1
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Khazma T, Grossman A, Guez-Haddad J, Feng C, Dabas H, Sain R, Weitman M, Zalk R, Isupov MN, Hammarlund M, Hons M, Opatowsky Y. Structure-function analysis of ceTIR-1/hSARM1 explains the lack of Wallerian axonal degeneration in C. elegans. Cell Rep 2023; 42:113026. [PMID: 37635352 PMCID: PMC10675840 DOI: 10.1016/j.celrep.2023.113026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Revised: 06/05/2023] [Accepted: 08/09/2023] [Indexed: 08/29/2023] Open
Abstract
Wallerian axonal degeneration (WD) does not occur in the nematode C. elegans, in contrast to other model animals. However, WD depends on the NADase activity of SARM1, a protein that is also expressed in C. elegans (ceSARM/ceTIR-1). We hypothesized that differences in SARM between species might exist and account for the divergence in WD. We first show that expression of the human (h)SARM1, but not ceTIR-1, in C. elegans neurons is sufficient to confer axon degeneration after nerve injury. Next, we determined the cryoelectron microscopy structure of ceTIR-1 and found that, unlike hSARM1, which exists as an auto-inhibited ring octamer, ceTIR-1 forms a readily active 9-mer. Enzymatically, the NADase activity of ceTIR-1 is substantially weaker (10-fold higher Km) than that of hSARM1, and even when fully active, it falls short of consuming all cellular NAD+. Our experiments provide insight into the molecular mechanisms and evolution of SARM orthologs and WD across species.
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Affiliation(s)
- Tami Khazma
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Atira Grossman
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Julia Guez-Haddad
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Chengye Feng
- Departments of Neuroscience and Genetics, Yale School of Medicine, New Haven, CT, USA
| | - Hadas Dabas
- Departments of Neuroscience and Genetics, Yale School of Medicine, New Haven, CT, USA
| | - Radhika Sain
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Michal Weitman
- Department of Chemistry, Bar-Ilan University, Ramat Gan, Israel
| | - Ran Zalk
- Ilse Katz Institute for Nanoscale Science & Technology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Michail N Isupov
- Henry Wellcome Building for Biocatalysis, Biosciences, Faculty of Health and Life Sciences, University of Exeter, Exeter, UK
| | - Marc Hammarlund
- Departments of Neuroscience and Genetics, Yale School of Medicine, New Haven, CT, USA.
| | - Michael Hons
- European Molecular Biology Laboratory, Grenoble, France.
| | - Yarden Opatowsky
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel.
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2
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Makaros Y, Raiff A, Timms RT, Wagh AR, Gueta MI, Bekturova A, Guez-Haddad J, Brodsky S, Opatowsky Y, Glickman MH, Elledge SJ, Koren I. Ubiquitin-independent proteasomal degradation driven by C-degron pathways. Mol Cell 2023; 83:1921-1935.e7. [PMID: 37201526 PMCID: PMC10237035 DOI: 10.1016/j.molcel.2023.04.023] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 03/13/2023] [Accepted: 04/25/2023] [Indexed: 05/20/2023]
Abstract
Although most eukaryotic proteins are targeted for proteasomal degradation by ubiquitination, a subset have been demonstrated to undergo ubiquitin-independent proteasomal degradation (UbInPD). However, little is known about the molecular mechanisms driving UbInPD and the degrons involved. Utilizing the GPS-peptidome approach, a systematic method for degron discovery, we found thousands of sequences that promote UbInPD; thus, UbInPD is more prevalent than currently appreciated. Furthermore, mutagenesis experiments revealed specific C-terminal degrons required for UbInPD. Stability profiling of a genome-wide collection of human open reading frames identified 69 full-length proteins subject to UbInPD. These included REC8 and CDCA4, proteins which control proliferation and survival, as well as mislocalized secretory proteins, suggesting that UbInPD performs both regulatory and protein quality control functions. In the context of full-length proteins, C termini also play a role in promoting UbInPD. Finally, we found that Ubiquilin family proteins mediate the proteasomal targeting of a subset of UbInPD substrates.
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Affiliation(s)
- Yaara Makaros
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Anat Raiff
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Richard T Timms
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, Jeffrey Cheah Biomedical Centre, Cambridge Biomedical Campus, Cambridge, Cambridgeshire CB2 0AW, UK
| | - Ajay R Wagh
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa 3525433, Israel
| | - Mor Israel Gueta
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Aizat Bekturova
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Julia Guez-Haddad
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Sagie Brodsky
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Yarden Opatowsky
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Michael H Glickman
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa 3525433, Israel
| | - Stephen J Elledge
- Department of Genetics, Harvard Medical School, Division of Genetics, Brigham and Women's Hospital, Howard Hughes Medical Institute, Boston, MA 02115, USA
| | - Itay Koren
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel.
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3
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Khazma T, Golan-Vaishenker Y, Guez-Haddad J, Grossman A, Sain R, Weitman M, Plotnikov A, Zalk R, Yaron A, Hons M, Opatowsky Y. Correction: A duplex structure of SARM1 octamers stabilized by a new inhibitor. Cell Mol Life Sci 2023; 80:68. [PMID: 36814037 DOI: 10.1007/s00018-023-04701-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/18/2023] [Indexed: 02/24/2023]
Affiliation(s)
- Tami Khazma
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Yarden Golan-Vaishenker
- Department of Biomolecular Sciences and Department of Molecular Neuroscience, Weizmann Institute of Science, Rehovot, Israel
| | - Julia Guez-Haddad
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Atira Grossman
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Radhika Sain
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Michal Weitman
- Department of Chemistry, Bar-Ilan University, Ramat Gan, Israel
| | - Alexander Plotnikov
- The Nancy and Stephen Grand Israel National Center for Personalized Medicine, Weizmann Institute of Science, Rehovot, Israel
| | - Ran Zalk
- Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Avraham Yaron
- Department of Biomolecular Sciences and Department of Molecular Neuroscience, Weizmann Institute of Science, Rehovot, Israel
| | - Michael Hons
- European Molecular Biology Laboratory, Grenoble, France.
| | - Yarden Opatowsky
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel.
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4
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Khazma T, Golan-Vaishenker Y, Guez-Haddad J, Grossman A, Sain R, Weitman M, Plotnikov A, Zalk R, Yaron A, Hons M, Opatowsky Y. A duplex structure of SARM1 octamers stabilized by a new inhibitor. Cell Mol Life Sci 2022; 80:16. [PMID: 36564647 DOI: 10.1007/s00018-022-04641-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 11/16/2022] [Accepted: 11/19/2022] [Indexed: 12/25/2022]
Abstract
In recent years, there has been growing interest in SARM1 as a potential breakthrough drug target for treating various pathologies of axon degeneration. SARM1-mediated axon degeneration relies on its TIR domain NADase activity, but recent structural data suggest that the non-catalytic ARM domain could also serve as a pharmacological site as it has an allosteric inhibitory function. Here, we screened for synthetic small molecules that inhibit SARM1, and tested a selected set of these compounds in a DRG axon degeneration assay. Using cryo-EM, we found that one of the newly discovered inhibitors, a calmidazolium designated TK106, not only stabilizes the previously reported inhibited conformation of the octamer, but also a meta-stable structure: a duplex of octamers (16 protomers), which we have now determined to 4.0 Å resolution. In the duplex, each ARM domain protomer is engaged in lateral interactions with neighboring protomers, and is further stabilized by contralateral contacts with the opposing octamer ring. Mutagenesis of the duplex contact sites leads to a moderate increase in SARM1 activation in cultured cells. Based on our data we propose that the duplex assembly constitutes an additional auto-inhibition mechanism that tightly prevents pre-mature activation and axon degeneration.
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Affiliation(s)
- Tami Khazma
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | | | - Julia Guez-Haddad
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Atira Grossman
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Radhika Sain
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel
| | - Michal Weitman
- Department of Chemistry, Bar-Ilan University, Ramat Gan, Israel
| | - Alexander Plotnikov
- The Nancy and Stephen Grand Israel National Center for Personalized Medicine, Weizmann Institute of Science, Rehovot, Israel
| | - Ran Zalk
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
- Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer-Sheva, Israel
| | - Avraham Yaron
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Michael Hons
- European Molecular Biology Laboratory, Grenoble, France.
| | - Yarden Opatowsky
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, Israel.
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5
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Maimon R, Ankol L, Gradus Pery T, Altman T, Ionescu A, Weissova R, Ostrovsky M, Tank E, Alexandra G, Shelestovich N, Opatowsky Y, Dori A, Barmada S, Balastik M, Perlson E. A CRMP4-dependent retrograde axon-to-soma death signal in amyotrophic lateral sclerosis. EMBO J 2021; 40:e107586. [PMID: 34190355 PMCID: PMC8408612 DOI: 10.15252/embj.2020107586] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Revised: 05/11/2021] [Accepted: 05/28/2021] [Indexed: 12/13/2022] Open
Abstract
Amyotrophic lateral sclerosis (ALS) is a fatal non-cell-autonomous neurodegenerative disease characterized by the loss of motor neurons (MNs). Mutations in CRMP4 are associated with ALS in patients, and elevated levels of CRMP4 are suggested to affect MN health in the SOD1G93A -ALS mouse model. However, the mechanism by which CRMP4 mediates toxicity in ALS MNs is poorly understood. Here, by using tissue from human patients with sporadic ALS, MNs derived from C9orf72-mutant patients, and the SOD1G93A -ALS mouse model, we demonstrate that subcellular changes in CRMP4 levels promote MN loss in ALS. First, we show that while expression of CRMP4 protein is increased in cell bodies of ALS-affected MN, CRMP4 levels are decreased in the distal axons. Cellular mislocalization of CRMP4 is caused by increased interaction with the retrograde motor protein, dynein, which mediates CRMP4 transport from distal axons to the soma and thereby promotes MN loss. Blocking the CRMP4-dynein interaction reduces MN loss in human-derived MNs (C9orf72) and in ALS model mice. Thus, we demonstrate a novel CRMP4-dependent retrograde death signal that underlies MN loss in ALS.
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Affiliation(s)
- Roy Maimon
- Sackler Faculty of MedicineTel Aviv UniversityTel AvivIsrael
| | - Lior Ankol
- Sackler Faculty of MedicineTel Aviv UniversityTel AvivIsrael
- Sagol School of NeuroscienceTel Aviv UniversityTel AvivIsrael
| | - Tal Gradus Pery
- Sackler Faculty of MedicineTel Aviv UniversityTel AvivIsrael
| | - Topaz Altman
- Sackler Faculty of MedicineTel Aviv UniversityTel AvivIsrael
| | - Ariel Ionescu
- Sackler Faculty of MedicineTel Aviv UniversityTel AvivIsrael
| | - Romana Weissova
- Institue of Physiology of the Czech Academy of SciencesPragueCzech Republic
- Faculty of ScienceCharles UniversityPragueCzech Republic
| | | | - Elizabeth Tank
- Department of NeurologyUniversity of MichiganAnn ArborMIUSA
| | - Gayster Alexandra
- Department of PathologySheba Medical CenterTel HashomerRamat GanIsrael
| | - Natalia Shelestovich
- Sackler Faculty of MedicineTel Aviv UniversityTel AvivIsrael
- Department of PathologySheba Medical CenterTel HashomerRamat GanIsrael
| | - Yarden Opatowsky
- The Mina and Everard Goodman Faculty of Life ScienceBar Ilan UniversityIsrael
| | - Amir Dori
- Sackler Faculty of MedicineTel Aviv UniversityTel AvivIsrael
- Sagol School of NeuroscienceTel Aviv UniversityTel AvivIsrael
- Department of NeurologySheba Medical CenterTel HashomerRamat GanIsrael
| | - Sami Barmada
- Department of NeurologyUniversity of MichiganAnn ArborMIUSA
| | - Martin Balastik
- Institue of Physiology of the Czech Academy of SciencesPragueCzech Republic
| | - Eran Perlson
- Sackler Faculty of MedicineTel Aviv UniversityTel AvivIsrael
- Sagol School of NeuroscienceTel Aviv UniversityTel AvivIsrael
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6
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Sporny M, Guez-Haddad J, Khazma T, Yaron A, Dessau M, Shkolnisky Y, Mim C, Isupov MN, Zalk R, Hons M, Opatowsky Y. Structural basis for SARM1 inhibition and activation under energetic stress. eLife 2020; 9:e62021. [PMID: 33185189 PMCID: PMC7688312 DOI: 10.7554/elife.62021] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 11/12/2020] [Indexed: 12/24/2022] Open
Abstract
SARM1, an executor of axonal degeneration, displays NADase activity that depletes the key cellular metabolite, NAD+, in response to nerve injury. The basis of SARM1 inhibition and its activation under stress conditions are still unknown. Here, we present cryo-EM maps of SARM1 at 2.9 and 2.7 Å resolutions. These indicate that SARM1 homo-octamer avoids premature activation by assuming a packed conformation, with ordered inner and peripheral rings, that prevents dimerization and activation of the catalytic domains. This inactive conformation is stabilized by binding of SARM1's own substrate NAD+ in an allosteric location, away from the catalytic sites. This model was validated by mutagenesis of the allosteric site, which led to constitutively active SARM1. We propose that the reduction of cellular NAD+ concentration contributes to the disassembly of SARM1's peripheral ring, which allows formation of active NADase domain dimers, thereby further depleting NAD+ to cause an energetic catastrophe and cell death.
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Affiliation(s)
- Michael Sporny
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan UniversityRamat-GanIsrael
| | - Julia Guez-Haddad
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan UniversityRamat-GanIsrael
| | - Tami Khazma
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan UniversityRamat-GanIsrael
| | - Avraham Yaron
- Department of Biomolecular Sciences, Weizmann Institute of ScienceRehovotIsrael
| | - Moshe Dessau
- Azrieli Faculty of Medicine, Bar Ilan UniversitySafedIsrael
| | - Yoel Shkolnisky
- Department of Applied Mathematics, School of Mathematical Sciences, Tel-Aviv UniversityTel-AvivIsrael
| | - Carsten Mim
- Royal Technical Institute (KTH), Dept. For Biomedical Engineering and Health SystemsStockholmSweden
| | | | - Ran Zalk
- National Institute for Biotechnology in the Negev, Ben-Gurion University of the NegevBeer-ShevaIsrael
| | - Michael Hons
- European Molecular Biology LaboratoryGrenobleFrance
| | - Yarden Opatowsky
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan UniversityRamat-GanIsrael
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7
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Sporny M, Guez-Haddad J, Lebendiker M, Ulisse V, Volf A, Mim C, Isupov MN, Opatowsky Y. Structural Evidence for an Octameric Ring Arrangement of SARM1. J Mol Biol 2019; 431:3591-3605. [PMID: 31278906 DOI: 10.1016/j.jmb.2019.06.030] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 06/16/2019] [Accepted: 06/25/2019] [Indexed: 12/11/2022]
Abstract
SARM1 induces axonal degeneration in response to various insults and is therefore considered an attractive drug target for the treatment of neuro-degenerative diseases as well as for brain and spinal cord injuries. SARM1 activity depends on the integrity of the protein's SAM domains, as well as on the enzymatic conversion of NAD+ to ADPR (ADP Ribose) products by the SARM1's TIR domain. Therefore, inhibition of either SAM or TIR functions may constitute an effective therapeutic strategy. However, there is currently no SARM1-directed therapeutic approach available because of an insufficient structural and mechanistic understanding of this protein. In this study, we found that SARM1 assembles into an octameric ring. This arrangement was not described before in other SAM proteins, but is reminiscent of the apoptosome and inflammasome-well-known apoptotic ring-like oligomers. We show that both SARM1 and the isolated tandem SAM1-2 domains form octamers in solution, and electron microscopy analysis reveals an octameric ring of SARM1. We determined the crystal structure of SAM1-2 and found that it also forms a closed octameric ring in the crystal lattice. The SAM1-2 ring interactions are mediated by complementing "lock and key" hydrophobic grooves and inserts and electrostatic charges between the neighboring protomers. We have mutated several interacting SAM1-2 interfaces and measured how these mutations affect SARM1 apoptotic activity in cultured cells, and in this way identified critical oligomerization sites that facilitate cell death. These results highlight the importance of oligomerization for SARM1 function and reveal critical epitopes for future targeted drug development.
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Affiliation(s)
- Michael Sporny
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Julia Guez-Haddad
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Mario Lebendiker
- Wolfson Centre for Applied Structural Biology, The Hebrew University of Jerusalem, Israel
| | - Valeria Ulisse
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Allison Volf
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Carsten Mim
- Department of Biomedical Engineering and Health Solutions, Royal Technical Institute (KTH), Stockholm, Sweden; Department of Nutrition and Biosciences, Karolinska Institute, Huddinge, Sweden
| | | | - Yarden Opatowsky
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel.
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8
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Barak R, Yom-Tov G, Guez-Haddad J, Gasri-Plotnitsky L, Maimon R, Cohen-Berkman M, McCarthy AA, Perlson E, Henis-Korenblit S, Isupov MN, Opatowsky Y. Structural Principles in Robo Activation and Auto-inhibition. Cell 2019; 177:272-285.e16. [PMID: 30853216 DOI: 10.1016/j.cell.2019.02.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [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: 09/02/2018] [Revised: 12/06/2018] [Accepted: 02/06/2019] [Indexed: 01/28/2023]
Abstract
Proper brain function requires high-precision neuronal expansion and wiring, processes controlled by the transmembrane Roundabout (Robo) receptor family and their Slit ligands. Despite their great importance, the molecular mechanism by which Robos' switch from "off" to "on" states remains unclear. Here, we report a 3.6 Å crystal structure of the intact human Robo2 ectodomain (domains D1-8). We demonstrate that Robo cis dimerization via D4 is conserved through hRobo1, 2, and 3 and the C. elegans homolog SAX-3 and is essential for SAX-3 function in vivo. The structure reveals two levels of auto-inhibition that prevent premature activation: (1) cis blocking of the D4 dimerization interface and (2) trans interactions between opposing Robo receptors that fasten the D4-blocked conformation. Complementary experiments in mouse primary neurons and C. elegans support the auto-inhibition model. These results suggest that Slit stimulation primarily drives the release of Robo auto-inhibition required for dimerization and activation.
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Affiliation(s)
- Reut Barak
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Israel
| | - Galit Yom-Tov
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Israel
| | - Julia Guez-Haddad
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Israel
| | | | - Roy Maimon
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Israel
| | - Moran Cohen-Berkman
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Israel
| | | | - Eran Perlson
- Department of Physiology and Pharmacology, Sackler Faculty of Medicine, Tel Aviv University, Israel
| | | | | | - Yarden Opatowsky
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Israel.
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9
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Ren C, Yuan Q, Braun M, Zhang X, Petri B, Zhang J, Kim D, Guez-Haddad J, Xue W, Pan W, Fan R, Kubes P, Sun Z, Opatowsky Y, Polleux F, Karatekin E, Tang W, Wu D. Leukocyte Cytoskeleton Polarization Is Initiated by Plasma Membrane Curvature from Cell Attachment. Dev Cell 2019; 49:206-219.e7. [PMID: 30930167 DOI: 10.1016/j.devcel.2019.02.023] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Revised: 01/15/2019] [Accepted: 02/25/2019] [Indexed: 12/30/2022]
Abstract
Cell polarization is important for various biological processes. However, its regulation, particularly initiation, is incompletely understood. Here, we investigated mechanisms by which neutrophils break their symmetry and initiate their cytoskeleton polarization from an apolar state in circulation for their extravasation during inflammation. We show here that a local increase in plasma membrane (PM) curvature resulting from cell contact to a surface triggers the initial breakage of the symmetry of an apolar neutrophil and is required for subsequent polarization events induced by chemical stimulation. This local increase in PM curvature recruits SRGAP2 via its F-BAR domain, which in turn activates PI4KA and results in PM PtdIns4P polarization. Polarized PM PtdIns4P is targeted by RPH3A, which directs PIP5K1C90 and subsequent phosphorylated myosin light chain polarization, and this polarization signaling axis regulates neutrophil firm attachment to endothelium. Thus, this study reveals a mechanism for the initiation of cell cytoskeleton polarization.
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Affiliation(s)
- Chunguang Ren
- Department of Pharmacology, Vascular Biology and Therapeutic Program, Yale University, New Haven, CT 06520, USA
| | - Qianying Yuan
- Department of Pharmacology, Vascular Biology and Therapeutic Program, Yale University, New Haven, CT 06520, USA
| | - Martha Braun
- Department of Cellular and Molecular Physiology, Yale University, New Haven, CT 06520, USA; Nanobiology Institute, Yale University, New Haven, CT 06520, USA; Department of Molecular Biophysics and Biochemistry, Yale School of Medicine, Yale University, New Haven, CT 06520, USA
| | - Xia Zhang
- Department of Geriatrics, the First affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Björn Petri
- Snyder Institute for Chronic Diseases Mouse Phenomics Resource Laboratory, University of Calgary, Calgary AB T2N 4N1, Canada; Department of Microbiology, Immunology, and Infectious Diseases, University of Calgary, Calgary AB T2N 4N1, Canada
| | - Jiasheng Zhang
- Department of Internal Medicine, Yale University, New Haven, CT 06520, USA
| | - Dongjoo Kim
- Department of Biomedical Engineering, Yale University, New Haven, CT 06520, USA
| | - Julia Guez-Haddad
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Wenzhi Xue
- Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences (CAS), Shanghai, China
| | - Weijun Pan
- Shanghai Institute of Nutrition and Health, Shanghai Institutes for Biological Sciences, University of Chinese Academy of Sciences, Chinese Academy of Sciences (CAS), Shanghai, China
| | - Rong Fan
- Department of Biomedical Engineering, Yale University, New Haven, CT 06520, USA
| | - Paul Kubes
- Snyder Institute for Chronic Diseases Mouse Phenomics Resource Laboratory, University of Calgary, Calgary AB T2N 4N1, Canada; Department of Physiology and Pharmacology, Cumming School of Medicine, and Calvin, Phoebe, and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary AB T2N 4N1, Canada
| | - Zhaoxia Sun
- Department of Genetics, Yale University, New Haven, CT 06520, USA
| | - Yarden Opatowsky
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Franck Polleux
- Department of Neuroscience, Mortimer B. Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10025, USA
| | - Erdem Karatekin
- Department of Cellular and Molecular Physiology, Yale University, New Haven, CT 06520, USA; Nanobiology Institute, Yale University, New Haven, CT 06520, USA; Department of Molecular Biophysics and Biochemistry, Yale School of Medicine, Yale University, New Haven, CT 06520, USA; Centre National de la Recherche Scientifique (CNRS), Paris, France.
| | - Wenwen Tang
- Department of Pharmacology, Vascular Biology and Therapeutic Program, Yale University, New Haven, CT 06520, USA.
| | - Dianqing Wu
- Department of Pharmacology, Vascular Biology and Therapeutic Program, Yale University, New Haven, CT 06520, USA.
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10
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Sporny M, Guez-Haddad J, Kreusch A, Shakartzi S, Neznansky A, Cross A, Isupov MN, Qualmann B, Kessels MM, Opatowsky Y. Structural History of Human SRGAP2 Proteins. Mol Biol Evol 2017; 34:1463-1478. [PMID: 28333212 PMCID: PMC5435084 DOI: 10.1093/molbev/msx094] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
In the development of the human brain, human-specific genes are considered to play key roles, conferring its unique advantages and vulnerabilities. At the time of Homo lineage divergence from Australopithecus, SRGAP2C gradually emerged through a process of serial duplications and mutagenesis from ancestral SRGAP2A (3.4–2.4 Ma). Remarkably, ectopic expression of SRGAP2C endows cultured mouse brain cells, with human-like characteristics, specifically, increased dendritic spine length and density. To understand the molecular mechanisms underlying this change in neuronal morphology, we determined the structure of SRGAP2A and studied the interplay between SRGAP2A and SRGAP2C. We found that: 1) SRGAP2A homo-dimerizes through a large interface that includes an F-BAR domain, a newly identified F-BAR extension (Fx), and RhoGAP-SH3 domains. 2) SRGAP2A has an unusual inverse geometry, enabling associations with lamellipodia and dendritic spine heads in vivo, and scaffolding of membrane protrusions in cell culture. 3) As a result of the initial partial duplication event (∼3.4 Ma), SRGAP2C carries a defective Fx-domain that severely compromises its solubility and membrane-scaffolding ability. Consistently, SRGAP2A:SRAGP2C hetero-dimers form, but are insoluble, inhibiting SRGAP2A activity. 4) Inactivation of SRGAP2A is sensitive to the level of hetero-dimerization with SRGAP2C. 5) The primal form of SRGAP2C (P-SRGAP2C, existing between ∼3.4 and 2.4 Ma) is less effective in hetero-dimerizing with SRGAP2A than the modern SRGAP2C, which carries several substitutions (from ∼2.4 Ma). Thus, the genetic mutagenesis phase contributed to modulation of SRGAP2A’s inhibition of neuronal expansion, by introducing and improving the formation of inactive SRGAP2A:SRGAP2C hetero-dimers, indicating a stepwise involvement of SRGAP2C in human evolutionary history.
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Affiliation(s)
- Michael Sporny
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
| | - Julia Guez-Haddad
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
| | - Annett Kreusch
- Institute for Biochemistry I, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany
| | - Sivan Shakartzi
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
| | - Avi Neznansky
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
| | - Alice Cross
- Department of Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Michail N Isupov
- Department of Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Britta Qualmann
- Institute for Biochemistry I, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany
| | - Michael M Kessels
- Institute for Biochemistry I, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany
| | - Yarden Opatowsky
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
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11
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Yom-Tov G, Barak R, Matalon O, Barda-Saad M, Guez-Haddad J, Opatowsky Y. Robo Ig4 Is a Dimerization Domain. J Mol Biol 2017; 429:3606-3616. [PMID: 29017837 DOI: 10.1016/j.jmb.2017.10.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 10/02/2017] [Accepted: 10/02/2017] [Indexed: 01/06/2023]
Abstract
Robo receptors play pivotal roles in axonal guidance as well as in neurogenesis, angiogenesis, cell migration, and cancer progression and invasiveness. They are considered to be attractive drug targets for the treatment of cancer, ocular neovascular disorders, chronic kidney diseases, and more. Despite their great importance, the mechanisms by which Robo receptors switch from their "off" to "on" states remain obscure. One possibility involves a monomer-to-dimer or dimer-to-monomer transition that facilitates the recruitment and activation of enzymatic effectors to instigate intracellular signaling. However, it is not known which domains mediate Robo dimerization, or the structural properties of the dimeric interactions. Here, we identify the extracellular Ig4 (D4) as a Robo dimerization domain. We have determined the crystal structure of the tandem Ig4-5 domains (D4-5) of human Robo2 and found that a hydrophobic surface on D4 mediates close homotypic contacts with a reciprocal D4. Analytical ultracentrifugation measurements of intact and mutated D4-5 shows that dimerization through the D4 interface is specific and has a dimerization dissociation constant of 16.9μM in solution. Direct fluorescence resonance energy transfer dimerization measurements in HEK293 cells corroborate the dimerization of transmembrane hRobo2 through D4, and a functional COS-7 cell collapse assay links D4-mediated dimerization with Robo intracellular signaling. The high level of conservation in the D4 dimerization interface throughout all Robo orthologs and paralogs implies that D4-mediated dimerization is a central hallmark in Robo activation and signaling.
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Affiliation(s)
- Galit Yom-Tov
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Reut Barak
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Omri Matalon
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Mira Barda-Saad
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Julia Guez-Haddad
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Yarden Opatowsky
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel.
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12
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Sporny M, Guez-Haddad J, Waterman DG, Isupov MN, Opatowsky Y. Molecular symmetry-constrained systematic search approach to structure solution of the coiled-coil SRGAP2 F-BARx domain. Acta Crystallogr D Struct Biol 2016; 72:1241-1253. [PMID: 27917825 DOI: 10.1107/s2059798316016697] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2016] [Accepted: 10/18/2016] [Indexed: 02/05/2023]
Abstract
SRGAP2 (Slit-Robo GTPase-activating protein 2) is a cytoplasmic protein found to be involved in neuronal branching, restriction of neuronal migration and restriction of the length and density of dendritic postsynaptic spines. The extended F-BAR (F-BARx) domain of SRGAP2 generates membrane protrusions when expressed in COS-7 cells, while most F-BARs induce the opposite effect: membrane invaginations. As a first step to understand this discrepancy, the F-BARx domain of SRGAP2 was isolated and crystallized after co-expression with the carboxy domains of the protein. Diffraction data were collected from two significantly non-isomorphous crystals in the same monoclinic C2 space group. A correct molecular-replacment solution was obtained by applying a molecular symmetry-constrained systematic search approach that took advantage of the conserved biological symmetry of the F-BAR domains. It is shown that similar approaches can solve other F-BAR structures that were previously determined by experimental phasing. Diffraction data were reprocessed with a high-resolution cutoff of 2.2 Å, chosen using less strict statistical criteria. This has improved the outcome of multi-crystal averaging and other density-modification procedures.
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Affiliation(s)
- Michael Sporny
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel
| | - Julia Guez-Haddad
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel
| | | | | | - Yarden Opatowsky
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel
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13
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Domankevich V, Opatowsky Y, Malik A, Korol AB, Frenkel Z, Manov I, Avivi A, Shams I. Adaptive patterns in the p53 protein sequence of the hypoxia- and cancer-tolerant blind mole rat Spalax. BMC Evol Biol 2016; 16:177. [PMID: 27590526 PMCID: PMC5010716 DOI: 10.1186/s12862-016-0743-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Accepted: 08/17/2016] [Indexed: 12/19/2022] Open
Abstract
Background The subterranean blind mole rat, Spalax (genus Nannospalax) endures extreme hypoxic conditions and fluctuations in oxygen levels that threaten DNA integrity. Nevertheless, Spalax is long-lived, does not develop spontaneous cancer, and exhibits an outstanding resistance to carcinogenesis in vivo, as well as anti-cancer capabilities in vitro. We hypothesized that adaptations to similar extreme environmental conditions involve common mechanisms for overcoming stress-induced DNA damage. Therefore, we aimed to identify shared features among species that are adapted to hypoxic stress in the sequence of the tumor-suppressor protein p53, a master regulator of the DNA-damage response (DDR). Results We found that the sequences of p53 transactivation subdomain 2 (TAD2) and tetramerization and regulatory domains (TD and RD) are more similar among hypoxia-tolerant species than expected from phylogeny. Specific positions in these domains composed patterns that are more frequent in hypoxia-tolerant species and have proven to be good predictors of species’ classification into stress-related categories. Some of these positions, which are known to be involved in the interactions between p53 and critical DDR proteins, were identified as positively selected. By 3D modeling of p53 interactions with the coactivator p300 and the DNA repair protein RPA70, we demonstrated that, compared to humans, these substitutions potentially reduce the binding of these proteins to Spalax p53. Conclusions We conclude that extreme hypoxic conditions may have led to convergent evolutionary adaptations of the DDR via TAD2 and TD/RD domains of p53. Electronic supplementary material The online version of this article (doi:10.1186/s12862-016-0743-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Vered Domankevich
- Institute of Evolution & Department of Evolutionary and Environmental Biology, University of Haifa, Haifa, Israel
| | - Yarden Opatowsky
- Mina and Everard Goodman Faculty of Life Sciences and Advanced Materials and Nanotechnology Institute, Bar-Ilan University, Ramat-Gan, Israel
| | - Assaf Malik
- Institute of Evolution & Department of Evolutionary and Environmental Biology, University of Haifa, Haifa, Israel
| | - Abraham B Korol
- Institute of Evolution & Department of Evolutionary and Environmental Biology, University of Haifa, Haifa, Israel
| | - Zeev Frenkel
- Institute of Evolution & Department of Evolutionary and Environmental Biology, University of Haifa, Haifa, Israel
| | - Irena Manov
- Institute of Evolution & Department of Evolutionary and Environmental Biology, University of Haifa, Haifa, Israel
| | - Aaron Avivi
- Institute of Evolution & Department of Evolutionary and Environmental Biology, University of Haifa, Haifa, Israel
| | - Imad Shams
- Institute of Evolution & Department of Evolutionary and Environmental Biology, University of Haifa, Haifa, Israel.
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14
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Reshetnyak AV, Opatowsky Y, Boggon TJ, Folta-Stogniew E, Tome F, Lax I, Schlessinger J. The strength and cooperativity of KIT ectodomain contacts determine normal ligand-dependent stimulation or oncogenic activation in cancer. Mol Cell 2014; 57:191-201. [PMID: 25544564 DOI: 10.1016/j.molcel.2014.11.021] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Revised: 10/14/2014] [Accepted: 11/18/2014] [Indexed: 12/22/2022]
Abstract
The receptor tyrosine kinase KIT plays an important role in development of germ cells, hematopoietic cells, and interstitial pacemaker cells. Oncogenic KIT mutations play an important "driver" role in gastrointestinal stromal tumors, acute myeloid leukemias, and melanoma, among other cancers. Here we describe the crystal structure of a recurring somatic oncogenic mutation located in the C-terminal Ig-like domain (D5) of the ectodomain, rendering KIT tyrosine kinase activity constitutively activated. The structural analysis, together with biochemical and biophysical experiments and detailed analyses of the activities of a variety of oncogenic KIT mutations, reveals that the strength of homotypic contacts and the cooperativity in the action of D4D5 regions determines whether KIT is normally regulated or constitutively activated in cancers. We propose that cooperative interactions mediated by multiple weak homotypic contacts between receptor molecules are responsible for regulating normal ligand-dependent or oncogenic RTK activation via a "zipper-like" mechanism for receptor activation.
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Affiliation(s)
- Andrey V Reshetnyak
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Yarden Opatowsky
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Titus J Boggon
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Ewa Folta-Stogniew
- The Biophysical Resource, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Francisco Tome
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA
| | - Irit Lax
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA.
| | - Joseph Schlessinger
- Department of Pharmacology, Yale University School of Medicine, New Haven, CT 06520, USA.
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15
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Neznansky A, Blus-Kadosh I, Yerushalmi G, Banin E, Opatowsky Y. The Pseudomonas aeruginosa phosphate transport protein PstS plays a phosphate-independent role in biofilm formation. FASEB J 2014; 28:5223-33. [PMID: 25223609 DOI: 10.1096/fj.14-258293] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Pseudomonas aeruginosa (PA) is a primary cause of nosocomial infections. A key element in PA pathogenicity is its ability to form biofilms that withstand eradication by antibiotics and the immune system. Biofilm formation is controlled by phosphate signaling and here we provide evidence that PstS, a subunit of the PA Pst phosphate transporter, has a surprising role in this process. Using X-ray crystallography, we characterized the unique underpinnings of PstS phosphate binding and identified an unusual 15-residue N' loop extension. Structure-based experiments showed that PstS-mediated phosphate uptake and biofilm formation are in fact two distinct functions. Specifically, a point mutation that abrogated phosphate binding did not eliminate biofilm formation; conversely, truncation of the N' loop diminished the ability of PA to form biofilms but had no effect on phosphate binding and uptake. This places PstS at a junction that separately controls phosphate sensing and uptake and the ultrastructure organization of bacteria.
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Affiliation(s)
- Avi Neznansky
- Mina and Everard Goodman Faculty of Life Sciences and
| | - Inna Blus-Kadosh
- Mina and Everard Goodman Faculty of Life Sciences and Advanced Materials and Nanotechnology Institute, Bar-Ilan University, Ramat-Gan, Israel
| | - Gal Yerushalmi
- Mina and Everard Goodman Faculty of Life Sciences and Advanced Materials and Nanotechnology Institute, Bar-Ilan University, Ramat-Gan, Israel
| | - Ehud Banin
- Mina and Everard Goodman Faculty of Life Sciences and Advanced Materials and Nanotechnology Institute, Bar-Ilan University, Ramat-Gan, Israel
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16
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Neznansky A, Opatowsky Y. Expression, purification and crystallization of the phosphate-binding PstS protein from Pseudomonas aeruginosa. Acta Crystallogr F Struct Biol Commun 2014; 70:906-10. [PMID: 25005086 PMCID: PMC4089529 DOI: 10.1107/s2053230x14010279] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2014] [Accepted: 05/06/2014] [Indexed: 11/10/2022] Open
Abstract
Pseudomonas aeruginosa (PA) infections pose a serious threat to human health. PA is a leading cause of fatal lung infections in cystic fibrosis and immune-suppressed patients, of sepsis in burn victims and of nosocomial infections. An important element in PA virulence is its ability to establish biofilms that evade suppression by the host's immune system and antibiotics. PstS, a periplasmic subunit of the Pst phosphate-transport system of PA, plays a critical role in the establishment of biofilms. In some drug-resistant PA strains, PstS is secreted in large quantities from the bacteria, where it participates in the assembly of adhesion fibres that enhance bacterial virulence. In order to understand the dual function of PstS in biofilm formation and phosphate transport, the crystal structure of PA PstS was determined. Here, the overexpression in Escherichia coli and purification of PA PstS in the presence of phosphate are described. Two crystal forms were obtained using the vapour-diffusion method at 20°C and X-ray diffraction data were collected. The first crystal form belonged to the centred orthorhombic space group C222₁, with unit-cell parameters a=67.5, b=151.3, c=108.9 Å. Assuming the presence of a dimer in the asymmetric unit gives a crystal volume per protein weight (VM) of 2.09 Å3 Da(-1) and a solvent content of 41%. The second crystal form belonged to the primitive orthorhombic space group P2₁2₁2₁, with unit-cell parameters a=35.4, b=148.3, c=216.7 Å. Assuming the presence of a tetramer in the asymmetric unit gives a crystal volume per protein weight (VM) of 2.14 Å3 Da(-1) and a solvent content of 42.65%. A pseudo-translational symmetry is present in the P212121 crystal form which is consistent with a filamentous arrangement of PstS in the crystal lattice.
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Affiliation(s)
- Avi Neznansky
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel
| | - Yarden Opatowsky
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel
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17
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Barak R, Lahmi R, Gevorkyan-Airapetov L, Levy E, Tzur A, Opatowsky Y. Crystal structure of the extracellular juxtamembrane region of Robo1. J Struct Biol 2014; 186:283-91. [PMID: 24607414 DOI: 10.1016/j.jsb.2014.02.019] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Revised: 02/26/2014] [Accepted: 02/28/2014] [Indexed: 12/17/2022]
Abstract
Robo receptors play pivotal roles in neurodevelopment, and their deregulation is implicated in several neuropathological conditions and cancers. To date, the mechanism of Robo activation and regulation remains obscure. Here we present the crystal structure of the juxtamembrane (JM) domains of human Robo1. The structure exhibits unexpectedly high backbone similarity to the netrin and RGM binding region of neogenin and DCC, which are functionally related receptors of Robo1. Comparison of these structures reveals a conserved surface that overlaps with a cluster of oncogenic and neuropathological mutations found in all Robo isoforms. The structure also reveals the intricate folding of the JM linker, which points to its role in Robo1 activation. Further experiments with cultured cells demonstrate that exposure or relief of the folded JM linker results in enhanced shedding of the Robo1 ectodomain.
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Affiliation(s)
- Reut Barak
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Roxane Lahmi
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel; Advanced Materials and Nanotechnology Institute, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Lada Gevorkyan-Airapetov
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Eliad Levy
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Amit Tzur
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel; Advanced Materials and Nanotechnology Institute, Bar-Ilan University, Ramat-Gan 5290002, Israel
| | - Yarden Opatowsky
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 5290002, Israel.
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18
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Barak R, Opatowsky Y. Expression, derivatization, crystallization and experimental phasing of an extracellular segment of the human Robo1 receptor. Acta Crystallogr Sect F Struct Biol Cryst Commun 2013; 69:771-5. [PMID: 23832205 PMCID: PMC3702322 DOI: 10.1107/s1744309113014863] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Accepted: 05/29/2013] [Indexed: 01/23/2023]
Abstract
Robo receptors participate in the orchestration of several developmental responses, most notably axonal guidance in the central nervous system. Robo1 contains five tandem Ig-like and three fibronectin type-III (FnIII) domains in its ectodomain, followed by a single-pass transmembrane segment and an intracellular region. A human Robo1 construct that includes the two extracellular membrane-proximal fibronectin (Fn) domains and the juxtamembrane linker was overexpressed in Escherichia coli and purified. Crystals were obtained using the vapour-diffusion method at 293 K and X-ray diffraction data were collected. Molecular-replacement attempts using related Fn domains as search models did not result in a solution. After introducing two additional methionine residues using PCR site-directed mutagenesis, selenomethionine-derivative crystals were produced. These crystals belonged to the primitive orthorhombic space group P212121, with unit-cell parameters a = 27.24, b = 77.64, c = 91.91 Å. Assuming the presence of a monomer in the asymmetric unit gave a crystal volume per protein weight (VM) of 1.97 Å(3) Da(-1) and a solvent content of 37.6%. Anisotropic diffraction data and a fragmented single-wavelength anomalous dispersion electron-density map, to which homology-modelled domains were docked, were obtained.
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Affiliation(s)
- Reut Barak
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, 52900 Ramat-Gan, Israel
| | - Yarden Opatowsky
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, 52900 Ramat-Gan, Israel
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19
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Margulies D, Opatowsky Y, Fletcher S, Saraogi I, Tsou LK, Saha S, Lax I, Schlessinger J, Hamilton AD. Surface binding inhibitors of the SCF-KIT protein-protein interaction. Chembiochem 2009; 10:1955-8. [PMID: 19637142 DOI: 10.1002/cbic.200900079] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Affiliation(s)
- David Margulies
- Department of Chemistry, Yale University, New Haven, CT 06520-8107 (USA)
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20
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Yuzawa S, Opatowsky Y, Zhang Z, Mandiyan V, Lax I, Schlessinger J. Structural basis for activation of the receptor tyrosine kinase KIT by stem cell factor. Cell 2007; 130:323-34. [PMID: 17662946 DOI: 10.1016/j.cell.2007.05.055] [Citation(s) in RCA: 248] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2007] [Revised: 04/25/2007] [Accepted: 05/22/2007] [Indexed: 01/15/2023]
Abstract
Stem Cell Factor (SCF) initiates its multiple cellular responses by binding to the ectodomain of KIT, resulting in tyrosine kinase activation. We describe the crystal structure of the entire ectodomain of KIT before and after SCF stimulation. The structures show that KIT dimerization is driven by SCF binding whose sole role is to bring two KIT molecules together. Receptor dimerization is followed by conformational changes that enable lateral interactions between membrane proximal Ig-like domains D4 and D5 of two KIT molecules. Experiments with cultured cells show that KIT activation is compromised by point mutations in amino acids critical for D4-D4 interaction. Moreover, a variety of oncogenic mutations are mapped to the D5-D5 interface. Since key hallmarks of KIT structures, ligand-induced receptor dimerization, and the critical residues in the D4-D4 interface, are conserved in other receptors, the mechanism of KIT stimulation unveiled in this report may apply for other receptor activation.
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Affiliation(s)
- Satoru Yuzawa
- Department of Pharmacology, Yale University School of Medicine, 333 Cedar Street, New Haven, CT 06520, USA
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21
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Opatowsky Y, Sasson Y, Shaked I, Ward Y, Chomsky-Hecht O, Litvak Y, Selinger Z, Kelly K, Hirsch JA. Structure-function studies of the G-domain from human gem, a novel small G-protein. FEBS Lett 2006; 580:5959-64. [PMID: 17052716 PMCID: PMC1934412 DOI: 10.1016/j.febslet.2006.09.067] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2006] [Revised: 09/14/2006] [Accepted: 09/28/2006] [Indexed: 10/24/2022]
Abstract
Gem, a member of the Rad,Gem/Kir subfamily of small G-proteins, has unique sequence features. We report here the crystallographic structure determination of the Gem G-domain in complex with nucleotide to 2.4 A resolution. Although the basic Ras protein fold is maintained, the Gem switch regions emphatically differ from the Ras paradigm. Our ensuing biochemical characterization indicates that Gem G-domain markedly prefers GDP over GTP. Two known functions of Gem are distinctly affected by spatially separated clusters of mutations.
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Affiliation(s)
- Yarden Opatowsky
- Department of Biochemistry, Faculty of Life Sciences, Daniella Rich Institute for Structural Biology, Tel Aviv University, Ramat Aviv 69978, Israel
| | - Yehezkel Sasson
- Department of Biochemistry, Faculty of Life Sciences, Daniella Rich Institute for Structural Biology, Tel Aviv University, Ramat Aviv 69978, Israel
| | - Isabella Shaked
- Department of Biochemistry, Faculty of Life Sciences, Daniella Rich Institute for Structural Biology, Tel Aviv University, Ramat Aviv 69978, Israel
| | - Yvona Ward
- Cell and Cancer Biology Branch, Center for Cancer Research, NCI, NIH, Bethesda, MD, USA
| | - Orna Chomsky-Hecht
- Department of Biochemistry, Faculty of Life Sciences, Daniella Rich Institute for Structural Biology, Tel Aviv University, Ramat Aviv 69978, Israel
| | - Yael Litvak
- Department of Biological Chemistry, Institute of Life Sciences, The Hebrew University, Jerusalem, Israel
| | - Zvi Selinger
- Department of Biological Chemistry, Institute of Life Sciences, The Hebrew University, Jerusalem, Israel
| | - Kathleen Kelly
- Cell and Cancer Biology Branch, Center for Cancer Research, NCI, NIH, Bethesda, MD, USA
| | - Joel A. Hirsch
- Department of Biochemistry, Faculty of Life Sciences, Daniella Rich Institute for Structural Biology, Tel Aviv University, Ramat Aviv 69978, Israel
- *Corresponding author. Fax: +972 3 6407931., E-mail address: (J.A. Hirsch)
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Opatowsky Y, Chomsky-Hecht O, Hirsch JA. Expression, purification and crystallization of a functional core of the voltage-dependent calcium channel β subunit. Acta Crystallogr D Biol Crystallogr 2004; 60:1301-3. [PMID: 15213399 DOI: 10.1107/s0907444904010686] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2004] [Accepted: 05/02/2004] [Indexed: 11/11/2022]
Abstract
Two versions of the functional core of the rabbit voltage-dependent calcium channel beta2a subunit were expressed in Escherichia coli. These proteins were purified to homogeneity and screened for crystallization. Crystallization conditions were refined using the hanging-drop vapour-diffusion method and two crystal forms were pursued. Crystal form I is represented by thick rods with tetragonal symmetry, unit-cell parameters a = b = 75, c = 165 A and a diffraction limit of 3.4 A which were obtained using ammonium sulfate as a precipitant. Crystal form II gives rise to plates with orthorhombic symmetry, unit-cell parameters a = 35, b = 75, c = 165 A and a diffraction limit of 2.3 A which were grown using polyethylene glycol 20K as a precipitant.
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Affiliation(s)
- Yarden Opatowsky
- Department of Biochemistry, Faculty of Life Sciences, Tel Aviv University, Ramat Aviv 69978, Israel
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Opatowsky Y, Chen CC, Campbell KP, Hirsch JA. Structural Analysis of the Voltage-Dependent Calcium Channel β Subunit Functional Core and Its Complex with the α1 Interaction Domain. Neuron 2004; 42:387-99. [PMID: 15134636 DOI: 10.1016/s0896-6273(04)00250-8] [Citation(s) in RCA: 216] [Impact Index Per Article: 10.8] [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: 02/08/2004] [Revised: 03/23/2004] [Accepted: 04/12/2004] [Indexed: 11/21/2022]
Abstract
Voltage-dependent calcium channels (VDCC) are multiprotein assemblies that regulate the entry of extracellular calcium into electrically excitable cells and serve as signal transduction centers. The alpha1 subunit forms the membrane pore while the intracellular beta subunit is responsible for trafficking of the channel to the plasma membrane and modulation of its electrophysiological properties. Crystallographic analyses of a beta subunit functional core alone and in complex with a alpha1 interaction domain (AID) peptide, the primary binding site of beta to the alpha1 subunit, reveal that beta represents a novel member of the MAGUK protein family. The findings illustrate how the guanylate kinase fold has been fashioned into a protein-protein interaction module by alteration of one of its substrate sites. Combined results indicate that the AID peptide undergoes a helical transition in binding to beta. We outline the mechanistic implications for understanding the beta subunit's broad regulatory role of the VDCC, particularly via the AID.
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Affiliation(s)
- Yarden Opatowsky
- Department of Biochemistry, Faculty of Life Sciences, Tel Aviv University, Ramat Aviv 69978, Israel
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Opatowsky Y, Chomsky-Hecht O, Kang MG, Campbell KP, Hirsch JA. The voltage-dependent calcium channel beta subunit contains two stable interacting domains. J Biol Chem 2003; 278:52323-32. [PMID: 14559910 DOI: 10.1074/jbc.m303564200] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.3] [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
Voltage-dependent calcium channels selectively enable Ca2+ ion movement through cellular membranes. These multiprotein complexes are involved in a wide spectrum of biological processes such as signal transduction and cellular homeostasis. alpha1 is the membrane pore-forming subunit, whereas beta is an intracellular subunit that binds to alpha1, facilitating and modulating channel function. We have expressed, purified, and characterized recombinant beta3 and beta2a using both biochemical and biophysical methods, including electrophysiology, to better understand the beta family's protein structural and functional correlates. Our results indicate that the beta protein is composed of two distinct domains that associate with one another in a stable manner. The data also suggest that the polypeptide regions outside these domains are not structured when beta is not in complex with the channel. In addition, the beta structural core, comprised of just these two domains without other sequences, binds tightly to the alpha interaction domain (AID) motif, a sequence derived from the alpha1 subunit and the principal anchor site of beta. Domain II is responsible for this binding, but domain I enhances it.
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Affiliation(s)
- Yarden Opatowsky
- Department of Biochemistry, Faculty of Life Sciences, Tel Aviv University, Sherman Bldg., Rm. 621, Ramat Aviv 69978, Israel
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