Williams Karla C, McNeilly Rachael E, Coppolino Marc G
Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada.
Department of Molecular and Cellular Biology, University of Guelph, Guelph, ON N1G 2W1, Canada
Mol Biol Cell. 2014 Jul 1;25(13):2061-70. doi: 10.1091/mbc.E13-10-0582. Epub 2014 May 7.
Movement through the extracellular matrix (ECM) requires cells to degrade ECM components, primarily through the action of matrix metalloproteinases (MMPs). Membrane type 1-matrix metalloproteinase (MT1-MMP) has an essential role in matrix degradation and cell invasion and localizes to subcellular degradative structures termed invadopodia. Trafficking of MT1-MMP to invadopodia is required for the function of these structures, and here we examine the role of N-ethylmaleimide-sensitive factor-activating protein receptor (SNARE)-mediated membrane traffic in the transport of MT1-MMP to invadopodia. During invadopodium formation in MDA-MB-231 human breast cancer cells, increased association of SNAP23, Syntaxin4, and vesicle-associated membrane protein 7 (VAMP7) is detected by coimmunoprecipitation. Blocking the function of these SNAREs perturbs invadopodium-based ECM degradation and cell invasion. Increased level of SNAP23-Syntaxin4-VAMP7 interaction correlates with decreased Syntaxin4 phosphorylation. These results reveal an important role for SNARE-regulated trafficking of MT1-MMP to invadopodia during cellular invasion of ECM.
细胞在细胞外基质（ECM）中移动需要细胞主要通过基质金属蛋白酶（MMPs）的作用来降解ECM成分。膜型1-基质金属蛋白酶（MT1-MMP）在基质降解和细胞侵袭中起关键作用，并定位于称为侵袭伪足的亚细胞降解结构。MT1-MMP运输到侵袭伪足是这些结构发挥功能所必需的，在此我们研究N-乙基马来酰亚胺敏感因子激活蛋白受体（SNARE）介导的膜运输在MT1-MMP运输到侵袭伪足过程中的作用。在MDA-MB-231人乳腺癌细胞形成侵袭伪足的过程中，通过免疫共沉淀检测到SNAP23、Syntaxin4和囊泡相关膜蛋白7（VAMP7）的结合增加。阻断这些SNARE的功能会干扰基于侵袭伪足的ECM降解和细胞侵袭。SNAP23-Syntaxin4-VAMP7相互作用水平的增加与Syntaxin4磷酸化水平的降低相关。这些结果揭示了在细胞侵袭ECM过程中，SNARE调节MT1-MMP运输到侵袭伪足的重要作用。
