BMP-1-like protease effects on growth factors & hormones

BMP-1 样蛋白酶对生长因子的影响

• 批准号: 6812089
• 负责人: DANIEL S GREENSPAN
• 金额: $ 26万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-01 至 2008-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6812089
• 关键词: bone morphogenetic proteins; chemical cleavage; endopeptidases; gene targeting; genetic manipulation; glycoproteins; growth factor; hormones; inhibitor /antagonist; laboratory mouse; myostatin; prolactin; protein protein interaction; protein sequence; protein structure function; proteolysis; somatomammotropin; somatotropin; transforming growth factors

DESCRIPTION (provided by applicant): The 4 mammalian BMP-l-like proteases (BLPs) play central roles in forming the ECM through biosynthetic processing of precursors, and enhance BMP signaling by cleaving the extracellular antagonist Chordin. Here we show BLPs to cleave prodomain sequences of the TGF-b-like factor gdf-8 (myostatin). Secreted gdf-8 is normally noncovalently bound to its prodomain in a latent complex. Cleavage of prodomain sequences by BLPs is shown to activate gdf-8. Golf-8 inhibits muscle growth, and mutation of the prodomain BLP cleavage site is shown to make the prodomain a powerful stimulator of muscle growth when administered to adult mice. Thus, cleavage at this site is biologically important. We propose showing which BLP may be responsible for activating gdf-8 in vivo. Gdf-11 (BMP-11) and gdf-8 form a subfamily of TGF-b-like molecules based on sequence homologies in their mature regions. We have preliminary evidence that the gdf-11 propeptide is cleaved by BLPs. We propose showing that mature secreted gdf-11 noncovalently binds its prodomain, that BLPs cleave the prodomain to release and activate mature gdf-11, and that this occurs in vivo. Gdf-11 is an inhibitor of neural tissue formation. Therefore, characterizing the mechanisms for in vivo activation of gdfs 8 and 11 has important implications for how such activation might be blocked, and thus how muscle and nerve regeneration may be enhanced in musculo- and neuro-degenerative diseases. We also propose determining which BI-Ps may cleave extracellular BMP antagonists Chordin-like 1 and 2, which show much overall homology with Chordin and which show indications of being regulated via proteolysis. In addition, we present evidence that BLPs may be involved in processing members of the prolactin, growth hormone/placental lactogen family of hormones to produce specific 16 kDa product. We propose determining which of these hormones are cleaved by which BLPs, at which sites, and whether such cleavages occur in vivo. Previous reports indicate that 16 kDa products of these hormones to biologically important. Thus, determining how these fragments are formed is of potential importance in regulating human endocrine functions. Conditional knockout mice for BLP genes will be created, for in vivo portions of the projects described above, and for future studies of the tissue-specific roles of BLPs in development and homeostasis. Finally, we present evidence for and propose experiments to further determine in vivo roles for the precursor forms and prodomains of BLPs in development and homeostasis.

描述(申请人提供)：4个哺乳动物骨形态发生蛋白-L样蛋白(BLP)通过前体的生物合成加工形成细胞外基质，并通过裂解细胞外拮抗剂Chordin来增强骨形态发生蛋白信号。在这里，我们展示了BLPS裂解转化生长因子样因子GDF-8(肌肉生长抑素)的前域序列。分泌的GDF-8通常以非共价方式与其潜伏复合体中的原结构域结合。BLPS切割前结构域序列可以激活GDF-8。高尔夫-8抑制肌肉生长，原结构域BLP裂解位点的突变被证明使原结构域成为成年小鼠肌肉生长的强大刺激因素。因此，这一部位的卵裂具有重要的生物学意义。我们建议显示哪些BLP可能负责在体内激活GDF-8。GDF-11(BMP-11)和GDF-8根据其成熟区域的序列同源性形成了一个类似于转化生长因子-b的分子亚家族。我们有初步证据表明GDF-11前肽被BLPS切割。我们建议证明成熟的分泌的GDF-11与其原结构域非共价结合，BLPS裂解原结构域释放并激活成熟的GDF-11，这在体内发生。GDF-11是一种神经组织形成的抑制剂。因此，表征Gdfs8和11在体内激活的机制对于如何阻止这种激活，从而在肌肉和神经退行性疾病中如何增强肌肉和神经的再生具有重要的意义。我们还建议确定哪些BI-Ps可以切割细胞外BMP拮抗剂Chordin样1和2，它们与Chordin总体上显示出很大的同源性，并且有迹象表明它们是通过蛋白分解来调节的。此外，我们提供的证据表明，BLPS可能参与了催乳素、生长激素/胎盘催乳素家族成员的加工，以产生特定的16 kDa产物。我们建议确定这些激素中的哪一种被哪一种BLP切割，在哪些位置，以及这种切割是否在体内发生。以往的报道表明，16 kDa的产物对这些激素具有重要的生物学意义。因此，确定这些片段是如何形成的，对于调节人类内分泌功能具有潜在的重要意义。BLP基因的条件性基因敲除小鼠将被创造出来，用于上述项目的体内部分，以及未来对BLP在发育和动态平衡中的组织特异性作用的研究。最后，我们为进一步确定BLPS的前体形式和前体结构域在发育和内稳态中的作用提供了证据并提出了实验建议。