Znf179是RING finger protein家族的一員。在胚胎發育的過程中，Znf179在腦部的表現會逐漸地增加，顯示Znf179可能影響神經系統的發育。實驗室過去的研究發現，在P19細胞分化為神經細胞的過程中，Znf179的確會隨著神經細胞的分化其表現量逐漸的增加，而在P19細胞進行神經細胞分化的過程中以shRNA去抑制Znf179的表現則會明顯地抑制神經細胞的分化。除了P19細胞外，抑制Znf179的表現同樣會影響初級培養的小腦神經顆粒細胞(cerebellar granule cells)的神經分化。進一步的研究發現Znf179可能透過影響p35及p27的基因表現而影響神經細胞的分化。為了更進一步釐清Znf179的生理作用及其對腦部發育的影響，在基因體醫學國家型科技計畫核心設施的協助下，我們建立了Znf179基因剔除小鼠。我們的研究結果顯示，在129/sv與C57BL/6J (B6)混合遺傳背景的小鼠中有超過70%的Znf179-/-小鼠會在離乳前死亡，而在129/sv純品系的小鼠中，超過75%的Znf179-/-小鼠會在胚胎時期死亡。我們發現大部分的Znf179-/-小鼠外表看起來蒼白，並且有血管的缺陷，顯示可能是由於血管生成的缺陷而導致Znf179-/-小鼠在胚胎時期死亡。 除此之外，我們也發現有些Znf179-/-小鼠有露腦畸形(exencephaly)的現象。當我們觀察存活下來的Znf179-/-小鼠時發現，Znf179-/-小鼠的體型較正常小鼠小，有生長遲緩的現象。除了體型外Znf179-/-小鼠的腦部也明顯地較小，切片染色的結果，初步顯示Znf179-/-小鼠腦部的結構除了大腦皮質較薄外與正常小鼠並沒有明顯的差異。綜合以上的結果顯示，Znf179基因對於胚胎發育具有重要的影響。

Znf179 is a member of the RING finger protein family. During embryogenesis, Znf179 is expressed in a restricted manner in the brain, suggesting a potential role in nervous system development. Previously, our laboratory found that the expression of Znf179 was upregulated during P19 cells neuronal differentiation. Inhibition of Znf179 expression by RNA interference significantly attenuated neuronal differentiation of P19 cells and the primary culture of cerebellar granule cells. Further studies revealed that the induction of Znf179 gene expression may be associated with p35 expression and p27 protein accumulation, and is critical for neuronal differentiation. To provide direct evidence on the physiological function of Znf179 on brain development, we generated Znf179 knockout mice to examine the function of Znf179 in vivo. Our data showed that more than 70% of Znf179-/- mice in the 129/sv x C57BL/6J (B6) mixed genetic background died before weaning. In contrast, most of the Znf179-/- mice in the pure 129/sv genetic background died in utero. Upon further investigation, we found that most of the Znf179-/- embryos looked pale and showed defect in blood vessels, suggesting that the embryonic lethality might be caused by impairing vasculogenesis. Moreover, some of the Znf179-/- embryos also exhibited exencephaly. The survived pups of Znf179-/- mice manifested growth retardation as indicated by smaller size. Although the organization of the brain did not appear to be affected in Znf179-/- mice, the brain size and the thickness of cerebral cortex from the Znf179-/- mice were reduced. Taken together, our results provide evidence for the important function of Znf179 in embryo development.

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