The mitochondrial rhomboid protease PARL regulates mitophagy by balancing intramembrane proteolysis of PINK1 and PGAM5. It has been implicated in the pathogenesis of Parkinson's disease, but its investigation as a possible therapeutic target is challenging in this context because genetic deficiency of PARL may result in compensatory mechanisms. To address this problem, we undertook a hitherto unavailable chemical biology strategy. We developed potent PARL-targeting ketoamide inhibitors and investigated the effects of acute PARL suppression on the processing status of PINK1 intermediates and on Parkin activation. This approach revealed that PARL inhibition leads to a robust activation of the PINK1/Parkin pathway without major secondary effects on mitochondrial properties, which demonstrates that the pharmacological blockage of PARL to boost PINK1/Parkin-dependent mitophagy is a feasible approach to examine novel therapeutic strategies for Parkinson's disease. More generally, this study showcases the power of ketoamide inhibitors for cell biological studies of rhomboid proteases.

• MeSH
• endopeptidasy MeSH
• lidé MeSH
• metaloproteasy genetika   metabolismus   MeSH
• mitochondriální proteiny metabolismus   MeSH
• mitofagie MeSH
• Parkinsonova nemoc * farmakoterapie   MeSH
• proteasy * MeSH
• proteinkinasy metabolismus   MeSH
• ubikvitinligasy metabolismus   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The rhomboid superfamily of transmembrane (TM) proteins includes intramembrane serine proteases and several classes of pseudoprotease. Rhomboid-like proteins occur widely across evolution and comprise biologically important regulators of fate of membrane proteins, influencing their proteolysis, trafficking, or degradation. In this review, we discuss how structural and mechanistic insights into the action of rhomboid proteases can inform on the mechanism of the pseudoproteases, and discuss the impact of structural understanding on the development of inhibitors and other chemical biology tools for these proteins. Development of modulators would be particularly relevant for the iRhoms, which are key regulators of ADAM17 and, hence, tumor necrosis factor (TNF) and epidermal growth factor receptor (EGFR) signaling, two medically important pathways.

• MeSH
• lidé MeSH
• membránové proteiny genetika   metabolismus   MeSH
• protein ADAM17 genetika   metabolismus   MeSH
• proteolýza * MeSH
• signální transdukce fyziologie   MeSH
• TNF-alfa genetika   metabolismus   MeSH
• transport proteinů fyziologie   MeSH
• vztahy mezi strukturou a aktivitou MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

Rhomboid-family intramembrane proteases regulate important biological processes and have been associated with malaria, cancer, and Parkinson's disease. However, due to the lack of potent, selective, and pharmacologically compliant inhibitors, the wide therapeutic potential of rhomboids is currently untapped. Here, we bridge this gap by discovering that peptidyl α-ketoamides substituted at the ketoamide nitrogen by hydrophobic groups are potent rhomboid inhibitors active in the nanomolar range, surpassing the currently used rhomboid inhibitors by up to three orders of magnitude. Such peptidyl ketoamides show selectivity for rhomboids, leaving most human serine hydrolases unaffected. Crystal structures show that these compounds bind the active site of rhomboid covalently and in a substrate-like manner, and kinetic analysis reveals their reversible, slow-binding, non-competitive mechanism. Since ketoamides are clinically used pharmacophores, our findings uncover a straightforward modular way for the design of specific inhibitors of rhomboid proteases, which can be widely applicable in cell biology and drug discovery.

• MeSH
• gramnegativní bakterie enzymologie   MeSH
• grampozitivní bakterie enzymologie   MeSH
• inhibitory serinových proteinas chemická syntéza   chemie   farmakologie   MeSH
• molekulární konformace MeSH
• molekulární modely MeSH
• proteasy metabolismus   MeSH
• racionální návrh léčiv * MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH