Youn Mi-Ran, Park Mee-Hee, Choi Chang-Ki, Ahn Byung-Cheol, Kim Hak Yong, Kang Sang Sun, Hong Yong-Kil, Joe Young Ae, Kim Jong-Soo, You Weon-Kyoo, Lee Hyo-Sil, Chung Soo-Il, Chang Soo-Ik
Department of Biochemistry, Chungbuk National University, Cheongju 361-763, Republic of Korea.
Biochem Biophys Res Commun. 2006 May 12;343(3):917-23. doi: 10.1016/j.bbrc.2006.03.043. Epub 2006 Mar 20.
Angiogenin is one of the most potent angiogenesis-inducing proteins. Angiostatin is one of the most potent angiogenesis inhibitors, and it contains the first four kringle domains of plasminogen (K1-4). Recombinant human plasminogen kringle 1-3 (rK1-3) was expressed in Escherichia coli and purified to homogeneity. The binding of t-4-aminomethylcyclohexanecarboxylic acid with the purified kringle 1-3 was determined by changes in intrinsic fluorescence. rK1-3 exhibits comparable ligand-binding properties as native human plasminogen kringle 1-3. The purified rK1-3 inhibits neovascularization in the chick embryo chorioallantoic membrane (CAM) assay. Interaction of angiogenin with rK1-3 was examined by immunological binding assay and surface plasmon resonance kinetic analysis, and the equilibrium dissociation constants for the complex, Kd, are 0.89 and 0.18 microM, respectively. rK1-3 inhibits angiogenin-induced angiogenesis in the chick embryo CAM in a concentration-dependent manner. These results indicate that rK1-3 directly binds to angiogenin and thus rK1-3 inhibits the angiogenic activity of angiogenin.
