Division of Dental Surgery, Nihon University School of Medicine, Tokyo 173-8610, Japan.
Biochem Biophys Res Commun. 2010 Mar 19;393(4):757-61. doi: 10.1016/j.bbrc.2010.02.076. Epub 2010 Feb 18.
Mouse Del1 is an extracellular matrix protein mainly expressed in the developing embryo. Del1 has three EGF motifs and two discoidin domains. The second EGF motif reportedly contains an RGD sequence that binds to integrin receptors. Here, we provide evidence that Del1 protein induces cell death in vitro. Chromatin condensation and DNA laddering were observed, suggestive of apoptosis. The results of analysis using the TUNEL method and annexin V staining were also consistent with apoptosis. The apoptosis-inducing activity of Del1 could be mapped to the third EGF motif, which fitted the consensus sequence CX(D/N)XXXX(F/Y)XCXC, wherein the aspartic acid residue (D) could be beta-hydroxylated. As little as twenty-five picomolar of recombinant E3 could induce apoptosis.
鼠 Del1 是一种细胞外基质蛋白，主要在发育中的胚胎中表达。Del1 具有三个 EGF 基序和两个盘状结构域。据报道，第二个 EGF 基序含有一个 RGD 序列，可与整合素受体结合。在这里，我们提供了 Del1 蛋白在体外诱导细胞死亡的证据。观察到染色质浓缩和 DNA 梯状，提示细胞凋亡。TUNEL 法和膜联蛋白 V 染色分析的结果也与细胞凋亡一致。Del1 的促凋亡活性可定位于第三个 EGF 基序，该基序符合 CX(D/N)XXXX(F/Y)XCXC 共识序列，其中天冬氨酸残基（D）可被β-羟化。仅二十五皮摩尔的重组 E3 即可诱导细胞凋亡。
