Mechanisms and Function of Intramembrane Proteolysis by the gramme-Secretase homologous Signal Peptide Peptidase-like Proteases (SPPL)

革兰氏分泌酶同源信号肽肽酶样蛋白酶 (SPPL) 膜内蛋白水解的机制和功能

• 批准号: 25923830
• 负责人: Professor Dr. Christian Haass
• 金额: --
• 依托单位: Munich Cluster for Systems Neurology (SyNergy)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2006
• 资助国家: 德国
• 起止时间: 2005-12-31 至 2013-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/25923830?language=en
• 关键词: Mechanisms; Function; Intramembrane; Proteolysis; gramme

Intramembrane proteolysis was thought to be biochemically impossible, because each protease requires water for its catalytic activity. However, upon investigation of the proteolytic generation of the Alzheimer¿s disease associated Amyloid ß-peptide it became clear that ¿-secretase can indeed cut in the middle of the membrane in a hydrophobic environment under physiological conditions. Whereas ¿-secretase exclusively cuts type 1 trans-membrane domain proteins, signal peptide peptidase (SPP) only accepts type 2 oriented proteins as substrates. Data bank analysis lead to the identification of a family of SPP-like proteins (SPPL2a,b,c and SPPL3), whose function is until now completely unknown. Very recently we were able to demonstrate that SPPLs, like ¿-secretase, belong to the GxGD type-aspartyl proteases, which we originally defined as a new class of intramembrane cleaving proteases. We are now interested to understand the function of the SPPLs and the mechanisms by which they are able to cleave within the membrane. We will identify their substrates and will subsequently investigate substrate processing in vivo and in vitro to determine the cleavage sites, cleavage site requirements and a putative mechanistic analogy to ¿-secretase. Substrates will be verified by rescuing knock down phenotypes in an animal model (zebrafish) upon expression of the recombinant cleavage products. Our findings will contribute to the understanding of the novel scheme of intramembrane proteolysis by GxGD proteases, which appears to be of great importance in pivotal physiological and pathological processes, such as Alzheimer¿s disease, Cholesterol metabolism, Notch-signaling, removal of signal peptides, immune surveillance, and processing of the Hepatitis C viral core protein.

膜内蛋白水解在生物化学上被认为是不可能的，因为每一种蛋白酶都需要水来发挥催化活性。然而，通过对阿尔茨海默病相关淀粉样蛋白ß-肽的蛋白水解生成的研究表明，在生理条件下疏水环境下，β -分泌酶确实可以在膜的中间切割。分泌酶专门切割1型跨膜结构域蛋白，而信号肽肽酶（SPP）只接受2型定向蛋白作为底物。数据库分析鉴定了spp样蛋白家族（SPPL2a,b，c和SPPL3），其功能迄今为止完全未知。最近，我们能够证明sppl，像分泌酶一样，属于GxGD型天冬氨酸蛋白酶，我们最初将其定义为一类新的膜内切割蛋白酶。我们现在有兴趣了解sppl的功能和它们能够在膜内切割的机制。我们将鉴定它们的底物，随后将研究底物在体内和体外的加工过程，以确定裂解位点、裂解位点要求以及与分泌酶的推测机制类比。底物将通过在动物模型（斑马鱼）中表达重组切割产物来验证敲低表型。我们的研究结果将有助于理解GxGD蛋白酶膜内蛋白水解的新机制，该机制在关键的生理和病理过程中具有重要意义，如阿尔茨海默病、胆固醇代谢、notch信号、信号肽的去除、免疫监视和丙型肝炎病毒核心蛋白的加工。

项目成果

Foamy Virus Envelope Protein Is a Substrate for Signal Peptide Peptidase-like 3 (SPPL3)*

• DOI: 10.1074/jbc.m112.371369
• 发表时间: 2012-11
• 期刊: The Journal of Biological Chemistry
• 作者: M. Voss;Akio Fukumori;Peer-Hendrik Kuhn;U. Künzel;Bärbel Klier;Gudula Grammer;Martina Haug-Kröper;E. Kremmer;S. Lichtenthaler;H. Steiner;B. Schröder;C. Haass;Regina Fluhrer

The transferrin receptor‐1 membrane stub undergoes intramembrane proteolysis by signal peptide peptidase‐like 2b

转铁蛋白受体 1 膜短端通过信号肽类肽酶 2b 进行膜内蛋白水解

• DOI: 10.1111/febs.12176
• 发表时间: 2013
• 期刊: The FEBS Journal
• 作者: C.Zahn;M. Kaup;R. Fluhrer;H. Fuchs
• 通讯作者: H. Fuchs

The Intramembrane Protease SPPL2A Is Critical for Tooth Enamel Formation

• DOI: 10.1002/jbmr.1895
• 发表时间: 2013-07-01
• 期刊: JOURNAL OF BONE AND MINERAL RESEARCH
• 影响因子: 6.2
• 作者: Bronckers, Antonius L. J. J.;Gueneli, Nur;Schroeder, Bernd
• 通讯作者: Schroeder, Bernd