1
|
Todd BP, Downard KM. Structural Phylogenetics with Protein Mass Spectrometry: A Proof-of-Concept. Protein J 2024:10.1007/s10930-024-10227-8. [PMID: 39078529 DOI: 10.1007/s10930-024-10227-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/18/2024] [Indexed: 07/31/2024]
Abstract
It is demonstrated, for the first time, that a mass spectrometry approach (known as phylonumerics) can be successfully implemented for structural phylogenetics investigations to chart the evolution of a protein's structure and function. Illustrated for the compact globular protein myoglobin, peptide masses produced from the proteolytic digestion of the protein across animal species generate trees congruent to the sequence tree counterparts. Single point mutations calculated during the same mass tree building step can be followed along interconnected branches of the tree and represent a viable structural metric. A mass tree built for 15 diverse animal species, easily resolve the birds from mammal species, and the ruminant mammals from the remainder of the animals. Mutations within helix-spanning peptide segments alter both the mass and structure of the protein in these segments. Greater evolution is found in the B-helix over the A, E, F, G and H helices. A further mass tree study, of six more closely related primate species, resolves gorilla from the other primates based on a P22S mutation within the B-helix. The remaining five primates are resolved into two groups based on whether they contain a glycine or serine at position 23 in the same helix. The orangutan is resolved from the gibbon and siamang by its G-helix C110S mutation, while homo sapiens are resolved from chimpanzee based on the Q116H mutation. All are associated with structural perturbations in such helices. These structure altering mutations can be tracked along interconnecting branches of a mass tree, to follow the protein's structure and evolution, and ultimately the evolution of the species in which the proteins are expressed. Those that have the greatest impact on a protein's structure, its function, and ultimately the evolution of the species, can be selectively tracked or monitored.
Collapse
Affiliation(s)
- Benjamin P Todd
- Infectious Disease Responses Laboratory, Prince of Wales Clinical Research Sciences, Sydney, NSW, Australia
| | - Kevin M Downard
- Infectious Disease Responses Laboratory, Prince of Wales Clinical Research Sciences, Sydney, NSW, Australia.
| |
Collapse
|
2
|
Loffredo M, Casciaro B, Bellavita R, Troiano C, Brancaccio D, Cappiello F, Merlino F, Galdiero S, Fabrizi G, Grieco P, Stella L, Carotenuto A, Mangoni ML. Strategic Single-Residue Substitution in the Antimicrobial Peptide Esc(1-21) Confers Activity against Staphylococcus aureus, Including Drug-Resistant and Biofilm Phenotype. ACS Infect Dis 2024; 10:2403-2418. [PMID: 38848266 PMCID: PMC11250030 DOI: 10.1021/acsinfecdis.4c00130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Revised: 05/21/2024] [Accepted: 05/22/2024] [Indexed: 06/09/2024]
Abstract
Staphylococcus aureus, a bacterium resistant to multiple drugs, is a significant cause of illness and death worldwide. Antimicrobial peptides (AMPs) provide an excellent potential strategy to cope with this threat. Recently, we characterized a derivative of the frog-skin AMP esculentin-1a, Esc(1-21) (1) that is endowed with potent activity against Gram-negative bacteria but poor efficacy against Gram-positive strains. In this study, three analogues of peptide 1 were designed by replacing Gly8 with α-aminoisobutyric acid (Aib), Pro, and dPro (2-4, respectively). The single substitution Gly8 → Aib8 in peptide 2 makes it active against the planktonic form of Gram-positive bacterial strains, especially Staphylococcus aureus, including multidrug-resistant clinical isolates, with an improved biostability without resulting in cytotoxicity to mammalian cells. Moreover, peptide 2 showed a higher antibiofilm activity than peptide 1 against both reference and clinical isolates of S. aureus. Peptide 2 was also able to induce rapid bacterial killing, suggesting a membrane-perturbing mechanism of action. Structural analysis of the most active peptide 2 evidenced that the improved biological activity of peptide 2 is the consequence of a combination of higher biostability, higher α helical content, and ability to reduce membrane fluidity and to adopt a distorted helix, bent in correspondence of Aib8. Overall, this study has shown how a strategic single amino acid substitution is sufficient to enlarge the spectrum of activity of the original peptide 1, and improve its biological properties for therapeutic purposes, thus paving the way to optimize AMPs for the development of new broad-spectrum anti-infective agents.
Collapse
Affiliation(s)
- Maria
Rosa Loffredo
- Department
of Biochemical Sciences, Laboratory Affiliated to Istituto Pasteur
Italia-Fondazione Cenci Bolognetti, Sapienza
University of Rome, 00185 Rome, Italy
| | - Bruno Casciaro
- Department
of Biochemical Sciences, Laboratory Affiliated to Istituto Pasteur
Italia-Fondazione Cenci Bolognetti, Sapienza
University of Rome, 00185 Rome, Italy
| | - Rosa Bellavita
- Department
of Pharmacy, University of Naples “Federico
II”, 80131 Naples, Italy
| | - Cassandra Troiano
- Department
of Chemical Science and Technologies, University
of Rome Tor Vergata, 00133 Rome, Italy
| | - Diego Brancaccio
- Department
of Pharmacy, University of Naples “Federico
II”, 80131 Naples, Italy
| | - Floriana Cappiello
- Department
of Biochemical Sciences, Laboratory Affiliated to Istituto Pasteur
Italia-Fondazione Cenci Bolognetti, Sapienza
University of Rome, 00185 Rome, Italy
| | - Francesco Merlino
- Department
of Pharmacy, University of Naples “Federico
II”, 80131 Naples, Italy
| | - Stefania Galdiero
- Department
of Pharmacy, University of Naples “Federico
II”, 80131 Naples, Italy
| | - Giancarlo Fabrizi
- Department
of Chemistry and Technology of Drugs, “Department of Excellence
2018−2022”, Sapienza University
of Rome, 00185 Rome, Italy
| | - Paolo Grieco
- Department
of Pharmacy, University of Naples “Federico
II”, 80131 Naples, Italy
| | - Lorenzo Stella
- Department
of Chemical Science and Technologies, University
of Rome Tor Vergata, 00133 Rome, Italy
| | - Alfonso Carotenuto
- Department
of Pharmacy, University of Naples “Federico
II”, 80131 Naples, Italy
| | - Maria Luisa Mangoni
- Department
of Biochemical Sciences, Laboratory Affiliated to Istituto Pasteur
Italia-Fondazione Cenci Bolognetti, Sapienza
University of Rome, 00185 Rome, Italy
| |
Collapse
|
3
|
Yee SW, Ferrández-Peral L, Alentorn-Moron P, Fontsere C, Ceylan M, Koleske ML, Handin N, Artegoitia VM, Lara G, Chien HC, Zhou X, Dainat J, Zalevsky A, Sali A, Brand CM, Wolfreys FD, Yang J, Gestwicki JE, Capra JA, Artursson P, Newman JW, Marquès-Bonet T, Giacomini KM. Illuminating the function of the orphan transporter, SLC22A10, in humans and other primates. Nat Commun 2024; 15:4380. [PMID: 38782905 PMCID: PMC11116522 DOI: 10.1038/s41467-024-48569-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 05/06/2024] [Indexed: 05/25/2024] Open
Abstract
SLC22A10 is an orphan transporter with unknown substrates and function. The goal of this study is to elucidate its substrate specificity and functional characteristics. In contrast to orthologs from great apes, human SLC22A10, tagged with green fluorescent protein, is not expressed on the plasma membrane. Cells expressing great ape SLC22A10 orthologs exhibit significant accumulation of estradiol-17β-glucuronide, unlike those expressing human SLC22A10. Sequence alignments reveal a proline at position 220 in humans, which is a leucine in great apes. Replacing proline with leucine in SLC22A10-P220L restores plasma membrane localization and uptake function. Neanderthal and Denisovan genomes show proline at position 220, akin to modern humans, indicating functional loss during hominin evolution. Human SLC22A10 is a unitary pseudogene due to a fixed missense mutation, P220, while in great apes, its orthologs transport sex steroid conjugates. Characterizing SLC22A10 across species sheds light on its biological role, influencing organism development and steroid homeostasis.
Collapse
Affiliation(s)
- Sook Wah Yee
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA, USA
| | - Luis Ferrández-Peral
- Institute of Evolutionary Biology (UPF-CSIC), PRBB, Dr. Aiguader 88, 08003, Barcelona, Spain
| | - Pol Alentorn-Moron
- Institute of Evolutionary Biology (UPF-CSIC), PRBB, Dr. Aiguader 88, 08003, Barcelona, Spain
| | - Claudia Fontsere
- Institute of Evolutionary Biology (UPF-CSIC), PRBB, Dr. Aiguader 88, 08003, Barcelona, Spain
- Center for Evolutionary Hologenomics, The Globe Institute, University of Copenhagen, Øster Farimagsgade 5A, 1352, Copenhagen, Denmark
| | - Merve Ceylan
- Department of Pharmacy, Uppsala University, Uppsala, Sweden
| | - Megan L Koleske
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA, USA
| | - Niklas Handin
- Department of Pharmacy, Uppsala University, Uppsala, Sweden
| | - Virginia M Artegoitia
- United States Department of Agriculture, Agricultural Research Service, Western Human Nutrition Research Center, Davis, CA, 95616, USA
| | - Giovanni Lara
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA, USA
| | - Huan-Chieh Chien
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA, USA
| | - Xujia Zhou
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA, USA
| | - Jacques Dainat
- Joint Research Unit for Infectious Diseases and Vectors Ecology Genetics Evolution and Control (MIVEGEC), University of Montpellier, French National Center for Scientific Research (CNRS 5290), French National Research Institute for Sustainable Development (IRD 224), 911 Avenue Agropolis, BP 64501, 34394, Montpellier Cedex 5, France
| | - Arthur Zalevsky
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA, USA
| | - Andrej Sali
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA, USA
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA
- Quantitative Biosciences Institute (QBI), University of California, San Francisco, San Francisco, CA, US
| | - Colin M Brand
- Bakar Computational Health Sciences Institute, University of California, San Francisco, CA, USA
- Department of Epidemiology and Biostatistics, University of California, San Francisco, CA, USA
| | - Finn D Wolfreys
- Department of Ophthalmology, University of California, San Francisco, CA, USA
| | - Jia Yang
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA, USA
| | - Jason E Gestwicki
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, USA
- Institute for Neurodegenerative Diseases, University of California, San Francisco, CA, USA
| | - John A Capra
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA, USA
- Bakar Computational Health Sciences Institute, University of California, San Francisco, CA, USA
- Department of Epidemiology and Biostatistics, University of California, San Francisco, CA, USA
- Institute for Human Genetics, University of California San Francisco, San Francisco, CA, USA
| | - Per Artursson
- Department of Pharmacy, Uppsala University, Uppsala, Sweden
- Science for Life Laboratories, Uppsala University, Uppsala, Sweden
| | - John W Newman
- United States Department of Agriculture, Agricultural Research Service, Western Human Nutrition Research Center, Davis, CA, 95616, USA
- Department of Nutrition, University of California, Davis, Davis, CA, 95616, USA
| | - Tomàs Marquès-Bonet
- Institute of Evolutionary Biology (UPF-CSIC), PRBB, Dr. Aiguader 88, 08003, Barcelona, Spain
- Catalan Institution of Research and Advanced Studies (ICREA), Passeig de Lluís Companys, 23, 08010, Barcelona, Spain
- CNAG, Centro Nacional de Analisis Genomico, Barcelona Institute of Science and Technology (BIST), Baldiri i Reixac 4, 08028, Barcelona, Spain
- Institut Català de Paleontologia Miquel Crusafont, Universitat Autònoma de Barcelona, Edifici ICTA-ICP, c/ Columnes s/n, 08193, Cerdanyola del Vallès, Barcelona, Spain
| | - Kathleen M Giacomini
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, CA, USA.
- Institute for Human Genetics, University of California San Francisco, San Francisco, CA, USA.
| |
Collapse
|
4
|
Li W, Jacobsen MT, Park C, Jung JU, Lin NP, Huang PS, Lal RA, Chou DHC. A cysteine-specific solubilizing tag strategy enables efficient chemical protein synthesis of difficult targets. Chem Sci 2024; 15:3214-3222. [PMID: 38425513 PMCID: PMC10901488 DOI: 10.1039/d3sc06032b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 01/18/2024] [Indexed: 03/02/2024] Open
Abstract
We developed a new cysteine-specific solubilizing tag strategy via a cysteine-conjugated succinimide. This solubilizing tag remains stable under common native chemical ligation conditions and can be efficiently removed with palladium-based catalysts. Utilizing this approach, we synthesized two proteins containing notably difficult peptide segments: interleukin-2 (IL-2) and insulin. This IL-2 chemical synthesis represents the simplest and most efficient approach to date, which is enabled by the cysteine-specific solubilizing tag to synthesize and ligate long peptide segments. Additionally, we synthesized a T8P insulin variant, previously identified in an infant with neonatal diabetes. We show that T8P insulin exhibits reduced bioactivity (a 30-fold decrease compared to standard insulin), potentially contributing to the onset of diabetes in these patients. In summary, our work provides an efficient tool to synthesize challenging proteins and opens new avenues for exploring research directions in understanding their biological functions.
Collapse
Affiliation(s)
- Wenchao Li
- División of Endocrinology and Diabetes, Department of Pediatrics, School of Medicine, Stanford University Palo Alto CA 94305 USA
| | - Michael T Jacobsen
- División of Endocrinology and Diabetes, Department of Pediatrics, School of Medicine, Stanford University Palo Alto CA 94305 USA
| | - Claire Park
- División of Endocrinology and Diabetes, Department of Pediatrics, School of Medicine, Stanford University Palo Alto CA 94305 USA
| | - Jae Un Jung
- División of Endocrinology and Diabetes, Department of Pediatrics, School of Medicine, Stanford University Palo Alto CA 94305 USA
| | - Nai-Pin Lin
- División of Endocrinology and Diabetes, Department of Pediatrics, School of Medicine, Stanford University Palo Alto CA 94305 USA
| | - Po-Ssu Huang
- Department of Bioengineering, Stanford University Palo Alto CA 94305 USA
| | - Rayhan A Lal
- Division of Endocrinology, Department of Medicine, School of Medicine, Stanford University Palo Alto CA 94305 USA
| | - Danny Hung-Chieh Chou
- División of Endocrinology and Diabetes, Department of Pediatrics, School of Medicine, Stanford University Palo Alto CA 94305 USA
| |
Collapse
|
5
|
Peterson BG, Hwang J, Russ JE, Schroeder JW, Freddolino PL, Baldridge RD. Deep mutational scanning highlights a role for cytosolic regions in Hrd1 function. Cell Rep 2023; 42:113451. [PMID: 37980570 PMCID: PMC10751623 DOI: 10.1016/j.celrep.2023.113451] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 10/10/2023] [Accepted: 11/01/2023] [Indexed: 11/21/2023] Open
Abstract
Misfolded endoplasmic reticulum (ER) proteins are degraded through a process called ER-associated degradation (ERAD). Soluble, lumenal ERAD targets are recognized, retrotranslocated across the ER membrane, ubiquitinated, extracted from the membrane, and degraded by the proteasome using an ERAD pathway containing a ubiquitin ligase called Hrd1. To determine how Hrd1 mediates these processes, we developed a deep mutational scanning approach to identify residues involved in Hrd1 function, including those exclusively required for lumenal degradation. We identify several regions required for different Hrd1 functions. Most surprisingly, we find two cytosolic regions of Hrd1 required for lumenal ERAD substrate degradation. Using in vivo and in vitro approaches, we define roles for disordered regions between structural elements that are required for Hrd1 autoubiquitination and substrate interaction. Our results demonstrate that disordered cytosolic regions promote substrate retrotranslocation by controlling Hrd1 activation and establishing directionality of retrotranslocation for lumenal substrate across the ER membrane.
Collapse
Affiliation(s)
- Brian G Peterson
- Department of Biological Chemistry, University of Michigan Medical School, 1150 W Medical Center Drive, Ann Arbor, MI 48109, USA
| | - Jiwon Hwang
- Department of Biological Chemistry, University of Michigan Medical School, 1150 W Medical Center Drive, Ann Arbor, MI 48109, USA
| | - Jennifer E Russ
- Department of Biological Chemistry, University of Michigan Medical School, 1150 W Medical Center Drive, Ann Arbor, MI 48109, USA
| | - Jeremy W Schroeder
- Department of Biological Chemistry, University of Michigan Medical School, 1150 W Medical Center Drive, Ann Arbor, MI 48109, USA
| | - P Lydia Freddolino
- Department of Biological Chemistry, University of Michigan Medical School, 1150 W Medical Center Drive, Ann Arbor, MI 48109, USA; Cellular and Molecular Biology Program, University of Michigan Medical School, 1150 W Medical Center Drive, Ann Arbor, MI 48109, USA; Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Ryan D Baldridge
- Department of Biological Chemistry, University of Michigan Medical School, 1150 W Medical Center Drive, Ann Arbor, MI 48109, USA; Cellular and Molecular Biology Program, University of Michigan Medical School, 1150 W Medical Center Drive, Ann Arbor, MI 48109, USA.
| |
Collapse
|
6
|
Ortner M, Guschtschin-Schmidt N, Stelzer W, Muhle-Goll C, Langosch D. Permissive Conformations of a Transmembrane Helix Allow Intramembrane Proteolysis by γ-Secretase. J Mol Biol 2023; 435:168218. [PMID: 37536392 DOI: 10.1016/j.jmb.2023.168218] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 07/26/2023] [Accepted: 07/26/2023] [Indexed: 08/05/2023]
Abstract
The intramembrane protease γ-secretase activates important signaling molecules, such as Notch receptors. It is still unclear, however, how different elements within the primary structure of substrate transmembrane domains (TMDs) contribute to their cleavability. Using a newly developed yeast-based cleavage assay, we identified three crucial regions within the TMDs of the paralogs Notch1 and Notch3 by mutational and gain-of-function approaches. The AAAA or AGAV motifs within the N-terminal half of the TMDs were found to confer strong conformational flexibility to these TMD helices, as determined by mutagenesis coupled to deuterium/hydrogen exchange. Crucial amino acids within the C-terminal half may support substrate docking into the catalytic cleft of presenilin, the enzymatic subunit of γ-secretase. Further, residues close to the C-termini of the TMDs may stabilize a tripartite β-sheet in the substrate/enzyme complex. NMR structures reveal different extents of helix bending as well as an ability to adopt widely differing conformational substates, depending on the sequence of the N-terminal half. The difference in cleavability between Notch1 and Notch3 TMDs is jointly determined by the conformational repertoires of the TMD helices and the sequences of the C-terminal half, as suggested by mutagenesis and building molecular models. In sum, cleavability of a γ-secretase substrate is enabled by different functions of cooperating TMD regions, which deepens our mechanistic understanding of substrate/non-substrate discrimination in intramembrane proteolysis.
Collapse
Affiliation(s)
- Martin Ortner
- Chair of Biopolymer Chemistry, Technical University of Munich, Freising, Germany
| | - Nadja Guschtschin-Schmidt
- Institute for Biological Interfaces 4, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany; Institute of Organic Chemistry, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Walter Stelzer
- Chair of Biopolymer Chemistry, Technical University of Munich, Freising, Germany
| | - Claudia Muhle-Goll
- Institute for Biological Interfaces 4, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany; Institute of Organic Chemistry, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Dieter Langosch
- Chair of Biopolymer Chemistry, Technical University of Munich, Freising, Germany.
| |
Collapse
|
7
|
Yee SW, Ferrández-Peral L, Alentorn P, Fontsere C, Ceylan M, Koleske ML, Handin N, Artegoitia VM, Lara G, Chien HC, Zhou X, Dainat J, Zalevsky A, Sali A, Brand CM, Capra JA, Artursson P, Newman JW, Marques-Bonet T, Giacomini KM. Illuminating the Function of the Orphan Transporter, SLC22A10 in Humans and Other Primates. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.08.552553. [PMID: 37609337 PMCID: PMC10441401 DOI: 10.1101/2023.08.08.552553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
SLC22A10 is classified as an orphan transporter with unknown substrates and function. Here we describe the discovery of the substrate specificity and functional characteristics of SLC22A10. The human SLC22A10 tagged with green fluorescent protein was found to be absent from the plasma membrane, in contrast to the SLC22A10 orthologs found in great apes. Estradiol-17β-glucuronide accumulated in cells expressing great ape SLC22A10 orthologs (over 4-fold, p<0.001). In contrast, human SLC22A10 displayed no uptake function. Sequence alignments revealed two amino acid differences including a proline at position 220 of the human SLC22A10 and a leucine at the same position of great ape orthologs. Site-directed mutagenesis yielding the human SLC22A10-P220L produced a protein with excellent plasma membrane localization and associated uptake function. Neanderthal and Denisovan genomes show human-like sequences at proline 220 position, corroborating that SLC22A10 were rendered nonfunctional during hominin evolution after the divergence from the pan lineage (chimpanzees and bonobos). These findings demonstrate that human SLC22A10 is a unitary pseudogene and was inactivated by a missense mutation that is fixed in humans, whereas orthologs in great apes transport sex steroid conjugates.
Collapse
Affiliation(s)
- Sook Wah Yee
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, California, USA
| | | | - Pol Alentorn
- Institute of Evolutionary Biology (UPF-CSIC), PRBB, 08003 Barcelona, Spain
| | - Claudia Fontsere
- Institute of Evolutionary Biology (UPF-CSIC), PRBB, 08003 Barcelona, Spain; Center for Evolutionary Hologenomics, The Globe Institute, University of Copenhagen, Øster Farimagsgade 5A, 1352 Copenhagen, Denmark
| | - Merve Ceylan
- Department of Pharmacy and Science for Life Laboratory, Uppsala University, P.O. Box 580, 75123, Uppsala, Sweden
| | - Megan L. Koleske
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, California, USA
| | - Niklas Handin
- Department of Pharmacy and Science for Life Laboratory, Uppsala University, P.O. Box 580, 75123, Uppsala, Sweden
| | - Virginia M. Artegoitia
- United States Department of Agriculture, Agricultural Research Service, Western Human Nutrition Research Center, Davis, CA 95616, USA
| | - Giovanni Lara
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, California, USA
| | - Huan-Chieh Chien
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, California, USA
| | - Xujia Zhou
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, California, USA
| | - Jacques Dainat
- Joint Research Unit for Infectious Diseases and Vectors Ecology Genetics Evolution and Control (MIVEGEC), University of Montpellier, French National Center for Scientific Research (CNRS 5290), French National Research Institute for Sustainable Development (IRD 224), 911 Avenue Agropolis, BP 64501, 34394 Montpellier Cedex 5, France
| | - Arthur Zalevsky
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, California, USA
| | - Andrej Sali
- Department of Bioengineering and Therapeutic Sciences, UCSF Box 0775 1700 4th St, University of California, San Francisco, San Francisco, CA 94158, United States; Department of Pharmaceutical Chemistry, University of California, San Francisco, UCSF Box 2880 600 16th St, San Francisco, CA 94143, United States; Quantitative Biosciences Institute (QBI), University of California, San Francisco, 1700 4th St, San Francisco, CA, United States
| | - Colin M. Brand
- Bakar Computational Health Sciences Institute, University of California, San Francisco, CA, USA; Department of Epidemiology and Biostatistics, University of California, San Francisco, CA, USA
| | - John A. Capra
- Bakar Computational Health Sciences Institute, University of California, San Francisco, CA, USA; Department of Epidemiology and Biostatistics, University of California, San Francisco, CA, USA
| | - Per Artursson
- Department of Pharmacy and Science for Life Laboratory, Uppsala University, P.O. Box 580, 75123, Uppsala, Sweden
| | - John W. Newman
- United States Department of Agriculture, Agricultural Research Service, Western Human Nutrition Research Center, Davis, CA 95616, USA; Department of Nutrition, University of California, Davis, Davis, CA 95616, USA; UC Davis West Coast Metabolomics Center, Davis, CA 95616, USA
| | - Tomas Marques-Bonet
- Institute of Evolutionary Biology (UPF-CSIC), PRBB, 08003 Barcelona, Spain; Institute of Evolutionary Biology (UPF-CSIC), PRBB, Dr. Aiguader 88, 08003 Barcelona, Spain; Catalan Institution of Research and Advanced Studies (ICREA), Passeig de Lluís Companys, 23, 08010, Barcelona, Spain; CNAG, Centro Nacional de Analisis Genomico, Barcelona Institute of Science and Technology (BIST), Baldiri i Reixac 4, 08028 Barcelona, Spain; Institut Català de Paleontologia Miquel Crusafont, Universitat Autònoma de Barcelona, Edifici ICTA-ICP, c/ Columnes s/n, 08193 Cerdanyola del Vallès, Barcelona, Spain
| | - Kathleen M. Giacomini
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, California, USA
- Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco, California, USA; Institute for Human Genetics, University of California San Francisco, San Francisco, CA, USA
| |
Collapse
|
8
|
Stewart A, Dershwitz P, Stewart C, Sawaya MR, Yeates TO, Semrau JD, Zischka H, DiSpirito AA, Bobik TA. Crystal structure of MbnF: an NADPH-dependent flavin monooxygenase from Methylocystis strain SB2. Acta Crystallogr F Struct Biol Commun 2023; 79:111-118. [PMID: 37158309 PMCID: PMC10167746 DOI: 10.1107/s2053230x23003035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 04/02/2023] [Indexed: 05/10/2023] Open
Abstract
Methanobactins (MBs) are ribosomally produced and post-translationally modified peptides (RiPPs) that are used by methanotrophs for copper acquisition. The signature post-translational modification of MBs is the formation of two heterocyclic groups, either an oxazolone, pyrazinedione or imidazolone group, with an associated thioamide from an X-Cys dipeptide. The precursor peptide (MbnA) for MB formation is found in a gene cluster of MB-associated genes. The exact biosynthetic pathway of MB formation is not yet fully understood, and there are still uncharacterized proteins in some MB gene clusters, particularly those that produce pyrazinedione or imidazolone rings. One such protein is MbnF, which is proposed to be a flavin monooxygenase (FMO) based on homology. To help to elucidate its possible function, MbnF from Methylocystis sp. strain SB2 was recombinantly produced in Escherichia coli and its X-ray crystal structure was resolved to 2.6 Å resolution. Based on its structural features, MbnF appears to be a type A FMO, most of which catalyze hydroxylation reactions. Preliminary functional characterization shows that MbnF preferentially oxidizes NADPH over NADH, supporting NAD(P)H-mediated flavin reduction, which is the initial step in the reaction cycle of several type A FMO enzymes. It is also shown that MbnF binds the precursor peptide for MB, with subsequent loss of the leader peptide sequence as well as the last three C-terminal amino acids, suggesting that MbnF might be needed for this process to occur. Finally, molecular-dynamics simulations revealed a channel in MbnF that is capable of accommodating the core MbnA fragment minus the three C-terminal amino acids.
Collapse
Affiliation(s)
- Andrew Stewart
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA 50011-3260, USA
| | - Philip Dershwitz
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA 50011-3260, USA
| | - Charles Stewart
- Macromolecular X-ray Crystallography Facility, Office of Biotechnology, Iowa State University, Ames, IA 50011-3260, USA
| | - Michael R Sawaya
- UCLA-DOE Institute for Genomics and Proteomics, University of California Los Angeles, Los Angeles, CA 90095-1570, USA
| | - Todd O Yeates
- UCLA-DOE Institute for Genomics and Proteomics, University of California Los Angeles, Los Angeles, CA 90095-1570, USA
| | - Jeremy D Semrau
- Department of Civil and Environmental Engineering, University of Michigan, Ann Arbor, MI 48109-2125, USA
| | - Hans Zischka
- Institute of Molecular Toxicology and Pharmacology, Helmholtz Center Munich, German Research Center for Environmental Health, Ingolstaedter Landstrasse 1, 85764 Neuherberg, Germany
| | - Alan A DiSpirito
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA 50011-3260, USA
| | - Thomas A Bobik
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA 50011-3260, USA
| |
Collapse
|
9
|
Peterson BG, Hwang J, Russ JE, Schroeder J, Freddolino PL, Baldridge RD. Deep mutational scanning highlights a new role for cytosolic regions in Hrd1 function. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.03.535444. [PMID: 37066402 PMCID: PMC10103981 DOI: 10.1101/2023.04.03.535444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Misfolded endoplasmic reticulum proteins are degraded through a process called endoplasmic reticulum associated degradation (ERAD). Soluble, lumenal ERAD targets are recognized, retrotranslocated across the ER membrane, ubiquitinated, extracted from the membrane, and degraded by the proteasome using an ERAD pathway containing a ubiquitin ligase called Hrd1. To determine how Hrd1 mediates these processes, we developed a deep mutational scanning approach to identify residues involved in Hrd1 function, including those exclusively required for lumenal degradation. We identified several regions required for different Hrd1 functions. Most surprisingly, we found two cytosolic regions of Hrd1 required for lumenal ERAD substrate degradation. Using in vivo and in vitro approaches, we defined roles for disordered regions between structural elements that were required for Hrd1's ability to autoubiquitinate and interact with substrate. Our results demonstrate that disordered cytosolic regions promote substrate retrotranslocation by controlling Hrd1 activation and establishing directionality of retrotranslocation for lumenal substrate across the endoplasmic reticulum membrane.
Collapse
Affiliation(s)
- Brian G. Peterson
- Department of Biological Chemistry, University of Michigan Medical School, 1150 W Medical Center Drive, Ann Arbor, MI 48109, USA
| | - Jiwon Hwang
- Department of Biological Chemistry, University of Michigan Medical School, 1150 W Medical Center Drive, Ann Arbor, MI 48109, USA
| | - Jennifer E. Russ
- Department of Biological Chemistry, University of Michigan Medical School, 1150 W Medical Center Drive, Ann Arbor, MI 48109, USA
| | - Jeremy Schroeder
- Department of Biological Chemistry, University of Michigan Medical School, 1150 W Medical Center Drive, Ann Arbor, MI 48109, USA
| | - Peter L. Freddolino
- Department of Biological Chemistry, University of Michigan Medical School, 1150 W Medical Center Drive, Ann Arbor, MI 48109, USA
- Cellular and Molecular Biology Program, University of Michigan Medical School, 1150 W Medical Center Drive, Ann Arbor, MI 48109, USA
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School
| | - Ryan D. Baldridge
- Department of Biological Chemistry, University of Michigan Medical School, 1150 W Medical Center Drive, Ann Arbor, MI 48109, USA
- Cellular and Molecular Biology Program, University of Michigan Medical School, 1150 W Medical Center Drive, Ann Arbor, MI 48109, USA
| |
Collapse
|
10
|
Specific Mutations near the Amyloid Precursor Protein Cleavage Site Increase γ-Secretase Sensitivity and Modulate Amyloid-β Production. Int J Mol Sci 2023; 24:ijms24043970. [PMID: 36835396 PMCID: PMC9959964 DOI: 10.3390/ijms24043970] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 01/16/2023] [Accepted: 02/13/2023] [Indexed: 02/18/2023] Open
Abstract
Amyloid-β peptides (Aβs) are produced via cleavage of the transmembrane region of the amyloid precursor protein (APP) by γ-secretase and are responsible for Alzheimer's disease. Familial Alzheimer's disease (FAD) is associated with APP mutations that disrupt the cleavage reaction and increase the production of neurotoxic Aβs, i.e., Aβ42 and Aβ43. Study of the mutations that activate and restore the cleavage of FAD mutants is necessary to understand the mechanism of Aβ production. In this study, using a yeast reconstruction system, we revealed that one of the APP FAD mutations, T714I, severely reduced the cleavage, and identified secondary APP mutations that restored the cleavage of APP T714I. Some mutants were able to modulate Aβ production by changing the proportions of Aβ species when introduced into mammalian cells. Secondary mutations include proline and aspartate residues; proline mutations are thought to act through helical structural destabilization, while aspartate mutations are thought to promote interactions in the substrate binding pocket. Our results elucidate the APP cleavage mechanism and could facilitate drug discovery.
Collapse
|
11
|
Papadopoulou AA, Stelzer W, Silber M, Schlosser C, Spitz C, Haug-Kröper M, Straub T, Müller SA, Lichtenthaler SF, Muhle-Goll C, Langosch D, Fluhrer R. Helical stability of the GnTV transmembrane domain impacts on SPPL3 dependent cleavage. Sci Rep 2022; 12:20987. [PMID: 36470941 PMCID: PMC9722940 DOI: 10.1038/s41598-022-24772-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 11/21/2022] [Indexed: 12/12/2022] Open
Abstract
Signal-Peptide Peptidase Like-3 (SPPL3) is an intramembrane cleaving aspartyl protease that causes secretion of extracellular domains from type-II transmembrane proteins. Numerous Golgi-localized glycosidases and glucosyltransferases have been identified as physiological SPPL3 substrates. By SPPL3 dependent processing, glycan-transferring enzymes are deactivated inside the cell, as their active site-containing domain is cleaved and secreted. Thus, SPPL3 impacts on glycan patterns of many cellular and secreted proteins and can regulate protein glycosylation. However, the characteristics that make a substrate a favourable candidate for SPPL3-dependent cleavage remain unknown. To gain insights into substrate requirements, we investigated the function of a GxxxG motif located in the transmembrane domain of N-acetylglucosaminyltransferase V (GnTV), a well-known SPPL3 substrate. SPPL3-dependent secretion of the substrate's ectodomain was affected by mutations disrupting the GxxxG motif. Using deuterium/hydrogen exchange and NMR spectroscopy, we studied the effect of these mutations on the helix flexibility of the GnTV transmembrane domain and observed that increased flexibility facilitates SPPL3-dependent shedding and vice versa. This study provides first insights into the characteristics of SPPL3 substrates, combining molecular biology, biochemistry, and biophysical techniques and its results will provide the basis for better understanding the characteristics of SPPL3 substrates with implications for the substrates of other intramembrane proteases.
Collapse
Affiliation(s)
- Alkmini A. Papadopoulou
- grid.7307.30000 0001 2108 9006Biochemistry and Molecular Biology, Institute of Theoretical Medicine, Faculty of Medicine, University of Augsburg, Universitätstrasse 2, 86159 Augsburg, Germany
| | - Walter Stelzer
- grid.6936.a0000000123222966Lehrstuhl für Chemie der Biopolymere, Technische Universität München, Weihenstephaner Berg 3, 85354 Freising, Germany
| | - Mara Silber
- grid.7892.40000 0001 0075 5874Institute for Biological Interfaces 4, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany ,grid.7892.40000 0001 0075 5874Institute of Organic Chemistry, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Christine Schlosser
- grid.7307.30000 0001 2108 9006Biochemistry and Molecular Biology, Institute of Theoretical Medicine, Faculty of Medicine, University of Augsburg, Universitätstrasse 2, 86159 Augsburg, Germany
| | - Charlotte Spitz
- grid.7307.30000 0001 2108 9006Biochemistry and Molecular Biology, Institute of Theoretical Medicine, Faculty of Medicine, University of Augsburg, Universitätstrasse 2, 86159 Augsburg, Germany
| | - Martina Haug-Kröper
- grid.7307.30000 0001 2108 9006Biochemistry and Molecular Biology, Institute of Theoretical Medicine, Faculty of Medicine, University of Augsburg, Universitätstrasse 2, 86159 Augsburg, Germany
| | - Tobias Straub
- grid.5252.00000 0004 1936 973XCore Facility Bioinformatics, Biomedical Center, Ludwig Maximilians University Munich, 82152 Planegg-Martinsried, Germany
| | - Stephan A. Müller
- grid.424247.30000 0004 0438 0426DZNE – German Center for Neurodegenerative Diseases, Munich, Germany
| | - Stefan F. Lichtenthaler
- grid.424247.30000 0004 0438 0426DZNE – German Center for Neurodegenerative Diseases, Munich, Germany ,grid.15474.330000 0004 0477 2438Neuroproteomics, School of Medicine, Klinikum rechts der Isar, Technical University of Munich, 81675 Munich, Germany ,grid.452617.3Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Claudia Muhle-Goll
- grid.7892.40000 0001 0075 5874Institute for Biological Interfaces 4, Karlsruhe Institute of Technology, 76344 Eggenstein-Leopoldshafen, Germany ,grid.7892.40000 0001 0075 5874Institute of Organic Chemistry, Karlsruhe Institute of Technology, 76131 Karlsruhe, Germany
| | - Dieter Langosch
- grid.6936.a0000000123222966Lehrstuhl für Chemie der Biopolymere, Technische Universität München, Weihenstephaner Berg 3, 85354 Freising, Germany
| | - Regina Fluhrer
- grid.7307.30000 0001 2108 9006Biochemistry and Molecular Biology, Institute of Theoretical Medicine, Faculty of Medicine, University of Augsburg, Universitätstrasse 2, 86159 Augsburg, Germany
| |
Collapse
|
12
|
Bloemeke N, Meighen‐Berger K, Hitzenberger M, Bach NC, Parr M, Coelho JPL, Frishman D, Zacharias M, Sieber SA, Feige MJ. Intramembrane client recognition potentiates the chaperone functions of calnexin. EMBO J 2022; 41:e110959. [PMID: 36314723 PMCID: PMC9753464 DOI: 10.15252/embj.2022110959] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 10/11/2022] [Accepted: 10/13/2022] [Indexed: 11/06/2022] Open
Abstract
One-third of the human proteome is comprised of membrane proteins, which are particularly vulnerable to misfolding and often require folding assistance by molecular chaperones. Calnexin (CNX), which engages client proteins via its sugar-binding lectin domain, is one of the most abundant ER chaperones, and plays an important role in membrane protein biogenesis. Based on mass spectrometric analyses, we here show that calnexin interacts with a large number of nonglycosylated membrane proteins, indicative of additional nonlectin binding modes. We find that calnexin preferentially bind misfolded membrane proteins and that it uses its single transmembrane domain (TMD) for client recognition. Combining experimental and computational approaches, we systematically dissect signatures for intramembrane client recognition by calnexin, and identify sequence motifs within the calnexin TMD region that mediate client binding. Building on this, we show that intramembrane client binding potentiates the chaperone functions of calnexin. Together, these data reveal a widespread role of calnexin client recognition in the lipid bilayer, which synergizes with its established lectin-based substrate binding. Molecular chaperones thus can combine different interaction modes to support the biogenesis of the diverse eukaryotic membrane proteome.
Collapse
Affiliation(s)
- Nicolas Bloemeke
- Department of Bioscience, Center for Functional Protein Assemblies (CPA), TUM School of Natural SciencesTechnical University of MunichGarchingGermany
| | - Kevin Meighen‐Berger
- Department of Bioscience, Center for Functional Protein Assemblies (CPA), TUM School of Natural SciencesTechnical University of MunichGarchingGermany
| | - Manuel Hitzenberger
- Department of Bioscience, Center for Functional Protein Assemblies (CPA), TUM School of Natural SciencesTechnical University of MunichGarchingGermany
| | - Nina C Bach
- Department of Bioscience, Center for Functional Protein Assemblies (CPA), TUM School of Natural SciencesTechnical University of MunichGarchingGermany
| | - Marina Parr
- Department of Bioinformatics, TUM School of Life SciencesTechnical University of MunichFreisingGermany
| | - Joao PL Coelho
- Department of Bioscience, Center for Functional Protein Assemblies (CPA), TUM School of Natural SciencesTechnical University of MunichGarchingGermany
| | - Dmitrij Frishman
- Department of Bioinformatics, TUM School of Life SciencesTechnical University of MunichFreisingGermany
| | - Martin Zacharias
- Department of Bioscience, Center for Functional Protein Assemblies (CPA), TUM School of Natural SciencesTechnical University of MunichGarchingGermany
| | - Stephan A Sieber
- Department of Bioscience, Center for Functional Protein Assemblies (CPA), TUM School of Natural SciencesTechnical University of MunichGarchingGermany
| | - Matthias J Feige
- Department of Bioscience, Center for Functional Protein Assemblies (CPA), TUM School of Natural SciencesTechnical University of MunichGarchingGermany
| |
Collapse
|
13
|
Azzaz F, Yahi N, Chahinian H, Fantini J. The Epigenetic Dimension of Protein Structure Is an Intrinsic Weakness of the AlphaFold Program. Biomolecules 2022; 12:biom12101527. [PMID: 36291736 PMCID: PMC9599222 DOI: 10.3390/biom12101527] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Revised: 10/12/2022] [Accepted: 10/16/2022] [Indexed: 12/02/2022] Open
Abstract
One of the most important lessons we have learned from sequencing the human genome is that not all proteins have a 3D structure. In fact, a large part of the human proteome is made up of intrinsically disordered proteins (IDPs) which can adopt multiple structures, and therefore, multiple functions, depending on the ligands with which they interact. Under these conditions, one can wonder about the value of algorithms developed for predicting the structure of proteins, in particular AlphaFold, an AI which claims to have solved the problem of protein structure. In a recent study, we highlighted a particular weakness of AlphaFold for membrane proteins. Based on this observation, we have proposed a paradigm, referred to as “Epigenetic Dimension of Protein Structure” (EDPS), which takes into account all environmental parameters that control the structure of a protein beyond the amino acid sequence (hence “epigenetic”). In this new study, we compare the reliability of the AlphaFold and Robetta algorithms’ predictions for a new set of membrane proteins involved in human pathologies. We found that Robetta was generally more accurate than AlphaFold for ascribing a membrane-compatible topology. Raft lipids (e.g., gangliosides), which control the structural dynamics of membrane protein structure through chaperone effects, were identified as major actors of the EDPS paradigm. We conclude that the epigenetic dimension of a protein structure is an intrinsic weakness of AI-based protein structure prediction, especially AlphaFold, which warrants further development.
Collapse
|
14
|
Fuladi S, McGuinness S, Khalili-Araghi F. Role of TM3 in claudin-15 strand flexibility: A molecular dynamics study. Front Mol Biosci 2022; 9:964877. [PMID: 36250014 PMCID: PMC9557151 DOI: 10.3389/fmolb.2022.964877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 08/22/2022] [Indexed: 11/13/2022] Open
Abstract
Claudins are cell-cell adhesion proteins within tight junctions that connect epithelial cells together. Claudins polymerize into a network of strand-like structures within the membrane of adjoining cells and create ion channels that control paracellular permeability to water and small molecules. Tight junction morphology and barrier function is tissue specific and regulated by claudin subtypes. Here, we present a molecular dynamics study of claudin-15 strands within lipid membranes and the role of a single-point mutation (A134P) on the third transmembrane helix (TM3) of claudin-15 in determining the morphology of the strand. Our results indicate that the A134P mutation significantly affects the lateral flexibility of the strands, increasing the persistence length of claudin-15 strands by a factor of three. Analyses of claudin-claudin contact in our μsecond-long trajectories show that the mutation does not alter the intermolecular contacts (interfaces) between claudins. However, the dynamics and frequency of interfacial contacts are significantly affected. The A134P mutation introduces a kink in TM3 of claudin-15 similar to the one observed in claudin-3 crystal structure. The kink on TM3 skews the rotational flexibility of the claudins in the strands and limits their fluctuation in one direction. This asymmetric movement in the context of the double rows reduces the lateral flexibility of the strand and leads to higher persistence lengths of the mutant.
Collapse
Affiliation(s)
- Shadi Fuladi
- Department of Physics, University of Illinois at Chicago, Chicago, IL, United States
| | - Sarah McGuinness
- Department of Bioengineering, University of Illinois at Chicago, Chicago, IL, United States
| | | |
Collapse
|
15
|
Sharma GP, Meyer AC, Habeeb S, Karbach M, Müller G. Free-energy landscapes and insertion pathways for peptides in membrane environment. Phys Rev E 2022; 106:014404. [PMID: 35974613 DOI: 10.1103/physreve.106.014404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 07/04/2022] [Indexed: 06/15/2023]
Abstract
Free-energy landscapes for short peptides-specifically for variants of the pH low insertion peptide (pHLIP)-in the heterogeneous environment of a lipid bilayer or cell membrane are constructed, taking into account a set of dominant interactions and the conformational preferences of the peptide backbone. Our methodology interprets broken internal H-bonds along the backbone of a polypeptide as statistically interacting quasiparticles, activated from the helix reference state. The favored conformation depends on the local environment (ranging from polar to nonpolar), specifically on the availability of external H-bonds (with H_{2}O molecules or lipid headgroups) to replace internal H-bonds. The dominant side-chain contribution is accounted for by residue-specific transfer free energies between polar and nonpolar environments. The free-energy landscape is sensitive to the level of pH in the aqueous environment surrounding the membrane. For high pH, we identify pathways of descending free energy that suggest a coexistence of membrane-adsorbed peptides with peptides in solution. A drop in pH raises the degree of protonation of negatively charged residues and thus increases the hydrophobicity of peptide segments near the C terminus. For low pH, we identify insertion pathways between the membrane-adsorbed state and a stable trans-membrane state with the C terminus having crossed the membrane.
Collapse
Affiliation(s)
- Ganga P Sharma
- Department of Physics, University of Rhode Island, Kingston, Rhode Island 02881, USA
| | - Aaron C Meyer
- Department of Physics, University of Rhode Island, Kingston, Rhode Island 02881, USA
| | - Suhail Habeeb
- Department of Physics, University of Rhode Island, Kingston, Rhode Island 02881, USA
| | - Michael Karbach
- Fachgruppe Physik, Bergische Universität Wuppertal, D-42097 Wuppertal, Germany
| | - Gerhard Müller
- Department of Physics, University of Rhode Island, Kingston, Rhode Island 02881, USA
| |
Collapse
|
16
|
Puthumadathil N, Krishnan R S, Nair GS, Mahendran KR. Assembly of alpha-helical transmembrane pores through an intermediate state. NANOSCALE 2022; 14:6507-6517. [PMID: 35420118 DOI: 10.1039/d2nr00556e] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Pore-forming alpha-helical proteins are well known for their dynamic assembly mechanism and it has been challenging to delineate the pore-forming structures in membranes. Previously, attempts have been made to elucidate their assembly mechanism and there is a large gap due to complex pathways by which these membrane-active pores impart their effect. Here we demonstrate a multi-step structural assembly pathway of alpha-helical peptide pores formed by a 37 amino acid synthetic peptide, pPorU, based on the natural porin from Corynebacterium urealyticum using single-channel electrical recordings. More specifically, we report detectable intermediate states during the membrane insertion and pore formation of pPorU. The fully assembled pore exhibited unusually large stable conductance, voltage-dependent gating, and functional blockage by cyclic sugars generally applicable to a range of transmembrane pores. Furthermore, we used rationally designed mutants to understand the role of specific amino acids in the assembly of these peptide pores. Mutant peptides that differ from wild-type peptides produced noisy and unstable intermediate states and low conductance pores, demonstrating sequence specificity in the pore-formation process supported by molecular dynamics simulations. We suggest that our study contributes to understanding the mechanism of action of naturally occurring alpha-helical pore-forming proteins and should be of broad interest to build peptide-based nanopore sensors.
Collapse
Affiliation(s)
- Neethu Puthumadathil
- Membrane Biology Laboratory, Transdisciplinary Research Program, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram 695014, India.
- Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India
| | - Smrithi Krishnan R
- Membrane Biology Laboratory, Transdisciplinary Research Program, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram 695014, India.
- Manipal Academy of Higher Education, Manipal, Karnataka, 576104, India
| | - Greeshma S Nair
- Membrane Biology Laboratory, Transdisciplinary Research Program, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram 695014, India.
| | - Kozhinjampara R Mahendran
- Membrane Biology Laboratory, Transdisciplinary Research Program, Rajiv Gandhi Centre for Biotechnology, Thiruvananthapuram 695014, India.
| |
Collapse
|
17
|
Reddy UV, Weber DK, Wang S, Larsen EK, Gopinath T, De Simone A, Robia S, Veglia G. A kink in DWORF helical structure controls the activation of the sarcoplasmic reticulum Ca 2+-ATPase. Structure 2022; 30:360-370.e6. [PMID: 34875216 PMCID: PMC8897251 DOI: 10.1016/j.str.2021.11.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 09/14/2021] [Accepted: 11/11/2021] [Indexed: 12/31/2022]
Abstract
SERCA is a P-type ATPase embedded in the sarcoplasmic reticulum and plays a central role in muscle relaxation. SERCA's function is regulated by single-pass membrane proteins called regulins. Unlike other regulins, dwarf open reading frame (DWORF) expressed in cardiac muscle has a unique activating effect. Here, we determine the structure and topology of DWORF in lipid bilayers using a combination of oriented sample solid-state NMR spectroscopy and replica-averaged orientationally restrained molecular dynamics. We found that DWORF's structural topology consists of a dynamic N-terminal domain, an amphipathic juxtamembrane helix that crosses the lipid groups at an angle of 64°, and a transmembrane C-terminal helix with an angle of 32°. A kink induced by Pro15, unique to DWORF, separates the two helical domains. A single Pro15Ala mutant significantly decreases the kink and eliminates DWORF's activating effect on SERCA. Overall, our findings directly link DWORF's structural topology to its activating effect on SERCA.
Collapse
Affiliation(s)
- U. Venkateswara Reddy
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Daniel K. Weber
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Songlin Wang
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Erik K. Larsen
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, USA
| | - Tata Gopinath
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Alfonso De Simone
- Department of Life Sciences, Imperial College London, South Kensington, London, SW7 2AZ, UK,Department of Pharmacy, University of Naples “Federico II”, Naples, 80131, Italy
| | - Seth Robia
- Department of Cell and Molecular Physiology, Loyola University Chicago, Maywood, IL 60153, USA
| | - Gianluigi Veglia
- Department of Biochemistry, Molecular Biology, and Biophysics, University of Minnesota, 6-155 Jackson Hall, Minneapolis, MN 55455, USA; Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, USA.
| |
Collapse
|
18
|
Langer I, Jeandriens J, Couvineau A, Sanmukh S, Latek D. Signal Transduction by VIP and PACAP Receptors. Biomedicines 2022; 10:biomedicines10020406. [PMID: 35203615 PMCID: PMC8962308 DOI: 10.3390/biomedicines10020406] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 02/03/2022] [Accepted: 02/04/2022] [Indexed: 02/05/2023] Open
Abstract
Homeostasis of the human immune system is regulated by many cellular components, including two neuropeptides, VIP and PACAP, primary stimuli for three class B G protein-coupled receptors, VPAC1, VPAC2, and PAC1. Vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase-activating polypeptide (PACAP) regulate intestinal motility and secretion and influence the functioning of the endocrine and immune systems. Inhibition of VIP and PACAP receptors is an emerging concept for new pharmacotherapies for chronic inflammation and cancer, while activation of their receptors provides neuroprotection. A small number of known active compounds for these receptors still impose limitations on their use in therapeutics. Recent cryo-EM structures of VPAC1 and PAC1 receptors in their agonist-bound active state have provided insights regarding their mechanism of activation. Here, we describe major molecular switches of VPAC1, VPAC2, and PAC1 that may act as triggers for receptor activation and compare them with similar non-covalent interactions changing upon activation that were observed for other GPCRs. Interhelical interactions in VIP and PACAP receptors that are important for agonist binding and/or activation provide a molecular basis for the design of novel selective drugs demonstrating anti-inflammatory, anti-cancer, and neuroprotective effects. The impact of genetic variants of VIP, PACAP, and their receptors on signalling mediated by endogenous agonists is also described. This sequence diversity resulting from gene splicing has a significant impact on agonist selectivity and potency as well as on the signalling properties of VIP and PACAP receptors.
Collapse
Affiliation(s)
- Ingrid Langer
- Institut de Recherche Interdisciplinaire en Biologie Humaine et Moléculaire (IRIBHM), Université libre de Bruxelles, B-1070 Brussels, Belgium; (I.L.); (J.J.)
| | - Jérôme Jeandriens
- Institut de Recherche Interdisciplinaire en Biologie Humaine et Moléculaire (IRIBHM), Université libre de Bruxelles, B-1070 Brussels, Belgium; (I.L.); (J.J.)
| | - Alain Couvineau
- UMR 1149 Inserm, Centre de Recherche sur l’Inflammation (CRI), Université de Paris, 75018 Paris, France;
| | - Swapnil Sanmukh
- Faculty of Chemistry, University of Warsaw, 02-093 Warsaw, Poland;
| | - Dorota Latek
- Faculty of Chemistry, University of Warsaw, 02-093 Warsaw, Poland;
- Correspondence:
| |
Collapse
|
19
|
Ledoux J, Trouvé A, Tchertanov L. The Inherent Coupling of Intrinsically Disordered Regions in the Multidomain Receptor Tyrosine Kinase KIT. Int J Mol Sci 2022; 23:ijms23031589. [PMID: 35163518 PMCID: PMC8835827 DOI: 10.3390/ijms23031589] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Revised: 01/24/2022] [Accepted: 01/26/2022] [Indexed: 02/04/2023] Open
Abstract
RTK KIT regulates a variety of crucial cellular processes via its cytoplasmic domain (CD), which is composed of the tyrosine kinase domain, crowned by the highly flexible domains—the juxtamembrane region, kinase insertion domain, and C-tail, which are key recruitment regions for downstream signalling proteins. To prepare a structural basis for the characterization of the interactions of KIT with its signalling proteins (KIT INTERACTOME), we generated the 3D model of the full-length CD attached to the transmembrane helix. This generic model of KIT in inactive state was studied by molecular dynamics simulation under conditions mimicking the natural environment of KIT. With the accurate atomistic description of the multidomain KIT dynamics, we explained its intrinsic (intra-domain) and extrinsic (inter-domain) disorder and represented the conformational assemble of KIT through free energy landscapes. Strongly coupled movements within each domain and between distant domains of KIT prove the functional interdependence of these regions, described as allosteric regulation, a phenomenon widely observed in many proteins. We suggested that KIT, in its inactive state, encodes all properties of the active protein and its post-transduction events.
Collapse
|
20
|
Clinical, Genetic and Functional Characterization of a Novel AVPR2 Missense Mutation in a Woman with X-Linked Recessive Nephrogenic Diabetes Insipidus. J Pers Med 2022; 12:jpm12010118. [PMID: 35055433 PMCID: PMC8779739 DOI: 10.3390/jpm12010118] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 12/27/2021] [Accepted: 01/05/2022] [Indexed: 11/28/2022] Open
Abstract
Nephrogenic diabetes insipidus (NDI) is a rare disorder characterized by renal unresponsiveness to the hormone vasopressin, leading to excretion of large volumes of diluted urine. Mutations in the arginine vasopressin receptor-2 (AVPR2) gene cause congenital NDI and have an X-linked recessive inheritance. The disorder affects almost exclusively male family members, but female carriers occasionally present partial phenotypes due to skewed inactivation of the X-chromosome. Here, we report a rare case of a woman affected with X-linked recessive NDI, presenting an average urinary output of 12 L/day. Clinical and biochemical studies showed incomplete responses to water deprivation and vasopressin stimulation tests. Genetic analyses revealed a novel heterozygous missense mutation (c.493G > C, p.Ala165Pro) in the AVPR2 gene. Using a combination of in-silico protein modeling with human cellular models and molecular phenotyping, we provide functional evidence for phenotypic effects. The mutation destabilizes the helical structure of the AVPR2 transmembrane domains and disrupts its plasma membrane localization and downstream intracellular signaling pathways upon activation with its agonist vasopressin. These defects lead to deficient aquaporin 2 (AQP2) membrane translocation, explaining the inability to concentrate urine in this patient.
Collapse
|
21
|
Huo J, Lu BZ, Dong H. Mutants only partially represent characteristics of calcium-release-activated calcium channel gating. CHINESE J CHEM PHYS 2021. [DOI: 10.1063/1674-0068/cjcp2111231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Jun Huo
- Kuang Yaming Honors School, Nanjing University, Nanjing 210023, China
| | - Ben-zhuo Lu
- CEMS, LSEC, NCMIS, Academy of Mathematics and Systems Science, Chinese Academy of Sciences; School of Mathematical Sciences, University of Chinese Academy of Sciences, Beijing 100190, China
| | - Hao Dong
- Kuang Yaming Honors School, Nanjing University, Nanjing 210023, China
- Institute for Brain Sciences, Nanjing University, Nanjing 210023, China
- State Key Laboratory of Analytical Chemistry for Life Science, Nanjing University, Nanjing 210023, China
- Engineering Research Center of Protein and Peptide Medicine of Ministry of Education, Nanjing University, Nanjing 210023, China
| |
Collapse
|
22
|
Guha S, Ferrie RP, Ghimire J, Ventura CR, Wu E, Sun L, Kim SY, Wiedman GR, Hristova K, Wimley WC. Applications and evolution of melittin, the quintessential membrane active peptide. Biochem Pharmacol 2021; 193:114769. [PMID: 34543656 DOI: 10.1016/j.bcp.2021.114769] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 09/14/2021] [Accepted: 09/15/2021] [Indexed: 12/12/2022]
Abstract
Melittin, the main venom component of the European Honeybee, is a cationic linear peptide-amide of 26 amino acid residues with the sequence: GIGAVLKVLTTGLPALISWIKRKRQQ-NH2. Melittin binds to lipid bilayer membranes, folds into amphipathic α-helical secondary structure and disrupts the permeability barrier. Since melittin was first described, a remarkable array of activities and potential applications in biology and medicine have been described. Melittin is also a favorite model system for biophysicists to study the structure, folding and function of peptides and proteins in membranes. Melittin has also been used as a template for the evolution of new activities in membranes. Here we overview the rich history of scientific research into the many activities of melittin and outline exciting future applications.
Collapse
Affiliation(s)
- Shantanu Guha
- University of Texas Health Science Center at Houston, Department of Microbiology and Molecular Genetics, Houston, TX, USA
| | - Ryan P Ferrie
- Tulane University School of Medicine, Department of Biochemistry and Molecular Biology, New Orleans, LA, USA
| | - Jenisha Ghimire
- Tulane University School of Medicine, Department of Biochemistry and Molecular Biology, New Orleans, LA, USA
| | - Cristina R Ventura
- Seton Hall University, Department of Chemistry and Biochemistry, South Orange, NJ, USA
| | - Eric Wu
- Tulane University School of Medicine, Department of Biochemistry and Molecular Biology, New Orleans, LA, USA
| | - Leisheng Sun
- Tulane University School of Medicine, Department of Biochemistry and Molecular Biology, New Orleans, LA, USA
| | - Sarah Y Kim
- Duke University, Department of Biomedical Engineering, Durham, NC, USA
| | - Gregory R Wiedman
- Seton Hall University, Department of Chemistry and Biochemistry, South Orange, NJ, USA
| | - Kalina Hristova
- Johns Hopkins University, Department of Materials Science and Engineering, Baltimore, MD, USA.
| | - Wimley C Wimley
- University of Texas Health Science Center at Houston, Department of Microbiology and Molecular Genetics, Houston, TX, USA.
| |
Collapse
|
23
|
Tsitrina AA, Krasylov IV, Maltsev DI, Andreichenko IN, Moskvina VS, Ivankov DN, Bulgakova EV, Nesterchuk M, Shashkovskaya V, Dashenkova NO, Khilya VP, Mikaelyan A, Kotelevtsev Y. Inhibition of hyaluronan secretion by novel coumarin compounds and chitin synthesis inhibitors. Glycobiology 2021; 31:959-974. [PMID: 33978736 PMCID: PMC8434796 DOI: 10.1093/glycob/cwab038] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Revised: 04/20/2021] [Accepted: 04/20/2021] [Indexed: 02/07/2023] Open
Abstract
Elevated plasma levels of hyaluronic acid (HA) is a disease marker in liver pathology and other inflammatory disorders. Inhibition of HA synthesis with coumarin 4-methylumbelliferone (4MU) has a beneficial effect in animal models of fibrosis, inflammation, cancer and metabolic syndrome. 4MU is an active compound of approved choleretic drug hymecromone with low bioavailability and a broad spectrum of action. New, more specific and efficient inhibitors of hyaluronan synthases (HAS) are required. We have tested several newly synthesized coumarin compounds and commercial chitin synthesis inhibitors to inhibit HA production in cell culture assay. Coumarin derivative compound VII (10'-methyl-6'-phenyl-3'H-spiro[piperidine-4,2'-pyrano[3,2-g]chromene]-4',8'-dione) demonstrated inhibition of HA secretion by NIH3T3 cells with the half-maximal inhibitory concentration (IC50) = 1.69 ± 0.75 μΜ superior to 4MU (IC50 = 8.68 ± 1.6 μΜ). Inhibitors of chitin synthesis, etoxazole, buprofezin, triflumuron, reduced HA deposition with IC50 of 4.21 ± 3.82 μΜ, 1.24 ± 0.87 μΜ and 1.48 ± 1.44 μΜ, respectively. Etoxazole reduced HA production and prevented collagen fibre formation in the CCl4 liver fibrosis model in mice similar to 4MU. Bioinformatics analysis revealed homology between chitin synthases and HAS enzymes, particularly in the pore-forming domain, containing the proposed site for etoxazole binding.
Collapse
Affiliation(s)
- Alexandra A Tsitrina
- Laboratory of problems of regeneration, Koltzov Institute of Developmental Biology of Russian Academy of Sciences, 119334 Moscow, Russia
| | - Igor V Krasylov
- Department of Organic Chemistry, Taras Shevchenko National University of Kyiv, 01601 Kyiv, Ukraine
| | - Dmitry I Maltsev
- Laboratory of problems of regeneration, Koltzov Institute of Developmental Biology of Russian Academy of Sciences, 119334 Moscow, Russia
| | - Irina N Andreichenko
- Center for Neurobiology and Brain Restoration and Center of Life Sciences, Skolkovo Institute of Science and Technology, Skolkovo, 143025 Moscow, Russia
| | - Viktoria S Moskvina
- Department of Organic Chemistry, Taras Shevchenko National University of Kyiv, 01601 Kyiv, Ukraine
| | - Dmitry N Ivankov
- Center for Neurobiology and Brain Restoration and Center of Life Sciences, Skolkovo Institute of Science and Technology, Skolkovo, 143025 Moscow, Russia
| | - Elena V Bulgakova
- Laboratory of problems of regeneration, Koltzov Institute of Developmental Biology of Russian Academy of Sciences, 119334 Moscow, Russia
| | - Mikhail Nesterchuk
- Center for Neurobiology and Brain Restoration and Center of Life Sciences, Skolkovo Institute of Science and Technology, Skolkovo, 143025 Moscow, Russia
| | - Vera Shashkovskaya
- Center for Neurobiology and Brain Restoration and Center of Life Sciences, Skolkovo Institute of Science and Technology, Skolkovo, 143025 Moscow, Russia
| | - Nataliya O Dashenkova
- Laboratory of problems of regeneration, Koltzov Institute of Developmental Biology of Russian Academy of Sciences, 119334 Moscow, Russia
| | - Vladimir P Khilya
- Department of Organic Chemistry, Taras Shevchenko National University of Kyiv, 01601 Kyiv, Ukraine
| | - Arsen Mikaelyan
- Laboratory of problems of regeneration, Koltzov Institute of Developmental Biology of Russian Academy of Sciences, 119334 Moscow, Russia
| | - Yuri Kotelevtsev
- Center for Neurobiology and Brain Restoration and Center of Life Sciences, Skolkovo Institute of Science and Technology, Skolkovo, 143025 Moscow, Russia
| |
Collapse
|
24
|
Bründl M, Pellikan S, Stary-Weinzinger A. Simulating PIP 2-Induced Gating Transitions in Kir6.2 Channels. Front Mol Biosci 2021; 8:711975. [PMID: 34447786 PMCID: PMC8384051 DOI: 10.3389/fmolb.2021.711975] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2021] [Accepted: 07/08/2021] [Indexed: 11/13/2022] Open
Abstract
ATP-sensitive potassium (KATP) channels consist of an inwardly rectifying K+ channel (Kir6.2) pore, to which four ATP-sensitive sulfonylurea receptor (SUR) domains are attached, thereby coupling K+ permeation directly to the metabolic state of the cell. Dysfunction is linked to neonatal diabetes and other diseases. K+ flux through these channels is controlled by conformational changes in the helix bundle region, which acts as a physical barrier for K+ permeation. In addition, the G-loop, located in the cytoplasmic domain, and the selectivity filter might contribute to gating, as suggested by different disease-causing mutations. Gating of Kir channels is regulated by different ligands, like Gβγ, H+, Na+, adenosine nucleotides, and the signaling lipid phosphatidyl-inositol 4,5-bisphosphate (PIP2), which is an essential activator for all eukaryotic Kir family members. Although molecular determinants of PIP2 activation of KATP channels have been investigated in functional studies, structural information of the binding site is still lacking as PIP2 could not be resolved in Kir6.2 cryo-EM structures. In this study, we used Molecular Dynamics (MD) simulations to examine the dynamics of residues associated with gating in Kir6.2. By combining this structural information with functional data, we investigated the mechanism underlying Kir6.2 channel regulation by PIP2.
Collapse
Affiliation(s)
| | | | - Anna Stary-Weinzinger
- Department of Pharmaceutical Sciences, Division of Pharmacology and Toxicology, University of Vienna, Vienna, Austria
| |
Collapse
|
25
|
Liu Y, Mao C, Liu S, Xiao D, Shi Y, Tao Y. Proline dehydrogenase in cancer: apoptosis, autophagy, nutrient dependency and cancer therapy. Amino Acids 2021; 53:1891-1902. [PMID: 34283310 DOI: 10.1007/s00726-021-03032-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 06/27/2021] [Indexed: 01/03/2023]
Abstract
L-proline catabolism is emerging as a key pathway that is critical to cellular metabolism, growth, survival, and death. Proline dehydrogenase (PRODH) enzyme, which catalyzes the first step of proline catabolism, has diverse functional roles in regulating many pathophysiological processes, including apoptosis, autophagy, cell senescence, and cancer metastasis. Notably, accumulated evidence demonstrated that PRODH plays complex role in many types of cancers. In this review, we briefly introduce the function of PRODH, then its expression in different types of cancer. We next discuss the regulation of PRODH in cancer, the downstream pathways of PRODH and the therapies that are under investigation. Finally, we propose novel insights for future perspectives on the modulation of PRODH.
Collapse
Affiliation(s)
- Yating Liu
- Postdoctoral Research Station of Clinical Medicine & Department of Hematology and Critical Care Medicine, Central South University, the 3rd Xiangya Hospital, Changsha, 410000, People's Republic of China.,Department of Pathology, Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Xiangya Hospital, Central South University, Hunan, 410078, China.,NHC Key Laboratory of Carcinogenesis (Central South University), Cancer Research Institute and School of Basic Medicine, Central South University, Changsha, 410078, Hunan, China
| | - Chao Mao
- Department of Pathology, Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Xiangya Hospital, Central South University, Hunan, 410078, China.,NHC Key Laboratory of Carcinogenesis (Central South University), Cancer Research Institute and School of Basic Medicine, Central South University, Changsha, 410078, Hunan, China
| | - Shuang Liu
- Department of Oncology, Institute of Medical Sciences, Center for Geriatric Disorders, National Clinical Research, Xiangya Hospital, Central South University, Changsha, 410008, Hunan, China
| | - Desheng Xiao
- Department of Pathology, Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Xiangya Hospital, Central South University, Hunan, 410078, China. .,NHC Key Laboratory of Carcinogenesis (Central South University), Cancer Research Institute and School of Basic Medicine, Central South University, Changsha, 410078, Hunan, China.
| | - Ying Shi
- Department of Pathology, Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Xiangya Hospital, Central South University, Hunan, 410078, China. .,NHC Key Laboratory of Carcinogenesis (Central South University), Cancer Research Institute and School of Basic Medicine, Central South University, Changsha, 410078, Hunan, China.
| | - Yongguang Tao
- Department of Pathology, Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Xiangya Hospital, Central South University, Hunan, 410078, China. .,NHC Key Laboratory of Carcinogenesis (Central South University), Cancer Research Institute and School of Basic Medicine, Central South University, Changsha, 410078, Hunan, China. .,Hunan Key Laboratory of Early Diagnosis and Precision Therapy in Lung Cancer, Second Xiangya Hospital, Central South University, Changsha, 410011, China.
| |
Collapse
|
26
|
Principles and Methods in Computational Membrane Protein Design. J Mol Biol 2021; 433:167154. [PMID: 34271008 DOI: 10.1016/j.jmb.2021.167154] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2021] [Revised: 07/03/2021] [Accepted: 07/06/2021] [Indexed: 01/13/2023]
Abstract
After decades of progress in computational protein design, the design of proteins folding and functioning in lipid membranes appears today as the next frontier. Some notable successes in the de novo design of simplified model membrane protein systems have helped articulate fundamental principles of protein folding, architecture and interaction in the hydrophobic lipid environment. These principles are reviewed here, together with the computational methods and approaches that were used to identify them. We provide an overview of the methodological innovations in the generation of new protein structures and functions and in the development of membrane-specific energy functions. We highlight the opportunities offered by new machine learning approaches applied to protein design, and by new experimental characterization techniques applied to membrane proteins. Although membrane protein design is in its infancy, it appears more reachable than previously thought.
Collapse
|
27
|
Zhai H, Zheng Y, He Y, Zhang Y, Guo Z, Cui W, Sun L. A case report of infantile parkinsonism-dystonia-2 caused by homozygous mutation in the SLC18A2 gene. Int J Neurosci 2021; 133:574-577. [PMID: 34078222 DOI: 10.1080/00207454.2021.1938036] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Background: The monoamine neurotransmitter disorders are neurometabolic syndromes caused by disturbances in the synthesis, transport and metabolism of the biogenic amines (the catecholamines dopamine, norepinephrine and epinephrine; serotonin), which are increasingly recognized as an expanding group of inherited neurometabolic syndromes.Case Description: A 6-month-old male infant who presented with developmental delay and suspected cerebral palsy was diagnosed with infantile parkinsonism-dystonia-2 (MIM: 618049). The whole-exome sequencing identified a homozygous c.710C > T (p.Pro237His) transition in the monoamine transporter gene SLC18A2, which was due to paternal uniparental disomy (UPD) of chromosome 10p15.3q26.3, resulting in brain dopamine-serotonin vesicular transport disease. Sanger sequencing confirmed that his unaffected father carried the same mutation in the heterozygous state, while his mother did not carry the same mutation. Autosomal recessive gene mutations in SLC18A2 has been identified in three families in different countries. The infant was treated with pramipexole, a dopamine agonist, and the static tremor was better compared with that before treatment, but the movement disorder was not significantly improved.Conclusion: This case confirmed the causal mutation of SLC18A2 gene and brain dopamine-serotonin vesicular transport disease, which suggested the mechanism of UPD homozygous formation, and confirmed that dopamine agonist treatment could improve some symptoms in affected individuals.
Collapse
Affiliation(s)
- Hongyin Zhai
- Rehabilitation and Treatment Centre for Cerebral Palsy, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
| | - Yaofeng Zheng
- Guangzhou Jiajian Check Medicine, Guangzhou, Guangdong Province, China
| | - Yiduo He
- Guangzhou Jiajian Check Medicine, Guangzhou, Guangdong Province, China
| | - Yong Zhang
- Rehabilitation and Treatment Centre for Cerebral Palsy, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
| | - Zhikuan Guo
- Rehabilitation and Treatment Centre for Cerebral Palsy, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
| | - Wenzhe Cui
- Rehabilitation and Treatment Centre for Cerebral Palsy, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
| | - Li Sun
- Rehabilitation and Treatment Centre for Cerebral Palsy, The Third Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan Province, China
| |
Collapse
|
28
|
Beckham KSH, Ritter C, Chojnowski G, Ziemianowicz DS, Mullapudi E, Rettel M, Savitski MM, Mortensen SA, Kosinski J, Wilmanns M. Structure of the mycobacterial ESX-5 type VII secretion system pore complex. SCIENCE ADVANCES 2021; 7:eabg9923. [PMID: 34172453 PMCID: PMC8232910 DOI: 10.1126/sciadv.abg9923] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 05/10/2021] [Indexed: 05/28/2023]
Abstract
The ESX-5 type VII secretion system is a membrane-spanning protein complex key to the virulence of mycobacterial pathogens. However, the overall architecture of the fully assembled translocation machinery and the composition of the central secretion pore have remained unknown. Here, we present the high-resolution structure of the 2.1-megadalton ESX-5 core complex. Our structure captured a dynamic, secretion-competent conformation of the pore within a well-defined transmembrane section, sandwiched between two flexible protein layers at the cytosolic entrance and the periplasmic exit. We propose that this flexibility endows the ESX-5 machinery with large conformational plasticity required to accommodate targeted protein secretion. Compared to known secretion systems, a highly dynamic state of the pore may represent a fundamental principle of bacterial secretion machineries.
Collapse
Affiliation(s)
- Katherine S H Beckham
- European Molecular Biology Laboratory, Hamburg Unit, Notkestrasse 85, 22607 Hamburg, Germany
| | - Christina Ritter
- European Molecular Biology Laboratory, Hamburg Unit, Notkestrasse 85, 22607 Hamburg, Germany
| | - Grzegorz Chojnowski
- European Molecular Biology Laboratory, Hamburg Unit, Notkestrasse 85, 22607 Hamburg, Germany
| | - Daniel S Ziemianowicz
- European Molecular Biology Laboratory, Hamburg Unit, Notkestrasse 85, 22607 Hamburg, Germany
| | - Edukondalu Mullapudi
- European Molecular Biology Laboratory, Hamburg Unit, Notkestrasse 85, 22607 Hamburg, Germany
| | - Mandy Rettel
- European Molecular Biology Laboratory, Heidelberg, Germany
| | | | - Simon A Mortensen
- European Molecular Biology Laboratory, Hamburg Unit, Notkestrasse 85, 22607 Hamburg, Germany
| | - Jan Kosinski
- European Molecular Biology Laboratory, Hamburg Unit, Notkestrasse 85, 22607 Hamburg, Germany.
- Centre for Structural Systems Biology (CSSB), Hamburg, Germany
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Matthias Wilmanns
- European Molecular Biology Laboratory, Hamburg Unit, Notkestrasse 85, 22607 Hamburg, Germany.
- University Hamburg Clinical Centre Hamburg-Eppendorf, Martinistrasse 52, 20246 Hamburg, Germany
| |
Collapse
|
29
|
Human ACE2 peptide-mimics block SARS-CoV-2 pulmonary cells infection. Commun Biol 2021; 4:197. [PMID: 33580154 PMCID: PMC7881012 DOI: 10.1038/s42003-021-01736-8] [Citation(s) in RCA: 81] [Impact Index Per Article: 27.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 01/20/2021] [Indexed: 12/13/2022] Open
Abstract
In light of the recent accumulated knowledge on SARS-CoV-2 and its mode of human cells invasion, the binding of viral spike glycoprotein to human Angiotensin Converting Enzyme 2 (hACE2) receptor plays a central role in cell entry. We designed a series of peptides mimicking the N-terminal helix of hACE2 protein which contains most of the contacting residues at the binding site, exhibiting a high helical folding propensity in aqueous solution. Our best peptide-mimics are able to block SARS-CoV-2 human pulmonary cell infection with an inhibitory concentration (IC50) in the nanomolar range upon binding to the virus spike protein with high affinity. These first-in-class blocking peptide mimics represent powerful tools that might be used in prophylactic and therapeutic approaches to fight the coronavirus disease 2019 (COVID-19). Karoyan et al. present a method to inhibit SARS-CoV-2 by means of a peptide-mimic approach. They design a series of peptides mimicking the N-terminal helix of hACE2 protein and their best peptide-mimic blocks SARS-CoV-2 human pulmonary cell infection with an IC50 in nanomolar range.
Collapse
|
30
|
Glatzová D, Mavila H, Saija MC, Chum T, Cwiklik L, Brdička T, Cebecauer M. The role of prolines and glycine in the transmembrane domain of LAT. FEBS J 2021; 288:4039-4052. [PMID: 33458942 DOI: 10.1111/febs.15713] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 12/15/2020] [Accepted: 01/13/2021] [Indexed: 12/30/2022]
Abstract
Linker for activation in T cells (LAT) is a critical regulator of T-cell development and function. It organises signalling events at the plasma membrane. However, the mechanism, which controls LAT localisation at the plasma membrane, is not fully understood. Here, we studied the impact of helix-breaking amino acids, two prolines and one glycine, in the transmembrane segment on localisation and function of LAT. Using in silico analysis, confocal and super-resolution imaging and flow cytometry, we demonstrate that central proline residue destabilises transmembrane helix by inducing a kink. The helical structure and dynamics are further regulated by glycine and another proline residue in the luminal part of LAT transmembrane domain. Replacement of these residues with aliphatic amino acids reduces LAT dependence on palmitoylation for sorting to the plasma membrane. However, surface expression of these mutants is not sufficient to recover function of nonpalmitoylated LAT in stimulated T cells. These data indicate that geometry and dynamics of LAT transmembrane segment regulate its localisation and function in immune cells.
Collapse
Affiliation(s)
- Daniela Glatzová
- Department of Biophysical Chemistry, J. Heyrovsky Institute of Physical Chemistry, Czech Academy of Sciences, Prague, Czech Republic.,Laboratory of Leukocyte Signaling, Institute of Molecule Genetics, Czech Academy of Sciences, Prague, Czech Republic.,Faculty of Science, Charles University, Prague, Czech Republic
| | - Harsha Mavila
- Department of Biophysical Chemistry, J. Heyrovsky Institute of Physical Chemistry, Czech Academy of Sciences, Prague, Czech Republic
| | - Maria Chiara Saija
- Department of Computational Chemistry, J. Heyrovsky Institute of Physical Chemistry, Czech Academy of Sciences, Prague, Czech Republic
| | - Tomáš Chum
- Department of Biophysical Chemistry, J. Heyrovsky Institute of Physical Chemistry, Czech Academy of Sciences, Prague, Czech Republic
| | - Lukasz Cwiklik
- Department of Computational Chemistry, J. Heyrovsky Institute of Physical Chemistry, Czech Academy of Sciences, Prague, Czech Republic
| | - Tomáš Brdička
- Laboratory of Leukocyte Signaling, Institute of Molecule Genetics, Czech Academy of Sciences, Prague, Czech Republic
| | - Marek Cebecauer
- Department of Biophysical Chemistry, J. Heyrovsky Institute of Physical Chemistry, Czech Academy of Sciences, Prague, Czech Republic
| |
Collapse
|
31
|
Maschio MC, Fregoni J, Molteni C, Corni S. Proline isomerization effects in the amyloidogenic protein β2-microglobulin. Phys Chem Chem Phys 2021; 23:356-367. [DOI: 10.1039/d0cp04780e] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The protein β2-microglobulin can aggregate in insoluble amyloid fibrils. By relying on extensive sampling simulations, we study the Pro32 isomerization as a possible triggering factor leading to structural modifications in β2-m.
Collapse
Affiliation(s)
| | - Jacopo Fregoni
- CNR-Nano S3
- Modena
- Italy
- Department of Chemical Sciences
- University of Padova
| | - Carla Molteni
- Department of Physics
- King's College London
- Strand
- London WC2R 2LS
- UK
| | - Stefano Corni
- CNR-Nano S3
- Modena
- Italy
- Department of Chemical Sciences
- University of Padova
| |
Collapse
|
32
|
Spitz C, Schlosser C, Guschtschin-Schmidt N, Stelzer W, Menig S, Götz A, Haug-Kröper M, Scharnagl C, Langosch D, Muhle-Goll C, Fluhrer R. Non-canonical Shedding of TNFα by SPPL2a Is Determined by the Conformational Flexibility of Its Transmembrane Helix. iScience 2020; 23:101775. [PMID: 33294784 PMCID: PMC7689174 DOI: 10.1016/j.isci.2020.101775] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 10/21/2020] [Accepted: 11/03/2020] [Indexed: 12/22/2022] Open
Abstract
Ectodomain (EC) shedding defines the proteolytic removal of a membrane protein EC and acts as an important molecular switch in signaling and other cellular processes. Using tumor necrosis factor (TNF)α as a model substrate, we identify a non-canonical shedding activity of SPPL2a, an intramembrane cleaving aspartyl protease of the GxGD type. Proline insertions in the TNFα transmembrane (TM) helix strongly increased SPPL2a non-canonical shedding, while leucine mutations decreased this cleavage. Using biophysical and structural analysis, as well as molecular dynamic simulations, we identified a flexible region in the center of the TNFα wildtype TM domain, which plays an important role in the processing of TNFα by SPPL2a. This study combines molecular biology, biochemistry, and biophysics to provide insights into the dynamic architecture of a substrate's TM helix and its impact on non-canonical shedding. Thus, these data will provide the basis to identify further physiological substrates of non-canonical shedding in the future.
Collapse
Affiliation(s)
- Charlotte Spitz
- Biochemistry and Molecular Biology, Institute of Theoretical Medicine, Medical Faculty, University of Augsburg, Universitätsstrasse 2, 86159 Augsburg, Germany
| | - Christine Schlosser
- Biochemistry and Molecular Biology, Institute of Theoretical Medicine, Medical Faculty, University of Augsburg, Universitätsstrasse 2, 86159 Augsburg, Germany
| | - Nadja Guschtschin-Schmidt
- Karlsruhe Institute of Technology, Institute for Biological Interfaces 4, 76344 Eggenstein- Leopoldshafen, Germany and Karlsruhe Institute of Technology, Institute of Organic Chemistry, 76131 Karlsruhe, Germany
| | - Walter Stelzer
- Lehrstuhl für Chemie der Biopolymere, Technische Universität München, Weihenstephaner Berg 3, 85354 Freising, Germany
| | - Simon Menig
- Physics of Synthetic Biological Systems, Technische Universität München, Maximus-von-Imhof Forum 4, 85340 Freising, Germany
| | - Alexander Götz
- Present Address: Leibniz Supercomputing Centre, Boltzmannstr. 1, 85748 Garching, Germany
| | - Martina Haug-Kröper
- Biochemistry and Molecular Biology, Institute of Theoretical Medicine, Medical Faculty, University of Augsburg, Universitätsstrasse 2, 86159 Augsburg, Germany
| | - Christina Scharnagl
- Physics of Synthetic Biological Systems, Technische Universität München, Maximus-von-Imhof Forum 4, 85340 Freising, Germany
| | - Dieter Langosch
- Lehrstuhl für Chemie der Biopolymere, Technische Universität München, Weihenstephaner Berg 3, 85354 Freising, Germany
| | - Claudia Muhle-Goll
- Karlsruhe Institute of Technology, Institute for Biological Interfaces 4, 76344 Eggenstein- Leopoldshafen, Germany and Karlsruhe Institute of Technology, Institute of Organic Chemistry, 76131 Karlsruhe, Germany
| | - Regina Fluhrer
- Biochemistry and Molecular Biology, Institute of Theoretical Medicine, Medical Faculty, University of Augsburg, Universitätsstrasse 2, 86159 Augsburg, Germany
- DZNE – German Center for Neurodegenerative Diseases, Feodor-Lynen-Str 17, 81377 Munich, Germany
| |
Collapse
|
33
|
Gyimesi G, Hediger MA. Sequence Features of Mitochondrial Transporter Protein Families. Biomolecules 2020; 10:E1611. [PMID: 33260588 PMCID: PMC7761412 DOI: 10.3390/biom10121611] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 11/20/2020] [Accepted: 11/22/2020] [Indexed: 02/08/2023] Open
Abstract
Mitochondrial carriers facilitate the transfer of small molecules across the inner mitochondrial membrane (IMM) to support mitochondrial function and core cellular processes. In addition to the classical SLC25 (solute carrier family 25) mitochondrial carriers, the past decade has led to the discovery of additional protein families with numerous members that exhibit IMM localization and transporter-like properties. These include mitochondrial pyruvate carriers, sideroflexins, and mitochondrial cation/H+ exchangers. These transport proteins were linked to vital physiological functions and disease. Their structures and transport mechanisms are, however, still largely unknown and understudied. Protein sequence analysis per se can often pinpoint hotspots that are of functional or structural importance. In this review, we summarize current knowledge about the sequence features of mitochondrial transporters with a special focus on the newly included SLC54, SLC55 and SLC56 families of the SLC solute carrier superfamily. Taking a step further, we combine sequence conservation analysis with transmembrane segment and secondary structure prediction methods to extract residue positions and sequence motifs that likely play a role in substrate binding, binding site gating or structural stability. We hope that our review will help guide future experimental efforts by the scientific community to unravel the transport mechanisms and structures of these novel mitochondrial carriers.
Collapse
Affiliation(s)
- Gergely Gyimesi
- Membrane Transport Discovery Lab, Department of Nephrology and Hypertension, and Department of Biomedical Research, Inselspital, University of Bern, Kinderklinik, Freiburgstrasse 15, CH-3010 Bern, Switzerland;
| | | |
Collapse
|
34
|
The Janus-like role of proline metabolism in cancer. Cell Death Discov 2020; 6:104. [PMID: 33083024 PMCID: PMC7560826 DOI: 10.1038/s41420-020-00341-8] [Citation(s) in RCA: 70] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 08/18/2020] [Accepted: 09/01/2020] [Indexed: 02/06/2023] Open
Abstract
The metabolism of the non-essential amino acid L-proline is emerging as a key pathway in the metabolic rewiring that sustains cancer cells proliferation, survival and metastatic spread. Pyrroline-5-carboxylate reductase (PYCR) and proline dehydrogenase (PRODH) enzymes, which catalyze the last step in proline biosynthesis and the first step of its catabolism, respectively, have been extensively associated with the progression of several malignancies, and have been exposed as potential targets for anticancer drug development. As investigations into the links between proline metabolism and cancer accumulate, the complexity, and sometimes contradictory nature of this interaction emerge. It is clear that the role of proline metabolism enzymes in cancer depends on tumor type, with different cancers and cancer-related phenotypes displaying different dependencies on these enzymes. Unexpectedly, the outcome of rewiring proline metabolism also differs between conditions of nutrient and oxygen limitation. Here, we provide a comprehensive review of proline metabolism in cancer; we collate the experimental evidence that links proline metabolism with the different aspects of cancer progression and critically discuss the potential mechanisms involved.
Collapse
|
35
|
Raut P, Glass JB, Lieberman RL. Archaeal roots of intramembrane aspartyl protease siblings signal peptide peptidase and presenilin. Proteins 2020; 89:232-241. [PMID: 32935885 DOI: 10.1002/prot.26009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 08/27/2020] [Accepted: 09/13/2020] [Indexed: 12/21/2022]
Abstract
Signal peptides help newly synthesized proteins reach the cell membrane or be secreted. As part of a biological process key to immune response and surveillance in humans, and associated with diseases, for example, Alzheimer, remnant signal peptides and other transmembrane segments are proteolyzed by the intramembrane aspartyl protease (IAP) enzyme family. Here, we identified IAP orthologs throughout the tree of life. In addition to eukaryotes, IAPs are encoded in metabolically diverse archaea from a wide range of environments. We found three distinct clades of archaeal IAPs: (a) Euryarchaeota (eg, halophilic Halobacteriales, methanogenic Methanosarcinales and Methanomicrobiales, marine Poseidoniales, acidophilic Thermoplasmatales, hyperthermophilic Archaeoglobus spp.), (b) DPANN, and (c) Bathyarchaeota, Crenarchaeota, and Asgard. IAPs were also present in bacterial genomes from uncultivated members of Candidate Phylum Radiation, perhaps due to horizontal gene transfer from DPANN archaeal lineages. Sequence analysis of the catalytic motif YD…GXGD (where X is any amino acid) in IAPs from archaea and bacteria reveals WD in Lokiarchaeota and many residue types in the X position. Gene neighborhood analysis in halophilic archaea shows IAP genes near corrinoid transporters (btuCDF genes). In marine Euryarchaeota, a putative BtuF-like domain is found in N-terminus of the IAP gene, suggesting a role for these IAPs in metal ion cofactor or other nutrient scavenging. Interestingly, eukaryotic IAP family members appear to have evolved either from Euryarchaeota or from Asgard archaea. Taken together, our phylogenetic and bioinformatics analysis should prompt experiments to probe the biological roles of IAPs in prokaryotic secretomes.
Collapse
Affiliation(s)
- Priyam Raut
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Jennifer B Glass
- School of Biological Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA.,School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia, USA
| | - Raquel L Lieberman
- School of Chemistry & Biochemistry, Georgia Institute of Technology, Atlanta, Georgia, USA
| |
Collapse
|
36
|
Tremblay MM, Ollinger T, Houtman JCD. The membrane proximal proline-rich region and correct order of C-terminal tyrosines on the adaptor protein LAT are required for TCR-mediated signaling and downstream functions. Cell Signal 2020; 76:109790. [PMID: 32979494 DOI: 10.1016/j.cellsig.2020.109790] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 09/21/2020] [Accepted: 09/22/2020] [Indexed: 12/11/2022]
Abstract
The primary activating receptor for T cells is the T cell receptor (TCR), which is stimulated upon binding to an antigen/MHC complex. TCR activation results in the induction of regulated signaling pathways vital for T cell differentiation, cellular adhesion and cytokine release. A critical TCR-induced signaling protein is the adaptor protein LAT. Upon TCR stimulation, LAT is phosphorylated on conserved tyrosines, which facilitates the formation of multiprotein complexes needed for propagation of signaling pathways. Although the role of the conserved tyrosines in LAT-mediated signaling has been investigated, few studies have examined the role of larger regions of LAT in TCR-induced pathways. In this study, a sequence alignment of 97 mammalian LAT proteins was used to identify several "functional" domains on LAT. Using LAT mutants expressed in Jurkat E6.1 cells, we observed that the membrane proximal, proline-rich region of LAT and the correct order of domains containing conserved tyrosines are necessary for optimal TCR-mediated early signaling, cytokine production, and cellular adhesion. Together, these data show that LAT contains distinct regions whose presence and correct order are required for the propagation of TCR-mediated signaling pathways.
Collapse
Affiliation(s)
- Mikaela M Tremblay
- Department of Microbiology and Immunology, Carver College of Medicine, University of Iowa, USA
| | - Tomye Ollinger
- Department of Microbiology and Immunology, Carver College of Medicine, University of Iowa, USA
| | - Jon C D Houtman
- Department of Microbiology and Immunology, Carver College of Medicine, University of Iowa, USA.
| |
Collapse
|
37
|
Doll J, Hofrichter MAH, Bahena P, Heihoff A, Segebarth D, Müller T, Dittrich M, Haaf T, Vona B. A novel missense variant in MYO3A is associated with autosomal dominant high-frequency hearing loss in a German family. Mol Genet Genomic Med 2020; 8:e1343. [PMID: 32519820 PMCID: PMC7434730 DOI: 10.1002/mgg3.1343] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 05/16/2020] [Accepted: 05/19/2020] [Indexed: 12/30/2022] Open
Abstract
Background MYO3A, encoding the myosin IIIA protein, is associated with autosomal recessive and autosomal dominant nonsyndromic hearing loss. To date, only two missense variants located in the motor‐head domain of MYO3A have been described in autosomal dominant families with progressive, mild‐to‐profound sensorineural hearing loss. These variants alter the ATPase activity of myosin IIIA. Methods Exome sequencing of a proband from a three‐generation German family with prelingual, moderate‐to‐profound, high‐frequency hearing loss was performed. Segregation analysis confirmed a dominant inheritance pattern. Regression analysis of mean hearing level thresholds per individual and ear was performed at high‐, mid‐, and low‐frequencies. Results A novel heterozygous missense variant c.716T>C, p.(Leu239Pro) in the kinase domain of MYO3A was identified that is predicted in silico as disease causing. High‐frequency, progressive hearing loss was identified. Conclusion Correlation analysis of pure‐tone hearing thresholds revealed progressive hearing loss, especially in the high‐frequencies. In the present study, we report the first dominant likely pathogenic variant in MYO3A in a European family and further support MYO3A as an autosomal dominant hearing loss gene.
Collapse
Affiliation(s)
- Julia Doll
- Institute of Human Genetics, Julius Maximilians University, Würzburg, Germany
| | | | - Paulina Bahena
- Institute of Human Genetics, Julius Maximilians University, Würzburg, Germany
| | | | - Dennis Segebarth
- Institute of Clinical Neurobiology, University Hospital Würzburg, Würzburg, Germany
| | - Tobias Müller
- Institute of Bioinformatics, Julius Maximilians University, Würzburg, Germany
| | - Marcus Dittrich
- Institute of Human Genetics, Julius Maximilians University, Würzburg, Germany.,Institute of Bioinformatics, Julius Maximilians University, Würzburg, Germany
| | - Thomas Haaf
- Institute of Human Genetics, Julius Maximilians University, Würzburg, Germany
| | - Barbara Vona
- Institute of Human Genetics, Julius Maximilians University, Würzburg, Germany.,Tübingen Hearing Research Centre, Department of Otolaryngology - Head and Neck Surgery, Eberhard Karls University, Tübingen, Germany
| |
Collapse
|
38
|
Replacing the eleven native tryptophans by directed evolution produces an active P-glycoprotein with site-specific, non-conservative substitutions. Sci Rep 2020; 10:3224. [PMID: 32081894 PMCID: PMC7035247 DOI: 10.1038/s41598-020-59802-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 01/28/2020] [Indexed: 11/09/2022] Open
Abstract
P-glycoprotein (Pgp) pumps an array of hydrophobic compounds out of cells, and has major roles in drug pharmacokinetics and cancer multidrug resistance. Yet, polyspecific drug binding and ATP hydrolysis-driven drug export in Pgp are poorly understood. Fluorescence spectroscopy using tryptophans (Trp) inserted at strategic positions is an important tool to study ligand binding. In Pgp, this method will require removal of 11 endogenous Trps, including highly conserved Trps that may be important for function, protein-lipid interactions, and/or protein stability. Here, we developed a directed evolutionary approach to first replace all eight transmembrane Trps and select for transport-active mutants in Saccharomyces cerevisiae. Surprisingly, many Trp positions contained non-conservative substitutions that supported in vivo activity, and were preferred over aromatic amino acids. The most active construct, W(3Cyto), served for directed evolution of the three cytoplasmic Trps, where two positions revealed strong functional bias towards tyrosine. W(3Cyto) and Trp-less Pgp retained wild-type-like protein expression, localization and transport function, and purified proteins retained drug stimulation of ATP hydrolysis and drug binding affinities. The data indicate preferred Trp substitutions specific to the local context, often dictated by protein structural requirements and/or membrane lipid interactions, and these new insights will offer guidance for membrane protein engineering.
Collapse
|
39
|
Isawi IH, Morales P, Sotudeh N, Hurst DP, Lynch DL, Reggio PH. GPR6 Structural Insights: Homology Model Construction and Docking Studies. Molecules 2020; 25:molecules25030725. [PMID: 32046081 PMCID: PMC7037797 DOI: 10.3390/molecules25030725] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 02/01/2020] [Accepted: 02/04/2020] [Indexed: 01/14/2023] Open
Abstract
GPR6 is an orphan G protein-coupled receptor that has been associated with the cannabinoid family because of its recognition of a sub-set of cannabinoid ligands. The high abundance of GPR6 in the central nervous system, along with high constitutive activity and a link to several neurodegenerative diseases make GPR6 a promising biological target. In fact, diverse research groups have demonstrated that GPR6 represents a possible target for the treatment of neurodegenerative disorders such as Parkinson's disease, Alzheimer's disease, and Huntington's disease. Several patents have claimed the use of a wide range of pyrazine derivatives as GPR6 inverse agonists for the treatment of Parkinson's disease symptoms and other dyskinesia syndromes. However, the full pharmacological importance of GPR6 has not yet been fully explored due to the lack of high potency, readily available ligands targeting GPR6. The long-term goal of the present study is to develop such ligands. In this paper, we describe our initial steps towards this goal. A human GPR6 homology model was constructed using a suite of computational techniques. This model permitted the identification of unique GPR6 structural features and the exploration of the GPR6 binding crevice. A subset of patented pyrazine analogs were docked in the resultant GPR6 inactive state model to validate the model, rationalize the structure-activity relationships from the reported patents and identify the key residues in the binding crevice for ligand recognition. We will take this structural knowledge into the next phase of GPR6 project, in which scaffold hopping will be used to design new GPR6 ligands.
Collapse
Affiliation(s)
- Israa H. Isawi
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, Greensboro, NC 27412, USA; (I.H.I.); (D.P.H.); (D.L.L.)
| | - Paula Morales
- Instituto de Química Medica (IQM-CSIC), C/Juan de la Cierva 3, 28006 Madrid, Spain;
| | - Noori Sotudeh
- Department of Physiology and Biophysics, The State University of New York at Buffalo, Buffalo, NY 14260, USA;
| | - Dow P. Hurst
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, Greensboro, NC 27412, USA; (I.H.I.); (D.P.H.); (D.L.L.)
| | - Diane L. Lynch
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, Greensboro, NC 27412, USA; (I.H.I.); (D.P.H.); (D.L.L.)
| | - Patricia H. Reggio
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, Greensboro, NC 27412, USA; (I.H.I.); (D.P.H.); (D.L.L.)
- Correspondence:
| |
Collapse
|
40
|
Transmembrane Prolines Mediate Signal Sensing and Decoding in Bacillus subtilis DesK Histidine Kinase. mBio 2019; 10:mBio.02564-19. [PMID: 31772055 PMCID: PMC6879721 DOI: 10.1128/mbio.02564-19] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Signal sensing and transduction is an essential biological process for cell adaptation and survival. Histidine kinases (HK) are the sensory proteins of two-component systems that control many bacterial responses to different stimuli, like environmental changes. Here, we focused on the HK DesK from Bacillus subtilis, a paradigmatic example of a transmembrane thermosensor suited to remodel membrane fluidity when the temperature drops below 30°C. DesK provides a tractable system for investigating the mechanism of transmembrane signaling, one of the majors interrogates in biology to date. Our studies demonstrate that transmembrane proline residues modulate the conformational switch of a 2-helix coiled-coil (2-HCC) structural motif that controls input-output in a variety of HK. Our results highlight the relevance of proline residues within sensor domains and could inspire investigations of their role in different signaling proteins. Environmental awareness is an essential attribute of all organisms. The homeoviscous adaptation system of Bacillus subtilis provides a powerful experimental model for the investigation of stimulus detection and signaling mechanisms at the molecular level. These bacteria sense the order of membrane lipids with the transmembrane (TM) protein DesK, which has an N-terminal sensor domain and an intracellular catalytic effector domain. DesK exhibits autokinase activity as well as phosphotransferase and phosphatase activities toward a cognate response regulator, DesR, that controls the expression of an enzyme that remodels membrane fluidity when the temperature drops below ∼30°C. Membrane fluidity signals are transmitted from the DesK sensor domain to the effector domain via rotational movements of a connecting 2-helix coiled coil (2-HCC). Previous molecular dynamic simulations suggested important roles for TM prolines in transducing the initial signals of membrane fluidity status to the 2-HCC. Here, we report that individual replacement of prolines in DesKs TM1 and TM5 helices by alanine (DesKPA) locked DesK in a phosphatase-ON state, abrogating membrane fluidity responses. An unbiased mutagenic screen identified the L174P replacement in the internal side of the repeated heptad of the 2-HCC structure that alleviated the signaling defects of every transmembrane DesKPA substitution. Moreover, substitutions by proline in other internal positions of the 2-HCC reestablished the kinase-ON state of the DesKPA mutants. These results imply that TM prolines are essential for finely tuned signal generation by the N-terminal sensor helices, facilitating a conformational control by the metastable 2-HCC domain of the DesK signaling state.
Collapse
|
41
|
Functional characterization of the type I toxin Lpt from Lactobacillus rhamnosus by fluorescence and atomic force microscopy. Sci Rep 2019; 9:15208. [PMID: 31645607 PMCID: PMC6811638 DOI: 10.1038/s41598-019-51523-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 09/30/2019] [Indexed: 01/22/2023] Open
Abstract
Lpt is a 29 amino acid long type I toxin identified in the plasmid DNA of wild Lactobacillus rhamnosus strains isolated from food. We previously reported that transcription of the encoding gene was upregulated under nutritional starvation conditions mimicking cheese ripening environment. The heterologous expression of the Lpt peptide in E. coli resulted in cell growth inhibition, nucleoid condensation and compromised integrity of the cell membrane. Fusion of the Lpt peptide with the fluorescent protein mCherry allowed to visualize the accumulation of the peptide into the membrane, while mutagenesis experiments showed that either the insertion of a negatively charged amino acid into the hydrophobic α-helix or deletion of the hydrophilic C-terminal region, leads to a non-toxic peptide. AFM imaging of Lpt expressing E. coli cells has revealed the presence of surface defects that are compatible with the loss of portions of the outer membrane bilayer. This observation provides support for the so-called “carpet” model, by which the Lpt peptide is supposed to destabilize the phospholipid packing through a detergent-like mechanism leading to the removal of small patches of bilayer through micellization.
Collapse
|
42
|
Zhukovsky MA, Filograna A, Luini A, Corda D, Valente C. The Structure and Function of Acylglycerophosphate Acyltransferase 4/ Lysophosphatidic Acid Acyltransferase Delta (AGPAT4/LPAATδ). Front Cell Dev Biol 2019; 7:147. [PMID: 31428612 PMCID: PMC6688108 DOI: 10.3389/fcell.2019.00147] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 07/16/2019] [Indexed: 12/27/2022] Open
Abstract
Lipid-modifying enzymes serve crucial roles in cellular processes such as signal transduction (producing lipid-derived second messengers), intracellular membrane transport (facilitating membrane remodeling needed for membrane fusion/fission), and protein clustering (organizing lipid domains as anchoring platforms). The lipid products crucial in these processes can derive from different metabolic pathways, thus it is essential to know the localization, substrate specificity, deriving products (and their function) of all lipid-modifying enzymes. Here we discuss an emerging family of these enzymes, the lysophosphatidic acid acyltransferases (LPAATs), also known as acylglycerophosphate acyltransferases (AGPATs), that produce phosphatidic acid (PA) having as substrates lysophosphatidic acid (LPA) and acyl-CoA. Eleven LPAAT/AGPAT enzymes have been identified in mice and humans based on sequence homologies, and their localization, specific substrates and functions explored. We focus on one member of the family, LPAATδ, a protein expressed mainly in brain and in muscle (though to a lesser extent in other tissues); while at the cellular level it is localized at the trans-Golgi network membranes and at the mitochondrial outer membranes. LPAATδ is a physiologically essential enzyme since mice knocked-out for Lpaatδ show severe dysfunctions including cognitive impairment, impaired force contractility and altered white adipose tissue. The LPAATδ physiological roles are related to the formation of its product PA. PA is a multifunctional lipid involved in cell signaling as well as in membrane remodeling. In particular, the LPAATδ-catalyzed conversion of LPA (inverted-cone-shaped lipid) to PA (cone-shaped lipid) is considered a mechanism of deformation of the bilayer that favors membrane fission. Indeed, LPAATδ is an essential component of the fission-inducing machinery driven by the protein BARS. In this process, a protein-tripartite complex (BARS/14-3-3γ/phosphoinositide kinase PI4KIIIβ) is recruited at the trans-Golgi network, at the sites where membrane fission is to occur; there, LPAATδ directly interacts with BARS and is activated by BARS. The resulting formation of PA is essential for membrane fission occurring at those spots. Also in mitochondria PA formation has been related to fusion/fission events. Since PA is formed by various enzymatic pathways in different cell compartments, the BARS-LPAATδ interaction indicates the relevance of lipid-modifying enzymes acting exactly where their products are needed (i.e., PA at the Golgi membranes).
Collapse
Affiliation(s)
- Mikhail A Zhukovsky
- Institute of Biochemistry and Cell Biology and Institute of Protein Biochemistry, National Research Council, Naples, Italy
| | - Angela Filograna
- Institute of Biochemistry and Cell Biology and Institute of Protein Biochemistry, National Research Council, Naples, Italy
| | - Alberto Luini
- Institute of Biochemistry and Cell Biology and Institute of Protein Biochemistry, National Research Council, Naples, Italy
| | - Daniela Corda
- Institute of Biochemistry and Cell Biology and Institute of Protein Biochemistry, National Research Council, Naples, Italy
| | - Carmen Valente
- Institute of Biochemistry and Cell Biology and Institute of Protein Biochemistry, National Research Council, Naples, Italy
| |
Collapse
|
43
|
Mayol E, Campillo M, Cordomí A, Olivella M. Inter-residue interactions in alpha-helical transmembrane proteins. Bioinformatics 2019; 35:2578-2584. [PMID: 30566615 DOI: 10.1093/bioinformatics/bty978] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Revised: 10/19/2018] [Accepted: 12/17/2018] [Indexed: 01/23/2023] Open
Abstract
MOTIVATION The number of available membrane protein structures has markedly increased in the last years and, in parallel, the reliability of the methods to detect transmembrane (TM) segments. In the present report, we characterized inter-residue interactions in α-helical membrane proteins using a dataset of 3462 TM helices from 430 proteins. This is by far the largest analysis published to date. RESULTS Our analysis of residue-residue interactions in TM segments of membrane proteins shows that almost all interactions involve aliphatic residues and Phe. There is lack of polar-polar, polar-charged and charged-charged interactions except for those between Thr or Ser sidechains and the backbone carbonyl of aliphatic and Phe residues. The results are discussed in the context of the preferences of amino acids to be in the protein core or exposed to the lipid bilayer and to occupy specific positions along the TM segment. Comparison to datasets of β-barrel membrane proteins and of α-helical globular proteins unveils the specific patterns of interactions and residue composition characteristic of α-helical membrane proteins that are the clue to understanding their structure. AVAILABILITY AND IMPLEMENTATION Results data and datasets used are available at http://lmc.uab.cat/TMalphaDB/interactions.php. SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
Collapse
Affiliation(s)
- Eduardo Mayol
- Laboratori de Medicina Computacional, Unitat de Bioestadística, Facultat de Medicina, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Mercedes Campillo
- Laboratori de Medicina Computacional, Unitat de Bioestadística, Facultat de Medicina, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Arnau Cordomí
- Laboratori de Medicina Computacional, Unitat de Bioestadística, Facultat de Medicina, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Mireia Olivella
- Bioinformatics Area, School of International Studies, ESCI-UPF, Barcelona, Spain.,Bioinformatics and Medical Statistics Group, U Science Tech, Central University of Catalonia, Vic, Barcelona, Spain
| |
Collapse
|
44
|
Guerriero CJ, Gomez YK, Daskivich GJ, Reutter KR, Augustine AA, Weiberth KF, Nakatsukasa K, Grabe M, Brodsky JL. Harmonizing Experimental Data with Modeling to Predict Membrane Protein Insertion in Yeast. Biophys J 2019; 117:668-678. [PMID: 31399214 DOI: 10.1016/j.bpj.2019.07.013] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 06/26/2019] [Accepted: 07/08/2019] [Indexed: 02/06/2023] Open
Abstract
Membrane proteins must adopt their proper topologies within biological membranes, but achieving the correct topology is compromised by the presence of marginally hydrophobic transmembrane helices (TMHs). In this study, we report on a new model membrane protein in yeast that harbors two TMHs fused to an unstable nucleotide-binding domain. Because the second helix (TMH2) in this reporter has an unfavorable predicted free energy of insertion, we employed established methods to generate variants that alter TMH2 insertion free energy. We first found that altering TMH2 did not significantly affect the extent of protein degradation by the cellular quality control machinery. Next, we correlated predicted insertion free energies from a knowledge-based energy scale with the measured apparent free energies of TMH2 insertion. Although the predicted and apparent insertion energies showed a similar trend, the predicted free-energy changes spanned an unanticipated narrow range. By instead using a physics-based model, we obtained a broader range of free energies that agreed considerably better with the magnitude of the experimentally derived values. Nevertheless, some variants still inserted better in yeast than predicted from energy-based scales. Therefore, molecular dynamics simulations were performed and indicated that the corresponding mutations induced conformational changes within TMH2, which altered the number of stabilizing hydrogen bonds. Together, our results offer insight into the ability of the cellular quality control machinery to recognize conformationally distinct misfolded topomers, provide a model to assess TMH insertion in vivo, and indicate that TMH insertion energy scales may be limited depending on the specific protein and the mutation present.
Collapse
Affiliation(s)
| | - Yessica K Gomez
- Cardiovascular Research Institute, Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California
| | - Grant J Daskivich
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Karl-Richard Reutter
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Andrew A Augustine
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Kurt F Weiberth
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania
| | - Kunio Nakatsukasa
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania; Division of Biological Science, Graduate School of Natural Sciences, Nagoya City University, Nagoya, Aichi, Japan
| | - Michael Grabe
- Cardiovascular Research Institute, Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, California
| | - Jeffrey L Brodsky
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, Pennsylvania
| |
Collapse
|
45
|
Oestringer BP, Bolivar JH, Claridge JK, Almanea L, Chipot C, Dehez F, Holzmann N, Schnell JR, Zitzmann N. Hepatitis C virus sequence divergence preserves p7 viroporin structural and dynamic features. Sci Rep 2019; 9:8383. [PMID: 31182749 PMCID: PMC6557816 DOI: 10.1038/s41598-019-44413-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Accepted: 05/10/2019] [Indexed: 12/31/2022] Open
Abstract
The hepatitis C virus (HCV) viroporin p7 oligomerizes to form ion channels, which are required for the assembly and secretion of infectious viruses. The 63-amino acid p7 monomer has two putative transmembrane domains connected by a cytosolic loop, and has both N- and C- termini exposed to the endoplasmic reticulum (ER) lumen. NMR studies have indicated differences between p7 structures of distantly related HCV genotypes. A critical question is whether these differences arise from the high sequence variation between the different isolates and if so, how the divergent structures can support similar biological functions. Here, we present a side-by-side characterization of p7 derived from genotype 1b (isolate J4) in the detergent 6-cyclohexyl-1-hexylphosphocholine (Cyclofos-6) and p7 derived from genotype 5a (isolate EUH1480) in n-dodecylphosphocholine (DPC). The 5a isolate p7 in conditions previously associated with a disputed oligomeric form exhibits secondary structure, dynamics, and solvent accessibility broadly like those of the monomeric 1b isolate p7. The largest differences occur at the start of the second transmembrane domain, which is destabilized in the 5a isolate. The results show a broad consensus among the p7 variants that have been studied under a range of different conditions and indicate that distantly related HCVs preserve key features of structure and dynamics.
Collapse
Affiliation(s)
- Benjamin P Oestringer
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, United Kingdom.,Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, United Kingdom.,Immunocore Limited, 101 Park Drive, Milton Park, Abingdon, Oxon, OX14 4RY, United Kingdom
| | - Juan H Bolivar
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, United Kingdom
| | - Jolyon K Claridge
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, United Kingdom.,Structural Biology Brussels, Vrije Universiteit Brussel, Pleinlaan 2, 1050, Brussels, Belgium.,Structural and Molecular Microbiology, Structural Biology Research Center, VIB, Pleinlaan 2, 1050, Brussels, Belgium
| | - Latifah Almanea
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, United Kingdom
| | - Chris Chipot
- Laboratoire International Associé CNRS-University of Illinois at Urbana Champaign, Université de Lorraine, BP 70239, 54506, Vandœuvre-lès-Nancy, France.,Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street, Urbana, Illinois, 61801, United States
| | - François Dehez
- Laboratoire International Associé CNRS-University of Illinois at Urbana Champaign, Université de Lorraine, BP 70239, 54506, Vandœuvre-lès-Nancy, France
| | - Nicole Holzmann
- Laboratoire International Associé CNRS-University of Illinois at Urbana Champaign, Université de Lorraine, BP 70239, 54506, Vandœuvre-lès-Nancy, France
| | - Jason R Schnell
- Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, United Kingdom.
| | - Nicole Zitzmann
- Oxford Glycobiology Institute, Department of Biochemistry, University of Oxford, South Parks Road, Oxford, OX1 3QU, United Kingdom.
| |
Collapse
|
46
|
Inda ME, Vazquez DB, Fernández A, Cybulski LE. Reverse Engineering of a Thermosensing Regulator Switch. J Mol Biol 2019; 431:1016-1024. [PMID: 30738600 DOI: 10.1016/j.jmb.2019.01.025] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2018] [Revised: 01/08/2019] [Accepted: 01/09/2019] [Indexed: 01/29/2023]
Abstract
To address the mechanism of thermosensing and its implications for molecular engineering, we previously deconstructed the functional components of the bacterial thermosensor DesK, a histidine kinase with a five-span transmembrane domain that detects temperature changes. The system was first simplified by building a sensor that consists of a single chimerical transmembrane segment that retained full sensing capacity. Genetic and biophysical analysis of this minimal sensor enabled the identification of three modular components named determinants of thermodetection (DOTs). Here we combine and tune the DOTs to determine their contribution to activity. A transmembrane zipper represents the master DOT that drives a reversible and activating dimerization through the formation of hydrogen bonds. Our findings provide the mechanism and insights to construct a synthetic transmembrane helix based on a poly-valine scaffold that harbors the DOTs and regulates the activity. The construct constitutes a modular switch that may be exploited in biotechnology and genetic circuitry.
Collapse
Affiliation(s)
- María Eugenia Inda
- Departamento de Microbiología, Facultad de Ciencias Bioquímicas y Farmacéuticas, Suipacha 531, Universidad Nacional de Rosario, Argentine National Research Council (CONICET), Rosario, Argentina
| | - Daniela B Vazquez
- Departamento de Microbiología, Facultad de Ciencias Bioquímicas y Farmacéuticas, Suipacha 531, Universidad Nacional de Rosario, Argentine National Research Council (CONICET), Rosario, Argentina
| | - Ariel Fernández
- Argentine Institute of Mathematics (IAM), Buenos Aires; Chemistry Institute - INQUISUR (UNS), Bahia Blanca, National Research Council - (CONICET), Argentina
| | - Larisa E Cybulski
- Departamento de Microbiología, Facultad de Ciencias Bioquímicas y Farmacéuticas, Suipacha 531, Universidad Nacional de Rosario, Argentine National Research Council (CONICET), Rosario, Argentina.
| |
Collapse
|
47
|
Abstract
Melittin is an extensively studied, 26-residue toxic peptide from honey bee venom. Because of its versatility in adopting a variety of secondary (helix or coil) and quaternary (monomer or tetramer) structures in various environments, melittin has been the focus of numerous investigations as a model peptide in protein folding studies as well as in studies involving binding to proteins, lipids, and polysaccharides. A significant body of evidence supports the view that melittin binds to these macromolecules in a predominantly helical conformation, but detailed structural knowledge of this conformation is lacking. In this report, we present nuclear magnetic resonance (NMR)-based structural insights into the helix formation of recombinant melittin in the presence of trifluoroethanol (TFE): a known secondary structure inducer in peptides. These studies were performed at neutral pH, with micromolar amounts of the peptide. Using nuclear Overhauser effect (NOE)-derived distance restraints from three-dimensional NMR spectra, we determined the atomic resolution solution NMR structure of recombinant melittin bearing a TFE-stabilized helix. To circumvent the complications with structure determination of small peptides with high conformational flexibility, we developed a workflow for enhancing proton NOEs by increasing the viscosity of the medium. In the TFE-containing medium, recombinant monomeric melittin forms a long, continuous helical structure, which consists of the N- and C-terminal α-helices and the noncanonical 310-helix in the middle. The noncanonical 310-helix is missing in the previously solved X-ray structure of tetrameric melittin and the NMR structure of melittin in methanol. Melittin's structure in TFE-containing medium provides insights into melittin's conformational transitions, which are relevant to the peptide's interactions with its biological targets.
Collapse
Affiliation(s)
- Lisa S Ramirez
- Department of Chemistry , State University of New York at Albany , Albany , New York 12222 , United States
| | - Jayanti Pande
- Department of Chemistry , State University of New York at Albany , Albany , New York 12222 , United States
| | - Alexander Shekhtman
- Department of Chemistry , State University of New York at Albany , Albany , New York 12222 , United States
| |
Collapse
|
48
|
New Binding Sites, New Opportunities for GPCR Drug Discovery. Trends Biochem Sci 2019; 44:312-330. [PMID: 30612897 DOI: 10.1016/j.tibs.2018.11.011] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2018] [Revised: 08/11/2018] [Accepted: 11/27/2018] [Indexed: 12/29/2022]
Abstract
Many central biological events rely on protein-ligand interactions. The identification and characterization of protein-binding sites for ligands are crucial for the understanding of functions of both endogenous ligands and synthetic drug molecules. G protein-coupled receptors (GPCRs) typically detect extracellular signal molecules on the cell surface and transfer these chemical signals across the membrane, inducing downstream cellular responses via G proteins or β-arrestin. GPCRs mediate many central physiological processes, making them important targets for modern drug discovery. Here, we focus on the most recent breakthroughs in finding new binding sites and binding modes of GPCRs and their potentials for the development of new medicines.
Collapse
|
49
|
A multicomponent toxin from Bacillus cereus incites inflammation and shapes host outcome via the NLRP3 inflammasome. Nat Microbiol 2018; 4:362-374. [PMID: 30531979 DOI: 10.1038/s41564-018-0318-0] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2018] [Accepted: 11/07/2018] [Indexed: 12/25/2022]
Abstract
Host recognition of microbial components is essential in mediating an effective immune response. Cytosolic bacteria must secure entry into the host cytoplasm to facilitate replication and, in doing so, liberate microbial ligands that activate cytosolic innate immune sensors and the inflammasome. Here, we identified a multicomponent enterotoxin, haemolysin BL (HBL), that engages activation of the inflammasome. This toxin is highly conserved among the human pathogen Bacillus cereus. The three subunits of HBL bind to the cell membrane in a linear order, forming a lytic pore and inducing activation of the NLRP3 inflammasome, secretion of interleukin-1β and interleukin-18, and pyroptosis. Mechanistically, the HBL-induced pore results in the efflux of potassium and triggers the activation of the NLRP3 inflammasome. Furthermore, HBL-producing B. cereus induces rapid inflammasome-mediated mortality. Pharmacological inhibition of the NLRP3 inflammasome using MCC950 prevents B. cereus-induced lethality. Overall, our results reveal that cytosolic sensing of a toxin is central to the innate immune recognition of infection. Therapeutic modulation of this pathway enhances host protection against deadly bacterial infections.
Collapse
|
50
|
Cryo-EM reveals two distinct serotonin-bound conformations of full-length 5-HT 3A receptor. Nature 2018; 563:270-274. [PMID: 30401837 PMCID: PMC6237196 DOI: 10.1038/s41586-018-0660-7] [Citation(s) in RCA: 76] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 08/30/2018] [Indexed: 12/19/2022]
Abstract
Serotonin receptor (5-HT3AR)1, a cationic pentameric ligand-gated ion channel (pLGIC), is the clinical target for management of nausea and vomiting associated with radiation and chemotherapies2. Upon binding, serotonin induces a global conformational change encompassing the ligand-binding extracellular domain (ECD), the transmembrane domain (TMD), and the intracellular domain (ICD), the molecular details of which are unclear. Here, we present two serotonin-bound structures of the full-length 5-HT3AR in distinct conformations at 3.32 Å and 3.89 Å resolutions that reveal the mechanism underlying channel activation. When compared to Apo-5-HT3AR, serotonin-bound states underwent a large twisting motion in the ECD and TMD leading to the opening of a 165 Å long permeation pathway. Notably, this motion results in creation of lateral portals for ion permeation at the interface of the TMD and ICD. Combined with molecular dynamics simulations, these structures provide novel insights into conformational coupling across domains and functional modulation.
Collapse
|