Chen Li, Nakai Masaaki, Belton Robert J, Nowak Romana A
Department of Animal Sciences, University of Illinois, Urbana, Illinois 61801, USA.
Reproduction. 2007 Feb;133(2):405-14. doi: 10.1530/rep.1.01020.
Mouse embryo implantation is a highly invasive and controlled process that involves remodeling and degradation of the extracellular matrix of the uterus. Matrix metalloproteinases (MMPs) are the main proteinases facilitating this process. Extracellular matrix metalloproteinase inducer (EMMPRIN) can stimulate the production of MMPs and is required for successful implantation in the mouse. The aims of the present study were to examine the expression profiles of mRNA and proteins for EMMPRIN and MMPs in the developing mouse embryo in vitro, and to study whether EMMPRIN protein induces the production of MMPs by mouse blastocysts. EMMPRIN mRNA, detected by RT-PCR, was present at all stages of embryo development from the one-cell to the blastocyst outgrowth. EMMPRIN protein, observed by confocal microscopy, was present on the cell surface at the same stages of development as was the mRNA. Of seven MMPs studied, murine collagenase-like A (Mcol-A), murine collagenase-like B (Mcol-B) and gelatinase A (MMP-2) mRNAs were detected only in blastocyst outgrowths by RT-PCR. Gelatinase B (MMP-9) mRNA was detected both in expanded blastocysts and blastocyst outgrowths. MMP-2 and -9 proteins were detected in the cytoplasm of outgrowing trophoblast cells. Collagenase-2 (MMP-8), collagenase-3 (MMP-13), or stromelysin-1 (MMP-3) mRNAs were not present at any stage of pre- or peri-implantation mouse embryo development. Quantitative RT-PCR analyses showed that recombinant EMMPRIN protein did not stimulate MMP-2 or -9 expression by mouse blastocyst outgrowths. These data suggest that EMMPRIN may regulate physiological functions other than MMP production by mouse embryos during implantation.
小鼠胚胎着床是一个高度侵入性且受调控的过程，涉及子宫细胞外基质的重塑和降解。基质金属蛋白酶（MMPs）是促进这一过程的主要蛋白酶。细胞外基质金属蛋白酶诱导剂（EMMPRIN）可刺激MMPs的产生，是小鼠成功着床所必需的。本研究的目的是检测体外发育的小鼠胚胎中EMMPRIN和MMPs的mRNA和蛋白质表达谱，并研究EMMPRIN蛋白是否诱导小鼠囊胚产生MMPs。通过RT-PCR检测到，从单细胞到囊胚外植体的胚胎发育各阶段均存在EMMPRIN mRNA。通过共聚焦显微镜观察到，EMMPRIN蛋白在与mRNA相同的发育阶段存在于细胞表面。在所研究的七种MMPs中，通过RT-PCR仅在囊胚外植体中检测到小鼠胶原酶样A（Mcol-A）、小鼠胶原酶样B（Mcol-B）和明胶酶A（MMP-2）的mRNA。在扩张囊胚和囊胚外植体中均检测到明胶酶B（MMP-9）的mRNA。在滋养层细胞外植体的细胞质中检测到MMP-2和-9蛋白。在植入前或植入期小鼠胚胎发育的任何阶段均未检测到胶原酶-2（MMP-8）、胶原酶-3（MMP-13）或基质溶解素-1（MMP-3）的mRNA。定量RT-PCR分析表明，重组EMMPRIN蛋白不会刺激小鼠囊胚外植体产生MMP-2或-9。这些数据表明，EMMPRIN可能在着床期间调节小鼠胚胎除MMP产生之外的其他生理功能。
