Coordinate expression and functional profiling identify an extracellular proteolytic signaling pathway
Coordinate expression and functional profiling identify an extracellular proteolytic signaling pathway
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DOI：
10.1073/pnas.0606514104
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发表时间：
2007-04-03
影响因子：
11.1
通讯作者：
Craik, Charles S.
中科院分区：
文献类型：
--
作者：
Bhatt, Ami S.;Welm, Alana;Craik, Charles S.
结合转录数据、特异性分析和酶的生物学特性的多学科方法可用于预测新的底物。通过将蛋白酶底物分析与来自近2000个人类正常和癌组织样本的微阵列基因共表达数据相结合，确定了蛋白酶激活信号通路的三个基本组成部分。我们发现MT-SP1通过调节原转移性生长因子MSP-1的局部激活来介导细胞外信号传导。我们证实了MT-SP1在腹膜巨噬细胞中的表达，生化方法证实了MT-SP1在体外和细胞环境中切割和激活前msp -1的能力。MT-SP1诱导MSP-1抑制骨髓巨噬细胞一氧化氮生成的能力。加入HAI-1或mt - sp1特异性抗体抑制剂可阻断MSP-1在腹腔巨噬细胞表面的蛋白水解激活。综上所述，我们的工作表明，MT-SP1足以激活MSP-1，并且MT-SP1、MSP-1和先前显示的MSP-1酪氨酸激酶受体RON是腹膜巨噬细胞激活所必需的。本研究表明，生长因子、生长因子激活因子蛋白酶和生长因子受体是一种由蛋白酶激活的信号通路。单独来看，MT-SP1和RON的过表达与癌症的进展和转移有关。这些基因的转录共表达表明，这种信号通路可能与几种人类癌症有关。
A multidisciplinary method combining transcriptional data, specificity profiling, and biological characterization of an enzyme may be used to predict novel substrates. By integrating protease substrate profiling with microarray gene coexpression data from nearly 2,000 human normal and cancerous tissue samples, three fundamental components of a protease-activated signaling pathway were identified. We find that MT-SP1 mediates extracellular signaling by regulating the local activation of the prometastatic growth factor MSP-1. We demonstrate MT-SP1 expression in peritoneal macrophages, and biochemical methods confirm the ability of MT-SP1 to cleave and activate pro-MSP-1 in vitro and in a cellular context. MT-SP1 induced the ability of MSP-1 to inhibit nitric oxide production in bone marrow macrophages. Addition of HAI-1 or an MT-SP1-specific antibody inhibitor blocked the proteolytic activation of MSP-1 at the cell surface of peritoneal macrophages. Taken together, our work indicates that MT-SP1 is sufficient for MSP-1 activation and that MT-SP1, MSP-1, and the previously shown MSP-1 tyrosine kinase receptor RON are required for peritoneal macrophage activation. This work shows that this triad of growth factor, growth factor activator protease, and growth factor receptor is a protease-activated signaling pathway. Individually, MT-SP1 and RON overexpression have been implicated in cancer progression and metastasis. Transcriptional coexpression of these genes suggests that this signaling pathway may be involved in several human cancers.