老鼠krüppel-like factor 4 (Klf4)是一個具有鋅手指的轉錄因子並且為大腸內杯狀細胞最終分化所必需。然而，在Klf4剃除小鼠或有條件刪除Klf4小鼠的研究顯示，Klf4於兩者的研究在胃上皮細胞增生呈現不同結果。我們利用斑馬魚為模式生物以了解Klf4在腸道細胞增生與分化所扮演的角色。
藉由反義核苷酸抑制基因表現，我們鑑定出與哺乳動物同源的klf4a之功能。經由胺基酸序列比較分析，斑馬魚Klf4a和人類及小鼠的Klf4的胺基酸序列具有高度相似性。於系統發生分析發現，斑馬魚Klf4a被歸類於和人類及小鼠同一演化分支上。斑馬魚、人類及小鼠的Klf4分別位於21號染色體、9號染色體及4號染色體。染色體保守性分析結果顯示，Klf4所座落的染色體於不同物種間呈現高度的保守性。在這個研究中，發現Klf4a在斑馬魚有許多功能，包含抑制腸道細胞增生、幫助腸道杯狀細胞分化及腸道吸收型細胞的最終分化。此外，klf4a的表現和脊椎動物一樣，皆是受到Notch訊號傳遞所抑制。
另一方面，為了瞭解斑馬魚agr2的功能，我們轉殖出由6Kb的agr2啟動子所調控綠螢光蛋白表現之斑馬魚品系。利用流式細胞儀收集發育到24、48、72及96小時的綠螢光細胞。由這些agr2表現與否的細胞中，萃取出RNA並藉由次世代定序分析呈現基因表現量之差異，可得1434個基因在agr2表現細胞中高量表現，另外有1990個基因在agr2表現細胞中反而表現下降。除此之外，更利用不同生物資訊分析法包含基因本體(GO)及綜合網路分析(IPA)去分析這些在agr2表現細胞的基因。結果顯示Agr2不只為蛋白質雙硫鍵異構酶，並且為免疫系統中的一個重要分子。利用IPA分析法發現次世代定序所得基因中，有一部分基因和黏液相關，另有一部分基因則和黏液完全不相關。我們選殖出部分基因並經由全覆式雜交染色法，發現大部分選殖的基因皆於中樞神經系統、胸鰭及咽弧中表現。

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