of Myc gene is a transcription factor that involved in regulating many cell functions including cell proliferation or cell cycle progression. In previous study, Dawid’s lab has found that in zebrafish, the mych (myc homolog) gene play an important role in controlling early neuron precursor cell development that are related to anterior neural tissue formation. However, the detail mechanism of how mych regulates the body asymmetry is still not totally analyzed. In the present study, we found two mRNA transcript of mych, mych-001 and mych-002 in the zebrafish genome. Mych-001 and mych-002 different in their 5’UTR region sequence when mych-001 is maternally expressed and mych-002 is zygotically expressed. But they have the same expression region. Overexpress mych cause embryo posteriorization or ventrolization, but knockdown mych cause embryo dorsalization, which is similar to bmp knockdown morphant. To clarify wether mych involves in Wnt signaling pathway or bmp signaling pathway, we performed report assay. The report assay shows mych may involves in Wnt signaling pathway and knockdown mych down-regulated wnt target gene axin2 also confirmed this result. Mych overexpression make ved, vent and vox expression area enlarged and ved, vent, vox inhibited chd expression thus cause embryo ventrolized. Knocking down mych reduced ved, vent and vox expression area and chd expression area enlarged cause embryo drosalized.

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