1
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Lorthiois E, Roache J, Barnes-Seeman D, Altmann E, Hassiepen U, Turner G, Duvadie R, Hornak V, Karki RG, Schiering N, Weihofen WA, Perruccio F, Calhoun A, Fazal T, Dedic D, Durand C, Dussauge S, Fettis K, Tritsch F, Dentel C, Druet A, Liu D, Kirman L, Lachal J, Namoto K, Bevan D, Mo R, Monnet G, Muller L, Zessis R, Huang X, Lindsley L, Currie T, Chiu YH, Fridrich C, Delgado P, Wang S, Hollis-Symynkywicz M, Berghausen J, Williams E, Liu H, Liang G, Kim H, Hoffmann P, Hein A, Ramage P, D’Arcy A, Harlfinger S, Renatus M, Ruedisser S, Feldman D, Elliott J, Sedrani R, Maibaum J, Adams CM. Structure-Based Design and Preclinical Characterization of Selective and Orally Bioavailable Factor XIa Inhibitors: Demonstrating the Power of an Integrated S1 Protease Family Approach. J Med Chem 2020; 63:8088-8113. [DOI: 10.1021/acs.jmedchem.0c00279] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Edwige Lorthiois
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - James Roache
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - David Barnes-Seeman
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Eva Altmann
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - Ulrich Hassiepen
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - Gordon Turner
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Rohit Duvadie
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Viktor Hornak
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Rajeshri G. Karki
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Nikolaus Schiering
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - Wilhelm A. Weihofen
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Francesca Perruccio
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - Amy Calhoun
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Tanzina Fazal
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Darija Dedic
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - Corinne Durand
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - Solene Dussauge
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - Kamal Fettis
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - Fabien Tritsch
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - Celine Dentel
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - Adelaide Druet
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - Donglei Liu
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Louise Kirman
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Julie Lachal
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - Kenji Namoto
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - Douglas Bevan
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Rose Mo
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Gabriela Monnet
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - Lionel Muller
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - Richard Zessis
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Xueming Huang
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Loren Lindsley
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Treeve Currie
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Yu-Hsin Chiu
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Cary Fridrich
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Peter Delgado
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Shuangxi Wang
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | | | - Joerg Berghausen
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - Eric Williams
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Hong Liu
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Guiqing Liang
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Hyungchul Kim
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Peter Hoffmann
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Andreas Hein
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - Paul Ramage
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - Allan D’Arcy
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - Stefanie Harlfinger
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - Martin Renatus
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - Simon Ruedisser
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - David Feldman
- Novartis Institutes for BioMedical Research, East Hanover, New Jersey 07396, United States
| | - Jason Elliott
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
| | - Richard Sedrani
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - Juergen Maibaum
- Novartis Institutes for BioMedical Research, Novartis Campus, CH-4056 Basel, Switzerland
| | - Christopher M. Adams
- Novartis Institutes for BioMedical Research, Cambridge, Massachusetts 02139, United States
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2
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Ross NT, Lohmann F, Carbonneau S, Fazal A, Weihofen WA, Gleim S, Salcius M, Sigoillot F, Henault M, Carl SH, Rodríguez-Molina JB, Miller HR, Brittain SM, Murphy J, Zambrowski M, Boynton G, Wang Y, Chen A, Molind GJ, Wilbertz JH, Artus-Revel CG, Jia M, Akinjiyan FA, Turner J, Knehr J, Carbone W, Schuierer S, Reece-Hoyes JS, Xie K, Saran C, Williams ET, Roma G, Spencer M, Jenkins J, George EL, Thomas JR, Michaud G, Schirle M, Tallarico J, Passmore LA, Chao JA, Beckwith REJ. Author Correction: CPSF3-dependent pre-mRNA processing as a druggable node in AML and Ewing's sarcoma. Nat Chem Biol 2020; 16:479. [PMID: 32139909 DOI: 10.1038/s41589-020-0508-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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Affiliation(s)
- Nathan T Ross
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA.,Vertex Pharmaceuticals, Boston, MA, USA
| | - Felix Lohmann
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Seth Carbonneau
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Aleem Fazal
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | | | - Scott Gleim
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Michael Salcius
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | | | - Martin Henault
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Sarah H Carl
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | | | - Howard R Miller
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | | | - Jason Murphy
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Mark Zambrowski
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | | | - Yuan Wang
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Aye Chen
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | | | - Johannes H Wilbertz
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | | | - Min Jia
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | | | - Jonathan Turner
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Judith Knehr
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Walter Carbone
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Sven Schuierer
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | | | - Kevin Xie
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Chitra Saran
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Eric T Williams
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Guglielmo Roma
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Matt Spencer
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Jeremy Jenkins
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | | | - Jason R Thomas
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Gregory Michaud
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Markus Schirle
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - John Tallarico
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Lori A Passmore
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Jeffrey A Chao
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
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3
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Ross NT, Lohmann F, Carbonneau S, Fazal A, Weihofen WA, Gleim S, Salcius M, Sigoillot F, Henault M, Carl SH, Rodríguez-Molina JB, Miller HR, Brittain SM, Murphy J, Zambrowski M, Boynton G, Wang Y, Chen A, Molind GJ, Wilbertz JH, Artus-Revel CG, Jia M, Akinjiyan FA, Turner J, Knehr J, Carbone W, Schuierer S, Reece-Hoyes JS, Xie K, Saran C, Williams ET, Roma G, Spencer M, Jenkins J, George EL, Thomas JR, Michaud G, Schirle M, Tallarico J, Passmore LA, Chao JA, Beckwith REJ. CPSF3-dependent pre-mRNA processing as a druggable node in AML and Ewing's sarcoma. Nat Chem Biol 2019; 16:50-59. [PMID: 31819276 DOI: 10.1038/s41589-019-0424-1] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 11/01/2019] [Indexed: 02/07/2023]
Abstract
The post-genomic era has seen many advances in our understanding of cancer pathways, yet resistance and tumor heterogeneity necessitate multiple approaches to target even monogenic tumors. Here, we combine phenotypic screening with chemical genetics to identify pre-messenger RNA endonuclease cleavage and polyadenylation specificity factor 3 (CPSF3) as the target of JTE-607, a small molecule with previously unknown target. We show that CPSF3 represents a synthetic lethal node in a subset of acute myeloid leukemia (AML) and Ewing's sarcoma cancer cell lines. Inhibition of CPSF3 by JTE-607 alters expression of known downstream effectors in AML and Ewing's sarcoma lines, upregulates apoptosis and causes tumor-selective stasis in mouse xenografts. Mechanistically, it prevents the release of newly synthesized pre-mRNAs, resulting in read-through transcription and the formation of DNA-RNA hybrid R-loop structures. This study implicates pre-mRNA processing, and specifically CPSF3, as a druggable target providing an avenue to therapeutic intervention in cancer.
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Affiliation(s)
- Nathan T Ross
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA.,Vertex Pharmaceuticals, Boston, MA, USA
| | - Felix Lohmann
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Seth Carbonneau
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Aleem Fazal
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | | | - Scott Gleim
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Michael Salcius
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | | | - Martin Henault
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Sarah H Carl
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
| | | | - Howard R Miller
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | | | - Jason Murphy
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Mark Zambrowski
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | | | - Yuan Wang
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Aye Chen
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | | | - Johannes H Wilbertz
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | | | - Min Jia
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland.,University of Basel, Basel, Switzerland
| | | | - Jonathan Turner
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Judith Knehr
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Walter Carbone
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Sven Schuierer
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | | | - Kevin Xie
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Chitra Saran
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Eric T Williams
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Guglielmo Roma
- Novartis Institutes for BioMedical Research, Basel, Switzerland
| | - Matt Spencer
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Jeremy Jenkins
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | | | - Jason R Thomas
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Gregory Michaud
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Markus Schirle
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - John Tallarico
- Novartis Institutes for BioMedical Research, Cambridge, MA, USA
| | - Lori A Passmore
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Jeffrey A Chao
- Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland
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4
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Palacios DS, Meredith EL, Kawanami T, Adams CM, Chen X, Darsigny V, Palermo M, Baird D, George EL, Guy C, Hewett J, Tierney L, Thigale S, Wang L, Weihofen WA. Scaffold Morphing Identifies 3-Pyridyl Azetidine Ureas as Inhibitors of Nicotinamide Phosphoribosyltransferase (NAMPT). ACS Med Chem Lett 2019; 10:1524-1529. [PMID: 31749905 DOI: 10.1021/acsmedchemlett.9b00325] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 10/10/2019] [Indexed: 11/29/2022] Open
Abstract
Small molecules that inhibit the metabolic enzyme NAMPT have emerged as potential therapeutics in oncology. As part of our effort in this area, we took a scaffold morphing approach and identified 3-pyridyl azetidine ureas as a potent NAMPT inhibiting motif. We explored the SAR of this series, including 5 and 6 amino pyridines, using a convergent synthetic strategy. This lead optimization campaign yielded multiple compounds with excellent in vitro potency and good ADME properties that culminated in compound 27.
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Affiliation(s)
- Daniel S. Palacios
- Global Discovery Chemistry, Novartis Institute for Biomedical Research, 22 Windsor Street, Cambridge, Massachusetts 02139, United States
| | - Erik L. Meredith
- Global Discovery Chemistry, Novartis Institute for Biomedical Research, 22 Windsor Street, Cambridge, Massachusetts 02139, United States
| | - Toshio Kawanami
- Global Discovery Chemistry, Novartis Institute for Biomedical Research, 22 Windsor Street, Cambridge, Massachusetts 02139, United States
| | - Christopher M. Adams
- Global Discovery Chemistry, Novartis Institute for Biomedical Research, 22 Windsor Street, Cambridge, Massachusetts 02139, United States
| | - Xin Chen
- Global Discovery Chemistry, Novartis Institute for Biomedical Research, 22 Windsor Street, Cambridge, Massachusetts 02139, United States
| | - Veronique Darsigny
- Global Discovery Chemistry, Novartis Institute for Biomedical Research, 22 Windsor Street, Cambridge, Massachusetts 02139, United States
| | - Mark Palermo
- Global Discovery Chemistry, Novartis Institute for Biomedical Research, 22 Windsor Street, Cambridge, Massachusetts 02139, United States
| | - Daniel Baird
- Chemical Biology and Therapeutics, Novartis Institute for Biomedical Research, 181 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Elizabeth L. George
- Chemical Biology and Therapeutics, Novartis Institute for Biomedical Research, 181 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Chantale Guy
- Chemical Biology and Therapeutics, Novartis Institute for Biomedical Research, 181 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Jeffrey Hewett
- Chemical Biology and Therapeutics, Novartis Institute for Biomedical Research, 181 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Laryssa Tierney
- Chemical Biology and Therapeutics, Novartis Institute for Biomedical Research, 181 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Sachin Thigale
- Chemical Biology and Therapeutics, Novartis Institute for Biomedical Research, 181 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Louis Wang
- Chemical Biology and Therapeutics, Novartis Institute for Biomedical Research, 181 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Wilhelm A. Weihofen
- Chemical Biology and Therapeutics, Novartis Institute for Biomedical Research, 181 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
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5
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Nolin E, Gans S, Llamas L, Bandyopadhyay S, Brittain SM, Bernasconi-Elias P, Carter KP, Loureiro JJ, Thomas JR, Schirle M, Yang Y, Guo N, Roma G, Schuierer S, Beibel M, Lindeman A, Sigoillot F, Chen A, Xie KX, Ho S, Reece-Hoyes J, Weihofen WA, Tyskiewicz K, Hoepfner D, McDonald RI, Guthrie N, Dogra A, Guo H, Shao J, Ding J, Canham SM, Boynton G, George EL, Kang ZB, Antczak C, Porter JA, Wallace O, Tallarico JA, Palmer AE, Jenkins JL, Jain RK, Bushell SM, Fryer CJ. Discovery of a ZIP7 inhibitor from a Notch pathway screen. Nat Chem Biol 2019; 15:179-188. [PMID: 30643281 DOI: 10.1038/s41589-018-0200-7] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 11/14/2018] [Indexed: 12/15/2022]
Abstract
The identification of activating mutations in NOTCH1 in 50% of T cell acute lymphoblastic leukemia has generated interest in elucidating how these mutations contribute to oncogenic transformation and in targeting the pathway. A phenotypic screen identified compounds that interfere with trafficking of Notch and induce apoptosis via an endoplasmic reticulum (ER) stress mechanism. Target identification approaches revealed a role for SLC39A7 (ZIP7), a zinc transport family member, in governing Notch trafficking and signaling. Generation and sequencing of a compound-resistant cell line identified a V430E mutation in ZIP7 that confers transferable resistance to the compound NVS-ZP7-4. NVS-ZP7-4 altered zinc in the ER, and an analog of the compound photoaffinity labeled ZIP7 in cells, suggesting a direct interaction between the compound and ZIP7. NVS-ZP7-4 is the first reported chemical tool to probe the impact of modulating ER zinc levels and investigate ZIP7 as a novel druggable node in the Notch pathway.
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Affiliation(s)
- Erin Nolin
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA
| | - Sara Gans
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA
| | - Luis Llamas
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA
| | | | | | | | - Kyle P Carter
- Department of Chemistry and Biochemistry and BioFrontiers Institute, University of Colorado, Boulder, CO, USA
| | | | - Jason R Thomas
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA
| | - Markus Schirle
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA
| | - Yi Yang
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA
| | - Ning Guo
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA
| | - Guglielmo Roma
- Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Sven Schuierer
- Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Martin Beibel
- Novartis Institutes for Biomedical Research, Basel, Switzerland
| | - Alicia Lindeman
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA
| | | | - Amy Chen
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA
| | - Kevin X Xie
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA
| | - Samuel Ho
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA
| | | | | | | | | | | | | | - Abhishek Dogra
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA
| | - Haibing Guo
- Novartis Institutes for Biomedical Research, Shanghai, China
| | - Jian Shao
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA
| | - Jian Ding
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA
| | | | - Geoff Boynton
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA
| | | | - Zhao B Kang
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA
| | | | | | - Owen Wallace
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA
| | | | - Amy E Palmer
- Department of Chemistry and Biochemistry and BioFrontiers Institute, University of Colorado, Boulder, CO, USA
| | | | - Rishi K Jain
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA
| | - Simon M Bushell
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA.
| | - Christy J Fryer
- Novartis Institutes for Biomedical Research, Cambridge, MA, USA.
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6
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Guo H, Camargo LM, Yeboah F, Digan ME, Niu H, Pan Y, Reiling S, Soler-Llavina G, Weihofen WA, Wang HR, Shanker YG, Stams T, Bill A. A NMDA-receptor calcium influx assay sensitive to stimulation by glutamate and glycine/D-serine. Sci Rep 2017; 7:11608. [PMID: 28912557 PMCID: PMC5599507 DOI: 10.1038/s41598-017-11947-x] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 09/01/2017] [Indexed: 02/07/2023] Open
Abstract
N-methyl-D-aspartate-receptors (NMDARs) are ionotropic glutamate receptors that function in synaptic transmission, plasticity and cognition. Malfunction of NMDARs has been implicated in a variety of nervous system disorders, making them attractive therapeutic targets. Overexpression of functional NMDAR in non-neuronal cells results in cell death by excitotoxicity, hindering the development of cell-based assays for NMDAR drug discovery. Here we report a plate-based, high-throughput approach to study NMDAR function. Our assay enables the functional study of NMDARs with different subunit composition after activation by glycine/D-serine or glutamate and hence presents the first plate-based, high throughput assay that allows for the measurement of NMDAR function in glycine/D-serine and/or glutamate sensitive modes. This allows to investigate the effect of small molecule modulators on the activation of NMDARs at different concentrations or combinations of the co-ligands. The reported assay system faithfully replicates the pharmacology of the receptor in response to known agonists, antagonists, positive and negative allosteric modulators, as well as the receptor’s sensitivity to magnesium and zinc. We believe that the ability to study the biology of NMDARs rapidly and in large scale screens will enable the identification of novel therapeutics whose discovery has otherwise been hindered by the limitations of existing cell based approaches.
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Affiliation(s)
- Hongqiu Guo
- Novartis Institutes of Biomedical Research, Chemical Biology and Therapeutics, 250 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - L Miguel Camargo
- Novartis Institutes of Biomedical Research, Chemical Biology and Therapeutics, 250 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - Fred Yeboah
- Novartis Institutes of Biomedical Research, Chemical Biology and Therapeutics, 250 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - Mary Ellen Digan
- Novartis Institutes of Biomedical Research, Chemical Biology and Therapeutics, 250 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - Honglin Niu
- Novartis Institutes of Biomedical Research, Chemical Biology and Therapeutics, 250 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - Yue Pan
- Novartis Institutes of Biomedical Research, Global Discovery Chemistry, 181 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - Stephan Reiling
- Novartis Institutes of Biomedical Research, Chemical Biology and Therapeutics, 250 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - Gilberto Soler-Llavina
- Novartis Institutes of Biomedical Research, Neuroscience, 181 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - Wilhelm A Weihofen
- Novartis Institutes of Biomedical Research, Chemical Biology and Therapeutics, 250 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - Hao-Ran Wang
- Novartis Institutes of Biomedical Research, Chemical Biology and Therapeutics, 250 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - Y Gopi Shanker
- Novartis Institutes of Biomedical Research, Neuroscience, 181 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - Travis Stams
- Novartis Institutes of Biomedical Research, Chemical Biology and Therapeutics, 250 Massachusetts Avenue, Cambridge, MA, 02139, USA
| | - Anke Bill
- Novartis Institutes of Biomedical Research, Chemical Biology and Therapeutics, 250 Massachusetts Avenue, Cambridge, MA, 02139, USA.
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7
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Nicoludis JM, Lau SY, Schärfe CPI, Marks DS, Weihofen WA, Gaudet R. Structure and Sequence Analyses of Clustered Protocadherins Reveal Antiparallel Interactions that Mediate Homophilic Specificity. Structure 2015; 23:2087-98. [PMID: 26481813 PMCID: PMC4635037 DOI: 10.1016/j.str.2015.09.005] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 09/14/2015] [Accepted: 09/15/2015] [Indexed: 01/07/2023]
Abstract
Clustered protocadherin (Pcdh) proteins mediate dendritic self-avoidance in neurons via specific homophilic interactions in their extracellular cadherin (EC) domains. We determined crystal structures of EC1-EC3, containing the homophilic specificity-determining region, of two mouse clustered Pcdh isoforms (PcdhγA1 and PcdhγC3) to investigate the nature of the homophilic interaction. Within the crystal lattices, we observe antiparallel interfaces consistent with a role in trans cell-cell contact. Antiparallel dimerization is supported by evolutionary correlations. Two interfaces, located primarily on EC2-EC3, involve distinctive clustered Pcdh structure and sequence motifs, lack predicted glycosylation sites, and contain residues highly conserved in orthologs but not paralogs, pointing toward their biological significance as homophilic interaction interfaces. These two interfaces are similar yet distinct, reflecting a possible difference in interaction architecture between clustered Pcdh subfamilies. These structures initiate a molecular understanding of clustered Pcdh assemblies that are required to produce functional neuronal networks.
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Affiliation(s)
- John M. Nicoludis
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, MA, 02138, USA
| | - Sze-Yi Lau
- Department of Molecular and Cellular Biology, Harvard University, 7 Divinity Avenue, Cambridge, MA, 02138, USA
| | - Charlotta P. I. Schärfe
- Department of Systems Biology, Harvard Medical School, Boston, MA, 02115, USA,Applied Bioinformatics, Department of Computer Science, University of Tübingen, Tübingen, Germany
| | - Debora S. Marks
- Department of Systems Biology, Harvard Medical School, Boston, MA, 02115, USA
| | - Wilhelm A. Weihofen
- Department of Molecular and Cellular Biology, Harvard University, 7 Divinity Avenue, Cambridge, MA, 02138, USA,Correspondence: (R. G.), (W. A.W.)
| | - Rachelle Gaudet
- Department of Molecular and Cellular Biology, Harvard University, 7 Divinity Avenue, Cambridge, MA, 02138, USA,Correspondence: (R. G.), (W. A.W.)
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8
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Sotomayor M, Weihofen WA, Gaudet R, Corey DP. Structures and Simulated Dynamics of a Force-Conveying Cadherin Bond Essential for Inner-Ear Mechanotransduction. Biophys J 2013. [DOI: 10.1016/j.bpj.2012.11.937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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9
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Abstract
The hair-cell tip link, a fine filament directly conveying force to mechanosensitive transduction channels, is composed of two proteins, protocadherin-15 and cadherin-23, whose mutation causes deafness. However, their molecular structure, elasticity, and deafness-related structural defects are unknown. We present crystal structures of the first and second extracellular cadherin repeats of cadherin-23. Overall, structures show typical cadherin folds, but reveal an elongated N terminus that precludes classical cadherin interactions and contributes to an N-terminal Ca(2+)-binding site. The deafness mutation D101G, in the linker region between the repeats, causes a slight bend between repeats and decreases Ca(2+) affinity. Molecular dynamics simulations suggest that cadherin-23 repeats are stiff and that either removing Ca(2+) or mutating Ca(2+)-binding residues reduces rigidity and unfolding strength. The structures define an uncharacterized cadherin family and, with simulations, suggest mechanisms underlying inherited deafness and how cadherin-23 may bind with itself and with protocadherin-15 to form the tip link.
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Affiliation(s)
- Marcos Sotomayor
- Howard Hughes Medical Institute, Department of Neurobiology, Harvard Medical School, Boston, MA 02115, USA
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10
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Artavanis-Tsakonas K, Weihofen WA, Antos JM, Coleman BI, Comeaux CA, Duraisingh MT, Gaudet R, Ploegh HL. Characterization and structural studies of the Plasmodium falciparum ubiquitin and Nedd8 hydrolase UCHL3. J Biol Chem 2009; 285:6857-66. [PMID: 20042598 DOI: 10.1074/jbc.m109.072405] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Like their human hosts, Plasmodium falciparum parasites rely on the ubiquitin-proteasome system for survival. We previously identified PfUCHL3, a deubiquitinating enzyme, and here we characterize its activity and changes in active site architecture upon binding to ubiquitin. We find strong evidence that PfUCHL3 is essential to parasite survival. The crystal structures of both PfUCHL3 alone and in complex with the ubiquitin-based suicide substrate UbVME suggest a rather rigid active site crossover loop that likely plays a role in restricting the size of ubiquitin adduct substrates. Molecular dynamics simulations of the structures and a model of the PfUCHL3-PfNedd8 complex allowed the identification of shared key interactions of ubiquitin and PfNedd8 with PfUCHL3, explaining the dual specificity of this enzyme. Distinct differences observed in ubiquitin binding between PfUCHL3 and its human counterpart make it likely that the parasitic DUB can be selectively targeted while leaving the human enzyme unaffected.
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11
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Pratto F, Cicek A, Weihofen WA, Lurz R, Saenger W, Alonso JC. Streptococcus pyogenes pSM19035 requires dynamic assembly of ATP-bound ParA and ParB on parS DNA during plasmid segregation. Nucleic Acids Res 2008; 36:3676-89. [PMID: 18477635 PMCID: PMC2441792 DOI: 10.1093/nar/gkn170] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The accurate partitioning of Firmicute plasmid pSM19035 at cell division depends on ATP binding and hydrolysis by homodimeric ATPase δ2 (ParA) and binding of ω2 (ParB) to its cognate parS DNA. The 1.83 Å resolution crystal structure of δ2 in a complex with non-hydrolyzable ATPγS reveals a unique ParA dimer assembly that permits nucleotide exchange without requiring dissociation into monomers. In vitro, δ2 had minimal ATPase activity in the absence of ω2 and parS DNA. However, stoichiometric amounts of ω2 and parS DNA stimulated the δ2 ATPase activity and mediated plasmid pairing, whereas at high (4:1) ω2 : δ2 ratios, stimulation of the ATPase activity was reduced and δ2 polymerized onto DNA. Stimulation of the δ2 ATPase activity and its polymerization on DNA required ability of ω2 to bind parS DNA and its N-terminus. In vivo experiments showed that δ2 alone associated with the nucleoid, and in the presence of ω2 and parS DNA, δ2 oscillated between the nucleoid and the cell poles and formed spiral-like structures. Our studies indicate that the molar ω2 : δ2 ratio regulates the polymerization properties of (δ•ATP•Mg2+)2 on and depolymerization from parS DNA, thereby controlling the temporal and spatial segregation of pSM19035 before cell division.
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Affiliation(s)
- Florencia Pratto
- Department of Microbial Biotechnology, National Centre of Biotechnology, CSIC, 28049 Madrid, Spain
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12
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Schlieker C, Weihofen WA, Frijns E, Kattenhorn LM, Gaudet R, Ploegh HL. Structure of a herpesvirus-encoded cysteine protease reveals a unique class of deubiquitinating enzymes. Mol Cell 2007; 25:677-87. [PMID: 17349955 PMCID: PMC7110467 DOI: 10.1016/j.molcel.2007.01.033] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2006] [Revised: 12/04/2006] [Accepted: 01/19/2007] [Indexed: 10/28/2022]
Abstract
All members of the herpesviridae contain within their large tegument protein a cysteine protease module that displays deubiquitinating activity. We report the crystal structure of the cysteine protease domain of murine cytomegalovirus M48 (M48(USP)) in a complex with a ubiquitin (Ub)-based suicide substrate. M48(USP) adopts a papain-like fold, with the active-site cysteine forming a thioether linkage to the suicide substrate. The Ub core participates in an extensive hydrophobic interaction with an exposed beta hairpin loop of M48(USP). This Ub binding mode contributes to Ub specificity and is distinct from that observed in other deubiquitinating enzymes. Both the arrangement of active-site residues and the architecture of the interface with Ub lead us to classify this domain as the founding member of a previously unknown class of deubiquitinating enzymes.
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Affiliation(s)
- Christian Schlieker
- Department of Biology, Whitehead Institute for Biomedical Research, Massachusetts Institute of Technology, 9 Cambridge Center, Cambridge, MA 02142, USA
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13
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Weihofen WA, Berger M, Chen H, Saenger W, Hinderlich S. Structures of human N-Acetylglucosamine kinase in two complexes with N-Acetylglucosamine and with ADP/glucose: insights into substrate specificity and regulation. J Mol Biol 2006; 364:388-99. [PMID: 17010375 DOI: 10.1016/j.jmb.2006.08.085] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2006] [Revised: 08/29/2006] [Accepted: 08/30/2006] [Indexed: 11/15/2022]
Abstract
N-Acetylglucosamine (GlcNAc), a major component of complex carbohydrates, is synthesized de novo or salvaged from lysosomally degraded glycoconjugates and from nutritional sources. The salvage pathway requires that GlcNAc kinase converts GlcNAc to GlcNAc-6-phosphate, a component utilized in UDP-GlcNAc biosynthesis or energy metabolism. GlcNAc kinase belongs to the sugar kinase/Hsp70/actin superfamily that catalyze phosphoryl transfer from ATP to their respective substrates, and in most cases catalysis is associated with a large conformational change in which the N-terminal small and C-terminal large domains enclose the substrates. Here we report two crystal structures of homodimeric human GlcNAc kinase, one in complex with GlcNAc and the other in complex with ADP and glucose. The active site of GlcNAc kinase is located in a deep cleft between the two domains of the V-shaped monomer. The enzyme adopts a "closed" configuration in the GlcNAc-bound complex and GlcNAc interacts with residues of both domains. In addition, the N-acetyl methyl group contacts residues of the other monomer in the homodimer, a unique feature compared to other members of the sugar kinase/Hsp70/actin superfamily. This contrasts an "open" configuration in the ADP/glucose-bound structure, where glucose cannot form these interactions, explaining its low binding affinity for GlcNAc kinase. Our results support functional implications derived from apo crystal structures of GlcNAc kinases from Chromobacter violaceum and Porphyromonas gingivalis and show that Tyr205, which is phosphorylated in thrombin-activated platelets, lines the GlcNAc binding pocket. This suggests that phosphorylation of Tyr205 may modulate GlcNAc kinase activity and/or specificity.
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Affiliation(s)
- Wilhelm A Weihofen
- Freie Universität Berlin, Institut für Chemie und Biochemie-Kristallographie, Takustrasse 6, 14195 Berlin-Dahlem, Germany
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14
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Weihofen WA, Liu J, Reutter W, Saenger W, Fan H. Crystal structure of CD26/dipeptidyl-peptidase IV in complex with adenosine deaminase reveals a highly amphiphilic interface. J Biol Chem 2004; 279:43330-5. [PMID: 15213224 DOI: 10.1074/jbc.m405001200] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Dipeptidyl-peptidase IV (DPPIV or CD26) is a homodimeric type II membrane glycoprotein in which the two monomers are subdivided into a beta-propeller domain and an alpha/beta-hydrolase domain. As dipeptidase, DPPIV modulates the activity of various biologically important peptides and, in addition, DPPIV acts as a receptor for adenosine deaminase (ADA), thereby mediating co-stimulatory signals in T-lymphocytes. The 3.0-A resolution crystal structure of the complex formed between human DPPIV and bovine ADA presented here shows that each beta-propeller domain of the DPPIV dimer binds one ADA. At the binding interface, two hydrophobic loops protruding from the beta-propeller domain of DPPIV interact with two hydrophilic and heavily charged alpha-helices of ADA, giving rise to the highest percentage of charged residues involved in a protein-protein contact reported thus far. Additionally, four glycosides linked to Asn229 of DPPIV bind to ADA. In the crystal structure of porcine DPPIV, the observed tetramer formation was suggested to mediate epithelial and lymphocyte cell-cell adhesion. ADA binding to DPPIV could regulate this adhesion, as it would abolish tetramerization.
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Affiliation(s)
- Wilhelm A Weihofen
- Institut für Chemie/Kristallographie, Freie Universität Berlin, Takustrasse 6, D-14195 Berlin, Germany
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15
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Lenhart A, Weihofen WA, Pleschke AEW, Schulz GE. Crystal structure of a squalene cyclase in complex with the potential anticholesteremic drug Ro48-8071. Chem Biol 2002; 9:639-45. [PMID: 12031670 DOI: 10.1016/s1074-5521(02)00138-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Squalene-hopene cyclase (SHC) catalyzes the conversion of squalene into pentacyclic compounds. It is the prokaryotic counterpart of the eukaryotic oxidosqualene cyclase (OSC) that catalyzes the steroid scaffold formation. Because of clear sequence homology, SHC can serve as a model for OSC, which is an attractive target for anticholesteremic drugs. We have established the crystal structure of SHC complexed with Ro48-8071, a potent inhibitor of OSC and therefore of cholesterol biosynthesis. Ro48-8071 is bound in the active-center cavity of SHC and extends into the channel that connects the cavity with the membrane. The binding site of Ro48-8071 is largely identical with the expected site of squalene; it differs from a previous model based on photoaffinity labeling. The knowledge of the inhibitor binding mode in SHC is likely to help develop more potent inhibitors for OSC.
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Affiliation(s)
- Alexander Lenhart
- Institut für Organische Chemie und Biochemie, Albert-Ludwigs-Universität, D-79104-, Freiburg im Breisgau, Germany
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Milla P, Lenhart A, Grosa G, Viola F, Weihofen WA, Schulz GE, Balliano G. Thiol-modifying inhibitors for understanding squalene cyclase function. Eur J Biochem 2002; 269:2108-16. [PMID: 11985588 DOI: 10.1046/j.1432-1033.2002.02861.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The function of squalene-hopene cyclase from Alicyclobacillus acidocaldarius was studied by labelling critical cysteine residues of the enzyme, either native or inserted by site-directed mutagenesis, with different thiol-reacting molecules. The access of the substrate to the active centre cavity through a nonpolar channel that contains a narrow constriction harbouring a cysteine residue (C435) was probed by labelling experiments on both a C435S mutant, lacking C435 of the channel constriction, and a C25S/C50S/C455S/C537S mutant, bearing C435 as the only cysteine residue. Labelling experiments with tritiated 3-carboxy-4-nitrophenyl-dithio-1,1',2-trisnorsqualene (CNDT-squalene) showed that the cysteine residue at the channel constriction was covalently modified by the squalene-like inhibitor. Time-dependent inactivation of the C25S/C50S/C455S/C537S mutant by a number of squalene analogues and other agents with thiol-modifying activity suggested that modifying C435 caused the obstruction of the channel constriction thus blocking access of the substrate to the active site. The tryptic fragment comprising C435 of the quadruple mutant labelled with the most effective inhibitor had the expected altered molecular mass, as determined by LC-ESI-MS measurements. The arrangement of the substrate in the active site cavity was studied by using thiol reagents as probes in labelling experiments with the double mutant D376C/C435S in which D376, supposedly the substrate-protonating residue, was substituted by cysteine. The inhibitory effect was evaluated in terms of the reduced ability to cyclize oxidosqualene, as the mutant is unable to catalyse the reaction of squalene to hopene. Among the inhibitors tested, the substrate analogue squalene-maleimide proved to be a very effective time-dependent inhibitor.
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Affiliation(s)
- Paola Milla
- Università degli Studi di Torino, Dipartimento di Scienza e Tecnologia del Farmaco, Torino, Italy
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