Bioluminescence imaging of MMP-2 and its related proteins secretion

基质金属蛋白酶-2是降解基底膜胶原的酶之一，在癌细胞侵袭中起重要作用。基质金属蛋白酶-2以非活性前体形式分泌，非活性前体与细胞表面结合，产生活性基质金属蛋白酶-2。我们已经建立了一种视频速率生物发光成像的方法来可视化单个活细胞的胞吐蛋白分泌。这种生物发光方法在估计细胞整个表面的蛋白质分泌量随时间的变化和/或显示蛋白质分泌的可视化方面具有优势。结果，我们证明了在细胞前沿的特定部位反复分泌基质金属蛋白酶-2。MMP2-Glase的生物发光视频图像分析显示，在细胞的前缘和底侧的特定位置重复分泌MMP2，提示MMP2的分泌部位与MMP2的结合部位不同。

MMP-2 is one of the enzymes in degradation of basement membrane collagen and has a major role in cancer cell invasion. MMP-2 is secreted as the inactive pro-form, and the inactive pro-form of MMP-2 binds on the cell surface, and then active MMP-2 is produced. We have established a method of video-rate bioluminescence imaging to visualize exocytotic protein secretion from a single living cell. This bioluminescence method has advantages for estimation of time-dependent changes of the amount of secreted protein and or visualization of protein secretion over the whole surface of a cell. As a result, we demonstrated that the repeated secretion of MMP-2 from specific sites at the leading edge of the cell. The analyses of bioluminescence video images of MMP2-GLase showed repeated secretion of MMP-2 from specific sites at the leading edge and bottom side of the cell, suggesting that the sites of MMP-2 secretion differ from the MMP-2 binding sites.