Lu H, Dhanabal M, Volk R, Waterman M J, Ramchandran R, Knebelmann B, Segal M, Sukhatme V P
Department of Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, 02215, USA.
Biochem Biophys Res Commun. 1999 May 19;258(3):668-73. doi: 10.1006/bbrc.1999.0612.
Angiostatin which contains the first four kringle domains of plasminogen has been documented to be a potent inhibitor of angiogenesis. More recently, another kringle structure within plasminogen but outside angiostatin, known as kringle 5 (K5), was found to inhibit endothelial cell proliferation and migration. Here, we report the cloning and expression of mouse kringle 5 (rK5) in a bacterial expression system. The protein was purified to homogeneity using a Ni-NTA column. rK5 inhibited both proliferation and migration of endothelial cells with ED50's of 10 nM and < 500 nM, respectively. In addition, we show for the first time that rK5 causes cell cycle arrest and apoptosis, shedding further insight into rK5's mechanism of action. Finally, we show that these actions are endothelial cell specific.
血管抑素包含纤溶酶原的前四个kringle结构域，已被证明是一种有效的血管生成抑制剂。最近，在纤溶酶原内但在血管抑素之外的另一种kringle结构，称为kringle 5（K5），被发现可抑制内皮细胞的增殖和迁移。在此，我们报告小鼠kringle 5（rK5）在细菌表达系统中的克隆和表达。使用镍-氮川三乙酸（Ni-NTA）柱将该蛋白纯化至同质。rK5分别以10 nM和<500 nM的半数有效剂量（ED50）抑制内皮细胞的增殖和迁移。此外，我们首次表明rK5导致细胞周期停滞和凋亡，进一步深入了解rK5的作用机制。最后，我们表明这些作用是内皮细胞特异性的。
