Thrombospondin type I domain containing 7A (THSD7A)，一個新穎蛋白質，被發現可大量表現於神經系統且影響內皮細胞的遷移及血管形成。在這篇研究中，我們研究其轉譯後修飾作用以及引發血管新生的下游機制，以探討 THSD7A 在血管新生過程中如何調控血管生長。我們以 Western blot分析 Full-length THSD7A-transfected human embryonic kidney 293T cells (HEK293T) 發現 THSD7A 是一個 membrane associated N-glycoprotein；且在 cultured medium 中，發現一個 THSD7A 的 soluble form。我們收集了 soluble THSD7A 並進行 angiogenic assays 發現 soluble THSD7A 能促進 human umbilical vein endothelial cell (HUVEC) 的移動、管柱生成和新芽生成。而在斑馬魚動物實驗中，發現 soluble THSD7A 能夠有效的增加 subintestinal vessel (SIV) 新生血管的分支數目，形成不正常的血管網路。有趣的是，我們同時也觀察到有 soluble THSD7A存在時，HUVEC 會有較多的 filopodia。vinculin 以及phosphorylated focal adhesion kinase (FAK) 在 HUVEC 中的分佈同樣也受到 soluble THSD7A 的影響，表示 soluble THSD7A 與 focal adhesion assembly 有關。HUVEC 中 FAK 的磷酸化程度同樣也被 soluble THSD7A 調控，暗示soluble THSD7A 可能影響細胞骨架的重組。綜合以上實驗結果，我們驗證了THSD7A，一個 membrane associated N-glycoprotein，會釋放 soluble form 至細胞外。Soluble THSD7A 能在血管新生的過程中，經由 FAK-dependent mechanism 促進內皮細胞移動，而可能扮演一個新穎的神經血管作用因子。

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