Whiteside E J, Kan M, Jackson M M, Thompson J G, McNaughton C, Herington A C, Harvey M B
Centre for Molecular Biotechnology, School of Life Sciences, Queensland University of Technology, Brisbane, Australia.
Anat Embryol (Berl). 2001 Dec;204(6):477-83. doi: 10.1007/s429-001-8004-7.
Several extracellular matrix (ECM)-degrading proteinases are hypothesised to play important roles during early mammalian development. In particular, urokinase-type plasminogen activator (uPA) and matrix metalloproteinase 9 (MMP-9) are expressed in peri-implantation mouse, sheep, and pig embryos and are implicated in the implantation process. These proteinases are not expressed in early (pre-blastocyst) mouse, sheep or pig embryos. The aim of this study was to establish the gene expression and proteolytic activity of uPA and MMP-9 in in vitro-produced (IVP) cow embryos. Using RT-PCR, mRNA transcripts for uPA and MMP-9 were detected during the first 7 days of development. To investigate the activity of these proteinases, conditioned media from various stages of development (days 2, 3, 4, 5 and 7) were assayed for uPA activity by chromogenic assay and MMP-9 activity by gelatin zymography. Both uPA and MMP-9 activities were detected in the media samples indicating the production and secretion of these proteinases. This pattern of proteinase expression is novel in comparison to the mouse where uPA and MMP-9 are only expressed from the blastocyst stage onwards. The results of this study suggest that these ECM proteinases have a role prior to implantation in the cow, in contrast to that exhibited by mouse, sheep and pig embryos.
几种细胞外基质（ECM）降解蛋白酶被认为在哺乳动物早期发育过程中发挥重要作用。特别是，尿激酶型纤溶酶原激活剂（uPA）和基质金属蛋白酶9（MMP-9）在着床前后的小鼠、绵羊和猪胚胎中表达，并与着床过程有关。这些蛋白酶在早期（囊胚前）小鼠、绵羊或猪胚胎中不表达。本研究的目的是确定体外生产（IVP）的牛胚胎中uPA和MMP-9的基因表达和蛋白水解活性。使用逆转录聚合酶链反应（RT-PCR），在发育的前7天检测到uPA和MMP-9的mRNA转录本。为了研究这些蛋白酶的活性，通过发色测定法检测不同发育阶段（第2、3、4、5和7天）的条件培养基中的uPA活性，并通过明胶酶谱法检测MMP-9活性。在培养基样品中检测到uPA和MMP-9的活性，表明这些蛋白酶的产生和分泌。与小鼠相比，这种蛋白酶表达模式是新颖的，在小鼠中uPA和MMP-9仅从囊胚阶段开始表达。本研究结果表明，与小鼠、绵羊和猪胚胎不同，这些ECM蛋白酶在牛着床前发挥作用。
