251
|
Abstract
Recent advances suggest that the response of RNA metabolism to stress has an important role in the pathophysiology of neurodegenerative diseases, particularly amyotrophic lateral sclerosis, frontotemporal dementias and Alzheimer disease. RNA-binding proteins (RBPs) control the utilization of mRNA during stress, in part through the formation of membraneless organelles termed stress granules (SGs). These structures form through a process of liquid-liquid phase separation. Multiple biochemical pathways regulate SG biology. The major signalling pathways regulating SG formation include the mammalian target of rapamycin (mTOR)-eukaryotic translation initiation factor 4F (eIF4F) and eIF2α pathways, whereas the pathways regulating SG dispersion and removal are mediated by valosin-containing protein and the autolysosomal cascade. Post-translational modifications of RBPs also strongly contribute to the regulation of SGs. Evidence indicates that SGs are supposed to be transient structures, but the chronic stresses associated with ageing lead to chronic, persistent SGs that appear to act as a nidus for the aggregation of disease-related proteins. We suggest a model describing how intrinsic vulnerabilities within the cellular RNA metabolism might lead to the pathological aggregation of RBPs when SGs become persistent. This process might accelerate the pathophysiology of many neurodegenerative diseases and myopathies, and it suggests new targets for disease intervention.
Collapse
Affiliation(s)
- Benjamin Wolozin
- Department of Pharmacology, Boston University School of Medicine, Boston, MA, USA.
- Department of Neurology, Boston University School of Medicine, Boston, MA, USA.
| | - Pavel Ivanov
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, MA, USA
- Department of Medicine, Harvard Medical School, Boston, MA, USA
- The Broad Institute of Harvard and MIT, Cambridge, MA, USA
| |
Collapse
|
252
|
Schmidt HB, Barreau A, Rohatgi R. Phase separation-deficient TDP43 remains functional in splicing. Nat Commun 2019; 10:4890. [PMID: 31653829 PMCID: PMC6814767 DOI: 10.1038/s41467-019-12740-2] [Citation(s) in RCA: 95] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 09/27/2019] [Indexed: 12/12/2022] Open
Abstract
Intrinsically disordered regions (IDRs) are often fast-evolving protein domains of low sequence complexity that can drive phase transitions and are commonly found in many proteins associated with neurodegenerative diseases, including the RNA processing factor TDP43. Yet, how phase separation contributes to the physiological functions of TDP43 in cells remains enigmatic. Here, we combine systematic mutagenesis guided by evolutionary sequence analysis with a live-cell reporter assay of TDP43 phase dynamics to identify regularly-spaced hydrophobic motifs separated by flexible, hydrophilic segments in the IDR as a key determinant of TDP43 phase properties. This heuristic framework allows customization of the material properties of TDP43 condensates to determine effects on splicing function. Remarkably, even a mutant that fails to phase-separate at physiological concentrations can still efficiently mediate the splicing of a quantitative, single-cell splicing reporter and endogenous targets. This suggests that the ability of TDP43 to phase-separate is not essential for its splicing function.
Collapse
Affiliation(s)
| | - Ariana Barreau
- Department of Biochemistry, Stanford School of Medicine, Stanford, CA, 94305, USA
| | - Rajat Rohatgi
- Department of Biochemistry, Stanford School of Medicine, Stanford, CA, 94305, USA.
- Department of Medicine, Stanford School of Medicine, Stanford, CA, 94305, USA.
| |
Collapse
|
253
|
Damman R, Schütz S, Luo Y, Weingarth M, Sprangers R, Baldus M. Atomic-level insight into mRNA processing bodies by combining solid and solution-state NMR spectroscopy. Nat Commun 2019; 10:4536. [PMID: 31586050 PMCID: PMC6778109 DOI: 10.1038/s41467-019-12402-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 09/09/2019] [Indexed: 01/07/2023] Open
Abstract
Liquid-liquid phase separation is increasingly recognized as a process involved in cellular organization. Thus far, a detailed structural characterization of this intrinsically heterogeneous process has been challenging. Here we combine solid- and solution-state NMR spectroscopy to obtain atomic-level insights into the assembly and maturation of cytoplasmic processing bodies that contain mRNA as well as enzymes involved in mRNA degradation. In detail, we have studied the enhancer of decapping 3 (Edc3) protein that is a central hub for processing body formation in yeast. Our results reveal that Edc3 domains exhibit diverse levels of structural organization and dynamics after liquid-liquid phase separation. In addition, we find that interactions between the different Edc3 domains and between Edc3 and RNA in solution are largely preserved in the condensed protein state, allowing processing bodies to rapidly form and dissociate upon small alterations in the cellular environment.
Collapse
Affiliation(s)
- Reinier Damman
- NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands
| | - Stefan Schütz
- Department of Biophysics I, University of Regensburg, 93053, Regensburg, Germany
| | - Yanzhang Luo
- NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands
| | - Markus Weingarth
- NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands
| | - Remco Sprangers
- Department of Biophysics I, University of Regensburg, 93053, Regensburg, Germany.
| | - Marc Baldus
- NMR Spectroscopy, Bijvoet Center for Biomolecular Research, Utrecht University, Padualaan 8, 3584 CH, Utrecht, The Netherlands.
| |
Collapse
|
254
|
Vernon RM, Forman-Kay JD. First-generation predictors of biological protein phase separation. Curr Opin Struct Biol 2019; 58:88-96. [DOI: 10.1016/j.sbi.2019.05.016] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 05/17/2019] [Accepted: 05/19/2019] [Indexed: 02/06/2023]
|
255
|
Youn JY, Dyakov BJ, Zhang J, Knight JD, Vernon RM, Forman-Kay JD, Gingras AC. Properties of Stress Granule and P-Body Proteomes. Mol Cell 2019; 76:286-294. [DOI: 10.1016/j.molcel.2019.09.014] [Citation(s) in RCA: 159] [Impact Index Per Article: 31.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2019] [Revised: 09/06/2019] [Accepted: 09/09/2019] [Indexed: 01/01/2023]
|
256
|
Altered dynamics may drift pathological fibrillization in membraneless organelles. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2019; 1867:988-998. [DOI: 10.1016/j.bbapap.2019.04.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 04/08/2019] [Accepted: 04/09/2019] [Indexed: 12/12/2022]
|
257
|
Bolognesi B, Faure AJ, Seuma M, Schmiedel JM, Tartaglia GG, Lehner B. The mutational landscape of a prion-like domain. Nat Commun 2019; 10:4162. [PMID: 31519910 PMCID: PMC6744496 DOI: 10.1038/s41467-019-12101-z] [Citation(s) in RCA: 94] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Accepted: 08/15/2019] [Indexed: 12/11/2022] Open
Abstract
Insoluble protein aggregates are the hallmarks of many neurodegenerative diseases. For example, aggregates of TDP-43 occur in nearly all cases of amyotrophic lateral sclerosis (ALS). However, whether aggregates cause cellular toxicity is still not clear, even in simpler cellular systems. We reasoned that deep mutagenesis might be a powerful approach to disentangle the relationship between aggregation and toxicity. We generated >50,000 mutations in the prion-like domain (PRD) of TDP-43 and quantified their toxicity in yeast cells. Surprisingly, mutations that increase hydrophobicity and aggregation strongly decrease toxicity. In contrast, toxic variants promote the formation of dynamic liquid-like condensates. Mutations have their strongest effects in a hotspot that genetic interactions reveal to be structured in vivo, illustrating how mutagenesis can probe the in vivo structures of unstructured proteins. Our results show that aggregation of TDP-43 is not harmful but protects cells, most likely by titrating the protein away from a toxic liquid-like phase. TDP43 aggregates are a hallmark of amyotrophic lateral sclerosis. By using deep mutagenesis to measure the toxicity of more than 50,000 mutations in the prion domain of TDP43, the authors conclude that mutations that increase toxicity promote formation of liquid-like condensates, while aggregation of TDP43 is protective for the cell.
Collapse
Affiliation(s)
- Benedetta Bolognesi
- Center for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Doctor Aiguader 88, 08003, Barcelona, Spain. .,Institute of Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Barcelona, Spain.
| | - Andre J Faure
- Center for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Doctor Aiguader 88, 08003, Barcelona, Spain
| | - Mireia Seuma
- Center for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Doctor Aiguader 88, 08003, Barcelona, Spain.,Institute of Bioengineering of Catalonia (IBEC), The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - Jörn M Schmiedel
- Center for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Doctor Aiguader 88, 08003, Barcelona, Spain
| | - Gian Gaetano Tartaglia
- Center for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Doctor Aiguader 88, 08003, Barcelona, Spain.,Universitat Pompeu Fabra (UPF), Barcelona, Spain.,Institució Catalana de Recerca i Estudis Avançats (ICREA), Passeig Lluís Companys 23, 08010, Barcelona, Spain.,Department of Biology 'Charles Darwin', Sapienza University of Rome, P.le A. Moro 5, Rome, 00185, Italy
| | - Ben Lehner
- Center for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Doctor Aiguader 88, 08003, Barcelona, Spain. .,Universitat Pompeu Fabra (UPF), Barcelona, Spain. .,Institució Catalana de Recerca i Estudis Avançats (ICREA), Passeig Lluís Companys 23, 08010, Barcelona, Spain.
| |
Collapse
|
258
|
van Leeuwen W, Rabouille C. Cellular stress leads to the formation of membraneless stress assemblies in eukaryotic cells. Traffic 2019; 20:623-638. [PMID: 31152627 PMCID: PMC6771618 DOI: 10.1111/tra.12669] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 05/10/2019] [Accepted: 05/30/2019] [Indexed: 12/28/2022]
Abstract
In cells at steady state, two forms of cell compartmentalization coexist: membrane-bound organelles and phase-separated membraneless organelles that are present in both the nucleus and the cytoplasm. Strikingly, cellular stress is a strong inducer of the reversible membraneless compartments referred to as stress assemblies. Stress assemblies play key roles in survival during cell stress and in thriving of cells upon stress relief. The two best studied stress assemblies are the RNA-based processing-bodies (P-bodies) and stress granules that form in response to oxidative, endoplasmic reticulum (ER), osmotic and nutrient stress as well as many others. Interestingly, P-bodies and stress granules are heterogeneous with respect to both the pathways that lead to their formation and their protein and RNA content. Furthermore, in yeast and Drosophila, nutrient stress also leads to the formation of many other types of prosurvival cytoplasmic stress assemblies, such as metabolic enzymes foci, proteasome storage granules, EIF2B bodies, U-bodies and Sec bodies, some of which are not RNA-based. Nutrient stress leads to a drop in cytoplasmic pH, which combined with posttranslational modifications of granule contents, induces phase separation.
Collapse
Affiliation(s)
- Wessel van Leeuwen
- Hubrecht Institute of the Royal Netherlands Academy of Arts and Sciencesand University Medical Center UtrechtUtrechtthe Netherlands
| | - Catherine Rabouille
- Hubrecht Institute of the Royal Netherlands Academy of Arts and Sciencesand University Medical Center UtrechtUtrechtthe Netherlands
- Department of Biomedical Science of Cells and SystemsUniversity Medical Center GroningenGroningenthe Netherlands
| |
Collapse
|
259
|
Loughlin FE, Wilce JA. TDP-43 and FUS-structural insights into RNA recognition and self-association. Curr Opin Struct Biol 2019; 59:134-142. [PMID: 31479821 DOI: 10.1016/j.sbi.2019.07.012] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Revised: 07/29/2019] [Accepted: 07/30/2019] [Indexed: 12/13/2022]
Abstract
RNA-binding proteins TDP-43 and FUS play essential roles in pre-mRNA splicing, localization, granule formation and other aspects of RNA metabolism. Both proteins are implicated in neurodegenerative diseases amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). Despite their apparent similarities, each protein has unique structural characteristics. Here we present the current structural understanding of RNA-binding and self-association mechanisms. Both globular and intrinsically disordered domains contribute to RNA binding, each with different specificities, affinities and kinetics. Self-associating Prion-like domains in each protein form multivalent interactions and labile cross-β structures. These interactions are modulated by distinctive additional domains including a globular oligomerization domain in TDP-43 and synergistic interactions with intrinsically disordered Arginine-Glycine rich domains in FUS. These insights contribute to a better understanding of native biological functions of TDP-43 and FUS and potential molecular pathways in neurodegenerative diseases.
Collapse
Affiliation(s)
- Fionna E Loughlin
- Monash Biomedicine Discovery Institute, Department of Biochemistry & Molecular Biology, Monash University, Clayton 3800, Australia.
| | - Jacqueline A Wilce
- Monash Biomedicine Discovery Institute, Department of Biochemistry & Molecular Biology, Monash University, Clayton 3800, Australia.
| |
Collapse
|
260
|
Zhang C, Rabouille C. Membrane-Bound Meet Membraneless in Health and Disease. Cells 2019; 8:cells8091000. [PMID: 31470564 PMCID: PMC6770257 DOI: 10.3390/cells8091000] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 08/26/2019] [Accepted: 08/27/2019] [Indexed: 12/12/2022] Open
Abstract
Membraneless organelles (MLOs) are defined as cellular structures that are not sealed by a lipidic membrane and are shown to form by phase separation. They exist in both the nucleus and the cytoplasm that is also heavily populated by numerous membrane-bound organelles. Even though the name membraneless suggests that MLOs are free of membrane, both membrane and factors regulating membrane trafficking steps are emerging as important components of MLO formation and function. As a result, we name them biocondensates. In this review, we examine the relationships between biocondensates and membrane. First, inhibition of membrane trafficking in the early secretory pathway leads to the formation of biocondensates (P-bodies and Sec bodies). In the same vein, stress granules have a complex relationship with the cyto-nuclear transport machinery. Second, membrane contributes to the regulated formation of phase separation in the cells and we will present examples including clustering at the plasma membrane and at the synapse. Finally, the whole cell appears to transit from an interphase phase-separated state to a mitotic diffuse state in a DYRK3 dependent manner. This firmly establishes a crosstalk between the two types of cell organization that will need to be further explored.
Collapse
Affiliation(s)
- Chujun Zhang
- Hubrecht Institute of the Royal Netherlands Academy of Arts and Sciences, and University Medical Center Utrecht, 3584 CT Utrecht, The Netherlands
| | - Catherine Rabouille
- Hubrecht Institute of the Royal Netherlands Academy of Arts and Sciences, and University Medical Center Utrecht, 3584 CT Utrecht, The Netherlands.
- Department of Biomedical Science of Cells and Systems, University Medical Center Groningen, 9713 AV Groningen, The Netherlands.
| |
Collapse
|
261
|
Feng Z, Chen X, Wu X, Zhang M. Formation of biological condensates via phase separation: Characteristics, analytical methods, and physiological implications. J Biol Chem 2019; 294:14823-14835. [PMID: 31444270 DOI: 10.1074/jbc.rev119.007895] [Citation(s) in RCA: 128] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Liquid-liquid phase separation (LLPS) facilitates the formation of condensed biological assemblies with well-delineated physical boundaries, but without lipid membrane barriers. LLPS is increasingly recognized as a common mechanism for cells to organize and maintain different cellular compartments in addition to classical membrane-delimited organelles. Membraneless condensates have many distinct features that are not present in membrane-delimited organelles and that are likely indispensable for the viability and function of living cells. Malformation of membraneless condensates is increasingly linked to human diseases. In this review, we summarize commonly used methods to investigate various forms of LLPS occurring both in 3D aqueous solution and on 2D membrane bilayers, such as LLPS condensates arising from intrinsically disordered proteins or structured modular protein domains. We then discuss, in the context of comparisons with membrane-delimited organelles, the potential functional implications of membraneless condensate formation in cells. We close by highlighting some challenges in the field devoted to studying LLPS-mediated membraneless condensate formation.
Collapse
Affiliation(s)
- Zhe Feng
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Xudong Chen
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Xiandeng Wu
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Mingjie Zhang
- Division of Life Science, State Key Laboratory of Molecular Neuroscience, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China .,Center of Systems Biology and Human Health, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| |
Collapse
|
262
|
Stackpole EE, Akins MR, Ivshina M, Murthy AC, Fawzi NL, Fallon JR. EGFP insertional mutagenesis reveals multiple FXR2P fibrillar states with differing ribosome association in neurons. Biol Open 2019; 8:8/8/bio046383. [PMID: 31434643 PMCID: PMC6737979 DOI: 10.1242/bio.046383] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
RNA-binding proteins (RBPs) function in higher-order assemblages such as RNA granules to regulate RNA localization and translation. The Fragile X homolog FXR2P is an RBP essential for formation of neuronal Fragile X granules that associate with axonal mRNA and ribosomes in the intact brain. However, the FXR2P domains important for assemblage formation in a cellular system are unknown. Here we used an EGFP insertional mutagenesis approach to probe for FXR2P intrinsic features that influence its structural states. We tested 18 different in-frame FXR2PEGFP fusions in neurons and found that the majority did not impact assemblage formation. However, EGFP insertion within a 23 amino acid region of the low complexity (LC) domain induced FXR2PEGFP assembly into two distinct fibril states that were observed in isolation or in highly-ordered bundles. FXR2PEGFP fibrils exhibited different developmental timelines, ultrastructures and ribosome associations. Formation of both fibril types was dependent on an intact RNA-binding domain. These results suggest that restricted regions of the LC domain, together with the RNA-binding domain, may be important for FXR2P structural state organization in neurons. Summary: A mutagenesis study reveals that the higher-order structural states of the RBP FXR2P in neurons can be regulated by manipulation of the LC and RNA-binding domains.
Collapse
Affiliation(s)
- Emily E Stackpole
- Department of Neuroscience, Brown University, Providence, RI 02912, USA
| | - Michael R Akins
- Department of Biology, Drexel University, Philadelphia, PA 19104, USA
| | - Maria Ivshina
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Anastasia C Murthy
- Graduate Program in Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI 02912, USA.,Department of Molecular Pharmacology, Physiology, and Biotechnology, Brown University, Providence, RI 02912, USA
| | - Nicolas L Fawzi
- Department of Molecular Pharmacology, Physiology, and Biotechnology, Brown University, Providence, RI 02912, USA
| | - Justin R Fallon
- Department of Neuroscience, Brown University, Providence, RI 02912, USA
| |
Collapse
|
263
|
Zhou H, Luo F, Luo Z, Li D, Liu C, Li X. Programming Conventional Electron Microscopes for Solving Ultrahigh-Resolution Structures of Small and Macro-Molecules. Anal Chem 2019; 91:10996-11003. [PMID: 31334636 DOI: 10.1021/acs.analchem.9b01162] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Microcrystal electron diffraction (MicroED) is becoming a powerful tool in determining the crystal structures of biological macromolecules and small organic compounds. However, wide applications of this technique are still limited by the special requirement for radiation-tolerated movie-mode camera and the lack of automated data collection methods. Herein, we develop a stage-camera synchronization scheme to minimize the hardware requirements and enable the use of the conventional electron cryo-microscope with a single-frame CCD camera, which ensures not only the acquisition of ultrahigh-resolution diffraction data but also low cost in practice. This method renders the structure determination of both peptide and small organic compounds at ultrahigh resolution up to ∼0.60 Å with unambiguous assignment of nearly all hydrogen atoms. The present work provides a widely applicable solution for routine structure determination of MicroED and demonstrates the capability of the low-end 120 kV microscope with a CCD camera in solving ultrahigh resolution structures of both organic compounds and biological macromolecules.
Collapse
Affiliation(s)
- Heng Zhou
- Key Laboratory of Protein Sciences ( Tsinghua University ), Ministry of Education, Beijing 100084 , China.,School of Life Sciences , Tsinghua University , Beijing 100084 , China
| | - Feng Luo
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry , Chinese Academy of Sciences , Shanghai 201210 , China.,University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Zhipu Luo
- Key Laboratory of Protein Sciences ( Tsinghua University ), Ministry of Education, Beijing 100084 , China.,School of Life Sciences , Tsinghua University , Beijing 100084 , China
| | - Dan Li
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Ministry of Education , Shanghai Jiao Tong University , Shanghai 200030 , China
| | - Cong Liu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry , Chinese Academy of Sciences , Shanghai 201210 , China.,University of Chinese Academy of Sciences , Beijing 100049 , China
| | - Xueming Li
- Key Laboratory of Protein Sciences ( Tsinghua University ), Ministry of Education, Beijing 100084 , China.,School of Life Sciences , Tsinghua University , Beijing 100084 , China
| |
Collapse
|
264
|
Zatsepin NA, Li C, Colasurd P, Nannenga BL. The complementarity of serial femtosecond crystallography and MicroED for structure determination from microcrystals. Curr Opin Struct Biol 2019; 58:286-293. [PMID: 31345629 DOI: 10.1016/j.sbi.2019.06.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 06/11/2019] [Accepted: 06/11/2019] [Indexed: 11/19/2022]
Abstract
In recent years, nano and microcrystals have emerged as a valuable source of high-resolution structural information owing to the invention of serial femtosecond crystallography (SFX) with X-ray free electron lasers and microcrystal electron diffraction (MicroED) using electron cryomicroscopes. Once considered useless for structure determination, nano/microcrystals now confer significant advantages for static and time-resolved structure determination from a wide variety of difficult-to-study targets. MicroED has been used to obtain sub-Ångstrom resolution maps in which hydrogen atoms can be clearly resolved from only a few nano/microcrystals, while SFX has been used to probe protein dynamics following reaction initiation on time scales from femtoseconds to minutes. We review these two complementary techniques and their abilities for high-resolution structure determination.
Collapse
Affiliation(s)
- Nadia A Zatsepin
- Department of Physics, Arizona State University, P.O. Box 871504, Tempe, AZ 85287, USA
| | - Chufeng Li
- Department of Physics, Arizona State University, P.O. Box 871504, Tempe, AZ 85287, USA
| | - Paige Colasurd
- Chemical Engineering, School for Engineering of Matter, Transport, and Energy, Arizona State University, Tempe, AZ 85287, USA
| | - Brent L Nannenga
- Chemical Engineering, School for Engineering of Matter, Transport, and Energy, Arizona State University, Tempe, AZ 85287, USA.
| |
Collapse
|
265
|
Sequence characteristics responsible for protein‐protein interactions in the intrinsically disordered regions of caseins, amelogenins, and small heat‐shock proteins. Biopolymers 2019; 110:e23319. [DOI: 10.1002/bip.23319] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2019] [Revised: 06/11/2019] [Accepted: 06/19/2019] [Indexed: 01/01/2023]
|
266
|
Entropy and Information within Intrinsically Disordered Protein Regions. ENTROPY 2019; 21:e21070662. [PMID: 33267376 PMCID: PMC7515160 DOI: 10.3390/e21070662] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 06/27/2019] [Accepted: 07/01/2019] [Indexed: 02/06/2023]
Abstract
Bioinformatics and biophysical studies of intrinsically disordered proteins and regions (IDRs) note the high entropy at individual sequence positions and in conformations sampled in solution. This prevents application of the canonical sequence-structure-function paradigm to IDRs and motivates the development of new methods to extract information from IDR sequences. We argue that the information in IDR sequences cannot be fully revealed through positional conservation, which largely measures stable structural contacts and interaction motifs. Instead, considerations of evolutionary conservation of molecular features can reveal the full extent of information in IDRs. Experimental quantification of the large conformational entropy of IDRs is challenging but can be approximated through the extent of conformational sampling measured by a combination of NMR spectroscopy and lower-resolution structural biology techniques, which can be further interpreted with simulations. Conformational entropy and other biophysical features can be modulated by post-translational modifications that provide functional advantages to IDRs by tuning their energy landscapes and enabling a variety of functional interactions and modes of regulation. The diverse mosaic of functional states of IDRs and their conformational features within complexes demands novel metrics of information, which will reflect the complicated sequence-conformational ensemble-function relationship of IDRs.
Collapse
|
267
|
Murthy AC, Dignon GL, Kan Y, Zerze GH, Parekh SH, Mittal J, Fawzi NL. Molecular interactions underlying liquid-liquid phase separation of the FUS low-complexity domain. Nat Struct Mol Biol 2019; 26:637-648. [PMID: 31270472 PMCID: PMC6613800 DOI: 10.1038/s41594-019-0250-x] [Citation(s) in RCA: 386] [Impact Index Per Article: 77.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 05/14/2019] [Indexed: 12/12/2022]
Abstract
The low complexity domain of the RNA-binding protein FUS (FUS LC) mediates liquid-liquid phase separation (LLPS), but interactions between the repetitive SYGQ-rich sequence of FUS LC that stabilize the liquid phase are not known in detail. By combining NMR and Raman spectroscopy, mutagenesis, and molecular simulation, we demonstrate that heterogeneous interactions involving all residue types underlie LLPS of human FUS LC. We find no evidence that FUS LC adopts conformations with traditional secondary structure elements in the condensed phase, rather it maintains conformational heterogeneity. We show that hydrogen bonding, π/sp2 and hydrophobic interactions all contribute to stabilizing LLPS of FUS LC. In addition to contributions from tyrosine residues, we find that glutamine residues participate in contacts leading to LLPS of FUS LC. These results support a model in which FUS LC forms dynamic, multivalent interactions via multiple residue types and remains disordered in the densely packed liquid phase.
Collapse
Affiliation(s)
- Anastasia C Murthy
- Graduate Program in Molecular Biology, Cell Biology, and Biochemistry, Brown University, Providence, RI, USA
| | - Gregory L Dignon
- Department of Chemical and Biomolecular Engineering, Lehigh University, Bethlehem, PA, USA
| | - Yelena Kan
- LUT School of Engineering Science, LUT University, Lappeenranta, Finland.,Department of Molecular Spectroscopy, Max Planck Institute for Polymer Research, Mainz, Germany
| | - Gül H Zerze
- Department of Chemical and Biomolecular Engineering, Lehigh University, Bethlehem, PA, USA.,Department of Chemical and Biological Engineering, Princeton University, Princeton, NJ, USA
| | - Sapun H Parekh
- Department of Molecular Spectroscopy, Max Planck Institute for Polymer Research, Mainz, Germany.,Department of Biomedical Engineering, University of Texas at Austin, Austin, TX, USA
| | - Jeetain Mittal
- Department of Chemical and Biomolecular Engineering, Lehigh University, Bethlehem, PA, USA.
| | - Nicolas L Fawzi
- Department of Molecular Pharmacology, Physiology, and Biotechnology, Brown University, Providence, RI, USA.
| |
Collapse
|
268
|
Cryo-EM structures of four polymorphic TDP-43 amyloid cores. Nat Struct Mol Biol 2019; 26:619-627. [PMID: 31235914 PMCID: PMC7047951 DOI: 10.1038/s41594-019-0248-4] [Citation(s) in RCA: 166] [Impact Index Per Article: 33.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 05/10/2019] [Indexed: 12/13/2022]
Abstract
The DNA/RNA processing protein TDP-43 undergoes both functional and pathogennic aggregation. Functional TDP-43 aggregates form reversible, transient species such as nuclear bodies, stress granules, and myo-granules. Pathogenic, irreversible TDP-43 aggregates form in amyotrophic lateral sclerosis (ALS) and other neurodegenerative conditions. Here we find the features of TDP-43 fibrils that confer both reversibility and irreversibility by determining structures of two segments reported to be the pathogenic cores of human TDP-43 aggregation: SegA (residues 311–360), which forms three polymorphs, all with dagger-shaped folds; and SegB A315E (residues 286–331 containing the ALS hereditary mutation A315E), which forms R-shaped folds. Energetic analysis suggests that the dagger-shaped polymorphs represent irreversible fibril structures, whereas the SegB polymorph may participate in both reversible and irreversible fibrils. Our structures reveal the polymorphic nature of TDP-43 and suggest how the A315E mutation converts the R-shaped polymorph to an irreversible form which enhances pathology.
Collapse
|
269
|
Van Treeck B, Parker R. Emerging Roles for Intermolecular RNA-RNA Interactions in RNP Assemblies. Cell 2019; 174:791-802. [PMID: 30096311 DOI: 10.1016/j.cell.2018.07.023] [Citation(s) in RCA: 255] [Impact Index Per Article: 51.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 07/05/2018] [Accepted: 07/20/2018] [Indexed: 12/22/2022]
Abstract
Eukaryotic cells contain large assemblies of RNA and protein, referred to as ribonucleoprotein (RNP) granules, which include cytoplasmic P-bodies, stress granules, and neuronal and germinal granules, as well as nuclear paraspeckles, Cajal bodies, and RNA foci formed from repeat expansion RNAs. Recent evidence argues that intermolecular RNA-RNA interactions play a role in forming and determining the composition of certain RNP granules. We hypothesize that intermolecular RNA-RNA interactions are favored in cells yet are limited by RNA-binding proteins, helicases, and ribosomes, thereby allowing normal RNA function. An over-abundance of intermolecular RNA-RNA interactions may be toxic since perturbations that increase RNA-RNA interactions such as long repeat expansion RNAs, arginine-containing dipeptide repeat polypeptides, and sequestration or loss of abundant RNA-binding proteins can contribute to degenerative diseases.
Collapse
Affiliation(s)
- Briana Van Treeck
- Department of Biochemistry, University of Colorado, Boulder, CO 80309, USA
| | - Roy Parker
- Department of Biochemistry, University of Colorado, Boulder, CO 80309, USA; Howard Hughes Medical Institute, University of Colorado, Boulder, CO 80309, USA.
| |
Collapse
|
270
|
Gui X, Luo F, Li Y, Zhou H, Qin Z, Liu Z, Gu J, Xie M, Zhao K, Dai B, Shin WS, He J, He L, Jiang L, Zhao M, Sun B, Li X, Liu C, Li D. Structural basis for reversible amyloids of hnRNPA1 elucidates their role in stress granule assembly. Nat Commun 2019; 10:2006. [PMID: 31043593 PMCID: PMC6494871 DOI: 10.1038/s41467-019-09902-7] [Citation(s) in RCA: 133] [Impact Index Per Article: 26.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 03/29/2019] [Indexed: 11/09/2022] Open
Abstract
Subcellular membrane-less organelles consist of proteins with low complexity domains. Many of them, such as hnRNPA1, can assemble into both a polydisperse liquid phase and an ordered solid phase of amyloid fibril. The former mirrors biological granule assembly, while the latter is usually associated with neurodegenerative disease. Here, we observe a reversible amyloid formation of hnRNPA1 that synchronizes with liquid–liquid phase separation, regulates the fluidity and mobility of the liquid-like droplets, and facilitates the recruitment of hnRNPA1 into stress granules. We identify the reversible amyloid-forming cores of hnRNPA1 (named hnRACs). The atomic structures of hnRACs reveal a distinct feature of stacking Asp residues, which contributes to fibril reversibility and explains the irreversible pathological fibril formation caused by the Asp mutations identified in familial ALS. Our work characterizes the structural diversity and heterogeneity of reversible amyloid fibrils and illuminates the biological function of reversible amyloid formation in protein phase separation. Low complexity (LC) domains can drive the formation of both amyloid fibrils and protein droplets. Here, the authors identify reversible amyloid cores from the LC of hnRNPA1, based on which they elucidate the structural basis of reversible fibrillation and its interplay with hnRNPA1 droplet formation.
Collapse
Affiliation(s)
- Xinrui Gui
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 201210, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Feng Luo
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 201210, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yichen Li
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Ministry of Education, Shanghai Jiao Tong University, Shanghai, China
| | - Heng Zhou
- Beijing Advanced Innovation Center for Structural Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Zhenheng Qin
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Zhenying Liu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 201210, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jinge Gu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 201210, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Muyun Xie
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, 239 Zhang Heng Road, Pudong New District, Shanghai, 201203, China
| | - Kun Zhao
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 201210, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Bin Dai
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 201210, China
| | - Woo Shik Shin
- Department of Neurology, Molecular Biology Institute, and Brain Research Institute, UCLA, Los Angeles, CA, 90095, USA
| | - Jianhua He
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, 239 Zhang Heng Road, Pudong New District, Shanghai, 201203, China
| | - Lin He
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Ministry of Education, Shanghai Jiao Tong University, Shanghai, China
| | - Lin Jiang
- Department of Neurology, Molecular Biology Institute, and Brain Research Institute, UCLA, Los Angeles, CA, 90095, USA
| | - Minglei Zhao
- Department of Biochemistry and Molecular Biology, the University of Chicago, Chicago, IL, 60637, USA
| | - Bo Sun
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Xueming Li
- Beijing Advanced Innovation Center for Structural Biology, Tsinghua-Peking Joint Center for Life Sciences, School of Life Sciences, Tsinghua University, Beijing, China
| | - Cong Liu
- Interdisciplinary Research Center on Biology and Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 201210, China. .,University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Dan Li
- Bio-X Institutes, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Ministry of Education, Shanghai Jiao Tong University, Shanghai, China.
| |
Collapse
|
271
|
Nannenga BL, Gonen T. The cryo-EM method microcrystal electron diffraction (MicroED). Nat Methods 2019; 16:369-379. [PMID: 31040436 PMCID: PMC6568260 DOI: 10.1038/s41592-019-0395-x] [Citation(s) in RCA: 134] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Accepted: 03/25/2019] [Indexed: 01/07/2023]
Abstract
In 2013 we established a cryo-electron microscopy (cryo-EM) technique called microcrystal electron diffraction (MicroED). Since that time, data collection and analysis schemes have been fine-tuned, and structures for more than 40 different proteins, oligopeptides and organic molecules have been determined. Here we review the MicroED technique and place it in context with other structure-determination methods. We showcase example structures solved by MicroED and provide practical advice to prospective users.
Collapse
Affiliation(s)
- Brent L Nannenga
- Chemical Engineering, School for Engineering of Matter, Transport, and Energy, Arizona State University, Tempe, AZ, USA.
- Center for Applied Structural Discovery, The Biodesign Institute, Arizona State University, Tempe, AZ, USA.
| | - Tamir Gonen
- Howard Hughes Medical Institute, University of California, Los Angeles, Los Angeles, CA, USA.
- Departments of Biological Chemistry and Physiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA.
| |
Collapse
|
272
|
|
273
|
Predicted amino acid motif repeats in proteins potentially encode extensive multivalent macromolecular assemblies in the human proteome. Curr Opin Struct Biol 2019; 54:171-178. [PMID: 30978654 DOI: 10.1016/j.sbi.2019.01.026] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 01/29/2019] [Accepted: 01/31/2019] [Indexed: 01/31/2023]
Abstract
There are emerging interests in understanding higher order assemblies of biopolymers within and between cells, such as protein-protein and protein-RNA biomolecular condensates. These biomolecular condensates are thought to assemble/disassemble via multivalent interactions, including those mediated particularly by unique repeated amino acid motifs (URM). We asked how common are proteins with such URMs, their incidence and abundance, by exhaustively enumerating repeating motifs of length 3-10 in the human proteome. We found that URMs are very common and widely distributed across the human proteome. Moreover, the number of repetitions and intervals between them do not correlate with their lengths, which suggests that the number of repeats among proteins in the proteome is independent of length, contrary to the notion that short motifs are more abundant then long motifs. Finally, we describe two examples of URMs in proteins known to form higher order biopolymer assemblies: multi-PDZ domain-containing proteins and the FUS family of RNA binding proteins. For the FUS family, we predicted a known sequence 'grammar', specific motifs and interval sequence compositions that are essential to phase separation and material properties of condensates formed by this family of proteins. In PDZ domain-containing proteins we found a novel repeated motif that was surprisingly both within and between individual PDZ domains. We speculate that these motifs could be binding sites for multivalent interactions, a residual result of the mechanism by which PDZ-domain duplications occurred or that the linker sequences between PDZ domains may encode cryptic PDZ domains.
Collapse
|
274
|
Tang JD, Mura C, Lampe KJ. Stimuli-Responsive, Pentapeptide, Nanofiber Hydrogel for Tissue Engineering. J Am Chem Soc 2019; 141:4886-4899. [PMID: 30830776 DOI: 10.1021/jacs.8b13363] [Citation(s) in RCA: 167] [Impact Index Per Article: 33.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Short peptides are uniquely versatile building blocks for self-assembly. Supramolecular peptide assemblies can be used to construct functional hydrogel biomaterials-an attractive approach for neural tissue engineering. Here, we report a new class of short, five-residue peptides that form hydrogels with nanofiber structures. Using rheology and spectroscopy, we describe how sequence variations, pH, and peptide concentration alter the mechanical properties of our pentapeptide hydrogels. We find that this class of seven unmodified peptides forms robust hydrogels from 0.2-20 kPa at low weight percent (less than 3 wt %) in cell culture media and undergoes shear-thinning and rapid self-healing. The peptides self-assemble into long fibrils with sequence-dependent fibrillar morphologies. These fibrils exhibit a unique twisted ribbon shape, as visualized by transmission electron microscopy (TEM) and Cryo-EM imaging, with diameters in the low tens of nanometers and periodicities similar to amyloid fibrils. Experimental gelation behavior corroborates our molecular dynamics simulations, which demonstrate peptide assembly behavior, an increase in β-sheet content, and patterns of variation in solvent accessibility. Our rapidly assembling pentapeptides for injectable delivery (RAPID) hydrogels are syringe-injectable and support cytocompatible encapsulation of oligodendrocyte progenitor cells (OPCs), as well as their proliferation and three-dimensional process extension. Furthermore, RAPID gels protect OPCs from mechanical membrane disruption and acute loss of viability when ejected from a syringe needle, highlighting the protective capability of the hydrogel as potential cell carriers for transplantation therapies. The tunable mechanical and structural properties of these supramolecular assemblies are shown to be permissive to cell expansion and remodeling, making this hydrogel system suitable as an injectable material for cell delivery and tissue engineering applications.
Collapse
|
275
|
Zee CT, Glynn C, Gallagher-Jones M, Miao J, Santiago CG, Cascio D, Gonen T, Sawaya MR, Rodriguez JA. Homochiral and racemic MicroED structures of a peptide repeat from the ice-nucleation protein InaZ. IUCRJ 2019; 6:197-205. [PMID: 30867917 PMCID: PMC6400192 DOI: 10.1107/s2052252518017621] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 12/12/2018] [Indexed: 05/29/2023]
Abstract
The ice-nucleation protein InaZ from Pseudomonas syringae contains a large number of degenerate repeats that span more than a quarter of its sequence and include the segment GSTSTA. Ab initio structures of this repeat segment, resolved to 1.1 Å by microfocus X-ray crystallography and to 0.9 Å by the cryo-EM method MicroED, were determined from both racemic and homochiral crystals. The benefits of racemic protein crystals for structure determination by MicroED were evaluated and it was confirmed that the phase restriction introduced by crystal centrosymmetry increases the number of successful trials during the ab initio phasing of the electron diffraction data. Both homochiral and racemic GSTSTA form amyloid-like protofibrils with labile, corrugated antiparallel β-sheets that mate face to back. The racemic GSTSTA protofibril represents a new class of amyloid assembly in which all-left-handed sheets mate with their all-right-handed counterparts. This determination of racemic amyloid assemblies by MicroED reveals complex amyloid architectures and illustrates the racemic advantage in macromolecular crystallography, now with submicrometre-sized crystals.
Collapse
Affiliation(s)
- Chih-Te Zee
- Department of Chemistry and Biochemistry, UCLA-DOE Institute for Genomics and Proteomics, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Calina Glynn
- Department of Chemistry and Biochemistry, UCLA-DOE Institute for Genomics and Proteomics, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Marcus Gallagher-Jones
- Department of Chemistry and Biochemistry, UCLA-DOE Institute for Genomics and Proteomics, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Jennifer Miao
- Department of Chemistry and Biochemistry, UCLA-DOE Institute for Genomics and Proteomics, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Carlos G. Santiago
- Department of Chemistry and Biochemistry, UCLA-DOE Institute for Genomics and Proteomics, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Duilio Cascio
- Department of Biological Chemistry, UCLA-DOE Institute for Genomics and Proteomics, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Tamir Gonen
- Howard Hughes Medical Institute, Departments of Physiology and Biological Chemistry, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Michael R. Sawaya
- Department of Biological Chemistry, UCLA-DOE Institute for Genomics and Proteomics, University of California Los Angeles, Los Angeles, CA 90095, USA
| | - Jose A. Rodriguez
- Department of Chemistry and Biochemistry, UCLA-DOE Institute for Genomics and Proteomics, University of California Los Angeles, Los Angeles, CA 90095, USA
| |
Collapse
|
276
|
Abstract
Abstract
Inhibition of amyloid β peptide (Aβ) aggregation is an important goal due to the connection of this process with Alzheimer’s disease. Traditionally, inhibitors were developed with an aim to retard the overall macroscopic aggregation. However, recent advances imply that approaches based on mechanistic insights may be more powerful. In such approaches, the microscopic steps underlying the aggregation process are identified, and it is established which of these step(s) lead to neurotoxicity. Inhibitors are then derived to specifically target steps involved in toxicity. The Aβ aggregation process is composed of at minimum three microscopic steps: primary nucleation of monomers only, secondary nucleation of monomers on fibril surface, and elongation of fibrils by monomer addition. The vast majority of toxic species are generated from the secondary nucleation process: this may be a key process to inhibit in order to limit toxicity. Inhibition of primary nucleation, which delays the emergence of toxic species without affecting their total concentration, may also be effective. Inhibition of elongation may instead increase the toxicity over time. Here we briefly review findings regarding secondary nucleation of Aβ, its dominance over primary nucleation, and attempts to derive inhibitors that specifically target secondary nucleation with an aim to limit toxicity.
Collapse
Affiliation(s)
- Sara Linse
- Lund University , Department of Biochemistry and Structural Biology , P.O. Box 124 , 221 00 Lund , Sweden
- Lund University , NanoLund , Lund , Sweden
| |
Collapse
|
277
|
Gallagher-Jones M, Ophus C, Bustillo KC, Boyer DR, Panova O, Glynn C, Zee CT, Ciston J, Mancia KC, Minor AM, Rodriguez JA. Nanoscale mosaicity revealed in peptide microcrystals by scanning electron nanodiffraction. Commun Biol 2019; 2:26. [PMID: 30675524 PMCID: PMC6338664 DOI: 10.1038/s42003-018-0263-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Accepted: 12/12/2018] [Indexed: 12/15/2022] Open
Abstract
Changes in lattice structure across sub-regions of protein crystals are challenging to assess when relying on whole crystal measurements. Because of this difficulty, macromolecular structure determination from protein micro and nanocrystals requires assumptions of bulk crystallinity and domain block substructure. Here we map lattice structure across micron size areas of cryogenically preserved three-dimensional peptide crystals using a nano-focused electron beam. This approach produces diffraction from as few as 1500 molecules in a crystal, is sensitive to crystal thickness and three-dimensional lattice orientation. Real-space maps reconstructed from unsupervised classification of diffraction patterns across a crystal reveal regions of crystal order/disorder and three-dimensional lattice tilts on the sub-100nm scale. The nanoscale lattice reorientation observed in the micron-sized peptide crystal lattices studied here provides a direct view of their plasticity. Knowledge of these features facilitates an improved understanding of peptide assemblies that could aid in the determination of structures from nano- and microcrystals by single or serial crystal electron diffraction.
Collapse
Affiliation(s)
- Marcus Gallagher-Jones
- Department of Chemistry and Biochemistry, UCLA-DOE Institute for Genomics and Proteomics, University of California Los Angeles, Los Angeles, CA 90095 USA
| | - Colin Ophus
- National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
| | - Karen C. Bustillo
- National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
| | - David R. Boyer
- Department of Chemistry and Biochemistry, UCLA-DOE Institute for Genomics and Proteomics, University of California Los Angeles, Los Angeles, CA 90095 USA
| | - Ouliana Panova
- National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
- Department of Materials Science and Engineering, University of California Berkeley, Berkeley, CA 94720 USA
| | - Calina Glynn
- Department of Chemistry and Biochemistry, UCLA-DOE Institute for Genomics and Proteomics, University of California Los Angeles, Los Angeles, CA 90095 USA
| | - Chih-Te Zee
- Department of Chemistry and Biochemistry, UCLA-DOE Institute for Genomics and Proteomics, University of California Los Angeles, Los Angeles, CA 90095 USA
| | - Jim Ciston
- National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
| | - Kevin Canton Mancia
- Department of Chemistry and Biochemistry, UCLA-DOE Institute for Genomics and Proteomics, University of California Los Angeles, Los Angeles, CA 90095 USA
| | - Andrew M. Minor
- National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 USA
- Department of Materials Science and Engineering, University of California Berkeley, Berkeley, CA 94720 USA
| | - Jose A. Rodriguez
- Department of Chemistry and Biochemistry, UCLA-DOE Institute for Genomics and Proteomics, University of California Los Angeles, Los Angeles, CA 90095 USA
| |
Collapse
|
278
|
Cruz A, Verma M, Wolozin B. The Pathophysiology of Tau and Stress Granules in Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1184:359-372. [PMID: 32096049 DOI: 10.1007/978-981-32-9358-8_26] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
This chapter discusses the relationship between tau, RNA binding proteins and stress granules, which exhibit an intimate bidirectional relationship affecting the functions of both tau and the translational stress response. We describe how tau becomes hyperphosphorylated and oligomerized as part of an endogenous mechanism to promote the translational stress response through interaction with RNA binding proteins. Prior studies demonstrate that dysfunction of RNA binding proteins biology is sufficient to cause neurodegenerative diseases, such as amyotrophic lateral sclerosis and frontotemporal dementia. Emerging evidence indicates that tau-mediated neurodegeneration also occurs through a mechanism that is mediated by RNA binding proteins and the translational stress response. Discovery of the role of RNA metabolism in tauopathy opens a wide variety of novel therapeutic approaches. Multiple studies have already shown that approaches reducing the levels of selected RNA binding proteins or inhibiting the translational stress response can intervene in the pathophysiology of motoneuron diseases. Emerging studies show that reducing the levels of selected RNA binding proteins or inhibiting the translational stress response also reduces neurodegeneration in models of tauopathy and Aβ mediated degeneration. The combined impact of these studies indicate that RNA binding proteins and RNA metabolism represent a valuable new frontier for the investigation and treatment tauopathies.
Collapse
Affiliation(s)
- Anna Cruz
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA, USA
| | - Mamta Verma
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA, USA
| | - Benjamin Wolozin
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA, USA. .,Department of Neurology, Boston University School of Medicine, Boston, MA, USA. .,Program in Neuroscience, Boston University School of Medicine, Boston, MA, USA.
| |
Collapse
|
279
|
|
280
|
Hofweber M, Dormann D. Friend or foe-Post-translational modifications as regulators of phase separation and RNP granule dynamics. J Biol Chem 2018; 294:7137-7150. [PMID: 30587571 DOI: 10.1074/jbc.tm118.001189] [Citation(s) in RCA: 227] [Impact Index Per Article: 37.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Ribonucleoprotein (RNP) granules are membrane-less organelles consisting of RNA-binding proteins (RBPs) and RNA. RNA granules form through liquid-liquid phase separation (LLPS), whereby weak promiscuous interactions among RBPs and/or RNAs create a dense network of interacting macromolecules and drive the phase separation. Post-translational modifications (PTMs) of RBPs have emerged as important regulators of LLPS and RNP granule dynamics, as they can directly weaken or enhance the multivalent interactions between phase-separating macromolecules or can recruit or exclude certain macromolecules into or from condensates. Here, we review recent insights into how PTMs regulate phase separation and RNP granule dynamics, in particular arginine (Arg)-methylation and phosphorylation. We discuss how these PTMs regulate the phase behavior of prototypical RBPs and how, as "friend or foe," they might influence the assembly, disassembly, or material properties of cellular RNP granules, such as stress granules or amyloid-like condensates. We particularly highlight how PTMs control the phase separation and aggregation behavior of disease-linked RBPs. We also review how disruptions of PTMs might be involved in aberrant phase transitions and the formation of amyloid-like protein aggregates as observed in neurodegenerative diseases.
Collapse
Affiliation(s)
- Mario Hofweber
- From the BioMedical Center, Cell Biology, Ludwig-Maximilians-University Munich, Grosshaderner Strasse 9, 82152 Planegg-Martinsried.,the Graduate School of Systemic Neurosciences, Ludwig-Maximilians-University Munich, Grosshaderner Strasse 2, 82152 Planegg-Martinsried, and
| | - Dorothee Dormann
- From the BioMedical Center, Cell Biology, Ludwig-Maximilians-University Munich, Grosshaderner Strasse 9, 82152 Planegg-Martinsried, .,the Graduate School of Systemic Neurosciences, Ludwig-Maximilians-University Munich, Grosshaderner Strasse 2, 82152 Planegg-Martinsried, and.,the Munich Cluster for Systems Neurology (SyNergy), Feodor-Lynen-Strasse 17, 81377 Munich, Germany
| |
Collapse
|
281
|
Nannenga BL, Bu G, Shi D. The Evolution and the Advantages of MicroED. Front Mol Biosci 2018; 5:114. [PMID: 30619880 PMCID: PMC6299842 DOI: 10.3389/fmolb.2018.00114] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 11/26/2018] [Indexed: 11/13/2022] Open
Abstract
MicroED is a method which combines cryo-EM sample preparation and instrumentation, with electron and X-ray crystallography data analysis, and it has been employed to solve many protein crystal structures at high resolution. Initially, the main doubts of this method for structure determination were the dynamic scattering of electrons, which would cause severe inaccuracies in the measured intensities. In this paper, we will review the evolution of MicroED data collection and processing, the major differences of multiple scattering effects in protein crystals and inorganic material, and the advantages of continuous rotation data collection. Additionally, because of the periodic nature of the crystalline sample, radiation doses can be kept significantly lower than those used in single particle data collection. We review the work where this was used to assess the radiation damage of a high-energy electron beam on the protein molecules at much lower dose ranges compared to imaging.
Collapse
Affiliation(s)
- Brent L Nannenga
- School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, AZ, United States
| | - Guanhong Bu
- School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, AZ, United States
| | - Dan Shi
- Structural Biophysics Laboratory, National Frederick Laboratory for Cancer Research, National Cancer Institute, Frederick, MD, United States
| |
Collapse
|
282
|
Benson MD, Buxbaum JN, Eisenberg DS, Merlini G, Saraiva MJM, Sekijima Y, Sipe JD, Westermark P. Amyloid nomenclature 2018: recommendations by the International Society of Amyloidosis (ISA) nomenclature committee. Amyloid 2018; 25:215-219. [PMID: 30614283 DOI: 10.1080/13506129.2018.1549825] [Citation(s) in RCA: 356] [Impact Index Per Article: 59.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The nomenclature committee of the International Society of Amyloidosis (ISA) meets every second year to discuss and formulate recommendations. The conclusions from the discussion at the XVI International Symposium on Amyloidosis in Kumamoto, Japan, 25-29 March 2018 and afterwards are summarized in this Nomenclature Article. From having recommended the use of the designation "amyloid fibril" for in vivo material only, ISA's nomenclature committee now accepts its use more broadly following the international scientific literature. However, it is important always to stress the origin of the β-fibrils in order to avoid misunderstanding. Given the more broad use of the word "amyloid" several classes of amyloid fibrils may be distinguished. For the medical in vivo situation, and to be included in the amyloid nomenclature list, "amyloid" still means mainly extracellular tissue deposits of protein fibrils, recognized by specific properties, such as green-yellow birefringence after staining with Congo red. It should also be underlined that in vivo amyloid fibrils, in addition to the main protein contain associated compounds, particularly serum amyloid P-component (SAP) and proteoglycans, mainly heparan sulfate proteoglycan. With this definition there are presently 36 human amyloid proteins of which 14 appear only associated with systemic amyloidosis and 19 as localized forms. Three proteins can occur both as localized and systemic amyloidosis. Strictly intracellular aggregates are not included in this list.
Collapse
Affiliation(s)
- Merrill D Benson
- a Department of Pathology and Laboratory Medicine , Indiana University School of Medicine , Indianapolis , IN , USA
| | - Joel N Buxbaum
- b Department of Molecular Medicine , The Scripps Research Institute , La Jolla , CA , USA
| | - David S Eisenberg
- c Department of Chemistry and Biochemistry , University of California , Los Angeles , California , USA
| | - Giampaolo Merlini
- d Amyloid Research and Treatment Center , University of Pavia and IRCCS Policlinico San Matteo , Pavia , Italy
| | - Maria J M Saraiva
- e Amyloid Unit , Institute of Molecular and Cellular Biology, University of Porto , Porto , Portugal
| | - Yoshiki Sekijima
- f Department of Medicine (Neurology and Rheumatology) , Shinshu University School of Medicine , Matsumoto , Japan
| | - Jean D Sipe
- g Department of Biochemistry (Retired) , Boston University School of Medicine , Boston , MA , USA
| | - Per Westermark
- h Department of Immunology, Genetics and Pathology , Uppsala University , Uppsala , Sweden
| |
Collapse
|
283
|
Ferrolino MC, Mitrea DM, Michael JR, Kriwacki RW. Compositional adaptability in NPM1-SURF6 scaffolding networks enabled by dynamic switching of phase separation mechanisms. Nat Commun 2018; 9:5064. [PMID: 30498217 PMCID: PMC6265330 DOI: 10.1038/s41467-018-07530-1] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 11/08/2018] [Indexed: 12/18/2022] Open
Abstract
The nucleolus, the site for ribosome biogenesis contains hundreds of proteins and several types of RNA. The functions of many non-ribosomal nucleolar proteins are poorly understood, including Surfeit locus protein 6 (SURF6), an essential disordered protein with roles in ribosome biogenesis and cell proliferation. SURF6 co-localizes with Nucleophosmin (NPM1), a highly abundant protein that mediates the liquid-like features of the granular component region of the nucleolus through phase separation. Here, we show that electrostatically-driven interactions between disordered regions of NPM1 and SURF6 drive liquid-liquid phase separation. We demonstrate that co-existing heterotypic (NPM1-SURF6) and homotypic (NPM1-NPM1) scaffolding interactions within NPM1-SURF6 liquid-phase droplets dynamically and seamlessly interconvert in response to variations in molecular crowding and protein concentrations. We propose a mechanism wherein NPM1-dependent nucleolar scaffolds are modulated by non-ribosomal proteins through active rearrangements of interaction networks that can possibly contribute to the directionality of ribosomal biogenesis within the liquid-like nucleolus. The nucleolus is a membrane-less organelle and both Nucleophosmin (NPM1) and Surfeit locus protein 6 (SURF6) are abundant proteins within the nucleolus. Here the authors employ biophysical methods to study the properties of NPM1-S6N droplets and provide insights into the role of SURF6 in maintaining and modulating the liquid-like structure of the nucleolus.
Collapse
Affiliation(s)
- Mylene C Ferrolino
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Diana M Mitrea
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - J Robert Michael
- Department of Computational Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Richard W Kriwacki
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN, USA. .,Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Sciences Center, Memphis, TN, USA.
| |
Collapse
|
284
|
Bierma JC, Roskamp KW, Ledray AP, Kiss AJ, Cheng CHC, Martin RW. Controlling Liquid-Liquid Phase Separation of Cold-Adapted Crystallin Proteins from the Antarctic Toothfish. J Mol Biol 2018; 430:5151-5168. [PMID: 30414964 DOI: 10.1016/j.jmb.2018.10.023] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Revised: 10/30/2018] [Accepted: 10/31/2018] [Indexed: 12/22/2022]
Abstract
Liquid-liquid phase separation (LLPS) of proteins is important to a variety of biological processes both functional and deleterious, including the formation of membraneless organelles, molecular condensations that sequester or release molecules in response to stimuli, and the early stages of disease-related protein aggregation. In the protein-rich, crowded environment of the eye lens, LLPS manifests as cold cataract. We characterize the LLPS behavior of six structural γ-crystallins from the eye lens of the Antarctic toothfish Dissostichus mawsoni, whose intact lenses resist cold cataract in subzero waters. Phase separation of these proteins is not strongly correlated with thermal stability, aggregation propensity, or cross-species chaperone protection from heat denaturation. Instead, LLPS is driven by protein-protein interactions involving charged residues. The critical temperature of the phase transition can be tuned over a wide temperature range by selective substitution of surface residues, suggesting general principles for controlling this phenomenon, even in compactly folded proteins.
Collapse
Affiliation(s)
- Jan C Bierma
- Department of Molecular Biology & Biochemistry, University of California, Irvine, CA 92697, USA
| | - Kyle W Roskamp
- Department of Chemistry, University of California, Irvine, CA 92697, USA
| | - Aaron P Ledray
- Department of Molecular Biology & Biochemistry, University of California, Irvine, CA 92697, USA
| | - Andor J Kiss
- Center for Bioinformatics and Functional Genomics, Miami University, Oxford, OH 45056,USA.
| | - C-H Christina Cheng
- Department of Animal Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801,USA
| | - Rachel W Martin
- Department of Molecular Biology & Biochemistry, University of California, Irvine, CA 92697, USA; Department of Chemistry, University of California, Irvine, CA 92697, USA.
| |
Collapse
|
285
|
Mitrea DM, Chandra B, Ferrolino MC, Gibbs EB, Tolbert M, White MR, Kriwacki RW. Methods for Physical Characterization of Phase-Separated Bodies and Membrane-less Organelles. J Mol Biol 2018; 430:4773-4805. [PMID: 30017918 PMCID: PMC6503534 DOI: 10.1016/j.jmb.2018.07.006] [Citation(s) in RCA: 105] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 07/04/2018] [Accepted: 07/09/2018] [Indexed: 12/17/2022]
Abstract
Membrane-less organelles are cellular structures which arise through the phenomenon of phase separation. This process enables compartmentalization of specific sets of macromolecules (e.g., proteins, nucleic acids), thereby regulating cellular processes by increasing local concentration, and modulating the structure and dynamics of their constituents. Understanding the connection between structure, material properties and function of membrane-less organelles requires inter-disciplinary approaches, which address length and timescales that span several orders of magnitude (e.g., Ångstroms to micrometer, picoseconds to hours). In this review, we discuss the wide variety of methods that have been applied to characterize the morphology, rheology, structure and dynamics of membrane-less organelles and their components, in vitro and in live cells.
Collapse
Affiliation(s)
- Diana M Mitrea
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA.
| | - Bappaditya Chandra
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Mylene C Ferrolino
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Eric B Gibbs
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Michele Tolbert
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Michael R White
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - Richard W Kriwacki
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, USA; Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Sciences Center, Memphis, TN 38163, USA.
| |
Collapse
|
286
|
Tome JM, Tippens ND, Lis JT. Single-molecule nascent RNA sequencing identifies regulatory domain architecture at promoters and enhancers. Nat Genet 2018; 50:1533-1541. [PMID: 30349116 PMCID: PMC6422046 DOI: 10.1038/s41588-018-0234-5] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Accepted: 08/14/2018] [Indexed: 12/23/2022]
Abstract
Eukaryotic RNA polymerase II (Pol II) has been found at both promoters and distal enhancers, suggesting additional functions beyond mRNA production. To understand this role, we sequenced nascent RNAs at single-molecule resolution to unravel the interplay between Pol II initiation, capping and pausing genome-wide. Our analyses identify two pause classes that are associated with different RNA capping profiles. More proximal pausing is associated with less complete capping, less elongation and a more enhancer-like complement of transcription factors than later pausing. Unexpectedly, transcription start sites (TSSs) are predominantly found in constellations composed of multiple divergent pairs. TSS clusters are intimately associated with precise arrays of nucleosomes and correspond with boundaries of transcription factor binding and chromatin modification at promoters and enhancers. TSS architecture is largely unchanged during the dramatic transcriptional changes induced by heat shock. Together, our results suggest that promoter- and enhancer-associated Pol II is a regulatory nexus for integrating information across TSS ensembles.
Collapse
Affiliation(s)
- Jacob M Tome
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA.,Department of Genome Sciences, University of Washington, Seattle, WA, USA
| | - Nathaniel D Tippens
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA.,Tri-Institutional Training Program in Computational Biology and Medicine, Cornell University, Ithaca, NY, USA.,Department of Biological Statistics & Computational Biology, College of Agriculture and Life Sciences, Cornell University, Ithaca, NY, USA
| | - John T Lis
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY, USA. .,Tri-Institutional Training Program in Computational Biology and Medicine, Cornell University, Ithaca, NY, USA.
| |
Collapse
|
287
|
Diaferia C, Balasco N, Altamura D, Sibillano T, Gallo E, Roviello V, Giannini C, Morelli G, Vitagliano L, Accardo A. Assembly modes of hexaphenylalanine variants as function of the charge states of their terminal ends. SOFT MATTER 2018; 14:8219-8230. [PMID: 30265271 DOI: 10.1039/c8sm01441h] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The ability of peptides to self-assemble represents a valuable tool for the development of biomaterials of biotechnological and/or biomedical interest. Diphenylalanine homodimer (FF) and its analogues are among the most promising systems in this field. The longest Phe-based building block hitherto characterized is pentaphenylalanine (F5). We studied the aggregation propensity and the structural/morphological features of assemblies of zwitterionic hexaphenylalanine H+-F6-O- and of three variants characterized by different charged states of the terminal ends (Ac-F6-Amide, H+-F6-Amide and Ac-F6-O-). As previously observed for PEGylated hexaphenylalanine (PEG8-F6), all F6 variants show a strong tendency to form β-rich assemblies in which the structural motif is constituted by antiparallel β-strands in the cross-β framework. Extensive replica exchange molecular dynamics simulations carried out on a pairs of F6 peptides indicate that the antiparallel β-structure of the final assemblies is likely dictated by the preferred association modes of the individual chains in the very early stages of the aggregation process. Our data suggest that even very small F6 peptides are properly pre-organized and prone to the build-up of the final assembly.
Collapse
Affiliation(s)
- Carlo Diaferia
- Department of Pharmacy, Research Centre on Bioactive Peptides (CIRPeB), University of Naples "Federico II", Via Mezzocannone 16, 80134, Naples, Italy.
| | - Nicole Balasco
- Institute of Biostructures and Bioimaging (IBB), CNR, Via Mezzocannone 16, 80134, Naples, Italy
| | - Davide Altamura
- Institute of Crystallography (IC), CNR, Via Amendola 122, 70126, Bari, Italy
| | - Teresa Sibillano
- Institute of Crystallography (IC), CNR, Via Amendola 122, 70126, Bari, Italy
| | - Enrico Gallo
- Department of Pharmacy, Research Centre on Bioactive Peptides (CIRPeB), University of Naples "Federico II", Via Mezzocannone 16, 80134, Naples, Italy.
| | - Valentina Roviello
- Analytical Chemistry for the Environment and CeSMA (Advanced Metrologic Service Center), University of Naples "Federico II", Corso Nicolangelo Protopisani, 80146, Naples, Italy
| | - Cinzia Giannini
- Institute of Crystallography (IC), CNR, Via Amendola 122, 70126, Bari, Italy
| | - Giancarlo Morelli
- Department of Pharmacy, Research Centre on Bioactive Peptides (CIRPeB), University of Naples "Federico II", Via Mezzocannone 16, 80134, Naples, Italy.
| | - Luigi Vitagliano
- Institute of Biostructures and Bioimaging (IBB), CNR, Via Mezzocannone 16, 80134, Naples, Italy
| | - Antonella Accardo
- Department of Pharmacy, Research Centre on Bioactive Peptides (CIRPeB), University of Naples "Federico II", Via Mezzocannone 16, 80134, Naples, Italy.
| |
Collapse
|
288
|
Murray DT, Zhou X, Kato M, Xiang S, Tycko R, McKnight SL. Structural characterization of the D290V mutation site in hnRNPA2 low-complexity-domain polymers. Proc Natl Acad Sci U S A 2018; 115:E9782-E9791. [PMID: 30279180 PMCID: PMC6196502 DOI: 10.1073/pnas.1806174115] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Human genetic studies have given evidence of familial, disease-causing mutations in the analogous amino acid residue shared by three related RNA binding proteins causative of three neurological diseases. Alteration of aspartic acid residue 290 of hnRNPA2 to valine is believed to predispose patients to multisystem proteinopathy. Mutation of aspartic acid 262 of hnRNPA1 to either valine or asparagine has been linked to either amyotrophic lateral sclerosis or multisystem proteinopathy. Mutation of aspartic acid 378 of hnRNPDL to either asparagine or histidine has been associated with limb girdle muscular dystrophy. All three of these aspartic acid residues map to evolutionarily conserved regions of low-complexity (LC) sequence that may function in states of either intrinsic disorder or labile self-association. Here, we present a combination of solid-state NMR spectroscopy with segmental isotope labeling and electron microscopy on the LC domain of the hnRNPA2 protein. We show that, for both the wild-type protein and the aspartic acid 290-to-valine mutant, labile polymers are formed in which the LC domain associates into an in-register cross-β conformation. Aspartic acid 290 is shown to be charged at physiological pH and immobilized within the polymer core. Polymers of the aspartic acid 290-to-valine mutant are thermodynamically more stable than wild-type polymers. These observations give evidence that removal of destabilizing electrostatic interactions may be responsible for the increased propensity of the mutated LC domains to self-associate in disease-causing conformations.
Collapse
Affiliation(s)
- Dylan T Murray
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Disease, Bethesda, MD 20892
- Postdoctoral Research Associate Training Program, National Institute of General Medical Sciences, Bethesda, MD 20892
| | - Xiaoming Zhou
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Masato Kato
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Siheng Xiang
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Robert Tycko
- Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Disease, Bethesda, MD 20892;
| | - Steven L McKnight
- Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, TX 75390
| |
Collapse
|
289
|
Díaz-Caballero M, Fernández MR, Navarro S, Ventura S. Prion-based nanomaterials and their emerging applications. Prion 2018; 12:266-272. [PMID: 30196749 PMCID: PMC6277190 DOI: 10.1080/19336896.2018.1521235] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2018] [Revised: 08/22/2018] [Accepted: 08/23/2018] [Indexed: 12/12/2022] Open
Abstract
Protein misfolding and aggregation into highly ordered fibrillar structures have been traditionally associated with pathological processes. Nevertheless, nature has taken advantage of the particular properties of amyloids for functional purposes, like in the protection of organisms against environmental changing conditions. Over the last decades, these fibrillar structures have inspired the design of new nanomaterials with intriguing applications in biomedicine and nanotechnology such as tissue engineering, drug delivery, adhesive materials, biodegradable nanocomposites, nanowires or biosensors. Prion and prion-like proteins, which are considered a subclass of amyloids, are becoming ideal candidates for the design of new and tunable nanomaterials. In this review, we discuss the particular properties of this kind of proteins, and the current advances on the design of new materials based on prion sequences.
Collapse
Affiliation(s)
- Marta Díaz-Caballero
- Institut de Biotecnologia i de Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autonoma de Barcelona, Bellaterra (Barcelona), Spain
| | - Maria Rosario Fernández
- Institut de Biotecnologia i de Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autonoma de Barcelona, Bellaterra (Barcelona), Spain
| | - Susanna Navarro
- Institut de Biotecnologia i de Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autonoma de Barcelona, Bellaterra (Barcelona), Spain
| | - Salvador Ventura
- Institut de Biotecnologia i de Biomedicina and Departament de Bioquímica i Biologia Molecular, Universitat Autonoma de Barcelona, Bellaterra (Barcelona), Spain
| |
Collapse
|
290
|
Aviolat H, Nominé Y, Gioria S, Bonhoure A, Hoffmann D, Ruhlmann C, Nierengarten H, Ruffenach F, Villa P, Trottier Y, Klein FAC. SynAggreg: A Multifunctional High-Throughput Technology for Precision Study of Amyloid Aggregation and Systematic Discovery of Synergistic Inhibitor Compounds. J Mol Biol 2018; 430:5257-5279. [PMID: 30266595 DOI: 10.1016/j.jmb.2018.09.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 08/30/2018] [Accepted: 09/11/2018] [Indexed: 11/19/2022]
Abstract
Numerous proteins can coalesce into amyloid self-assemblies, which are responsible for a class of diseases called amyloidoses, but which can also fulfill important biological functions and are of great interest for biotechnology. Amyloid aggregation is a complex multi-step process, poorly prone to detailed structural studies. Therefore, small molecules interacting with amyloids are often used as tools to probe the amyloid aggregation pathway and in some cases to treat amyloidoses as they prevent pathogenic protein aggregation. Here, we report on SynAggreg, an in vitro high-throughput (HT) platform dedicated to the precision study of amyloid aggregation and the effect of modulator compounds. SynAggreg relies on an accurate bi-fluorescent amyloid-tracer readout that overcomes some limitations of existing HT methods. It allows addressing diverse aspects of aggregation modulation that are critical for pathomechanistic studies, such as the specificity of compounds toward various amyloids and their effects on aggregation kinetics, as well as the co-assembly propensity of distinct amyloids and the influence of prion-like seeding on self-assembly. Furthermore, SynAggreg is the first HT technology that integrates tailored methodology to systematically identify synergistic compound combinations-an emerging strategy to improve fatal amyloidoses by targeting multiple steps of the aggregation pathway. To this end, we apply analytical combinatorial scores to rank the inhibition efficiency of couples of compounds and to readily detect synergism. Finally, the SynAggreg platform should be suited for the characterization of a broad class of amyloids, whether of interest for drug development purposes, for fundamental research on amyloid functions, or for biotechnological applications.
Collapse
Affiliation(s)
- Hubert Aviolat
- Institute of Genetics and Molecular and Cellular Biology (IGBMC), Illkirch, France; Centre National de la Recherche Scientifique, UMR7104, Illkirch, France; Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France; University of Strasbourg, Strasbourg, France
| | - Yves Nominé
- Institute of Genetics and Molecular and Cellular Biology (IGBMC), Illkirch, France; Centre National de la Recherche Scientifique, UMR7104, Illkirch, France; Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France; University of Strasbourg, Strasbourg, France
| | - Sophie Gioria
- University of Strasbourg, Strasbourg, France; Integrative Biological Chemistry Platform of Strasbourg, Illkirch, France
| | - Anna Bonhoure
- Institute of Genetics and Molecular and Cellular Biology (IGBMC), Illkirch, France; Centre National de la Recherche Scientifique, UMR7104, Illkirch, France; Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France; University of Strasbourg, Strasbourg, France
| | - David Hoffmann
- Institute of Genetics and Molecular and Cellular Biology (IGBMC), Illkirch, France; Centre National de la Recherche Scientifique, UMR7104, Illkirch, France; Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France; University of Strasbourg, Strasbourg, France
| | - Christine Ruhlmann
- Institute of Genetics and Molecular and Cellular Biology (IGBMC), Illkirch, France; Centre National de la Recherche Scientifique, UMR7104, Illkirch, France; Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France; University of Strasbourg, Strasbourg, France
| | - Hélène Nierengarten
- University of Strasbourg, Strasbourg, France; Institut de Chimie de Strasbourg, UMR7177, Strasbourg, France
| | - Frank Ruffenach
- Institute of Genetics and Molecular and Cellular Biology (IGBMC), Illkirch, France; Centre National de la Recherche Scientifique, UMR7104, Illkirch, France; Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France; University of Strasbourg, Strasbourg, France
| | - Pascal Villa
- University of Strasbourg, Strasbourg, France; Integrative Biological Chemistry Platform of Strasbourg, Illkirch, France; Centre National de la Recherche Scientifique, UMS 3286, Illkirch, France
| | - Yvon Trottier
- Institute of Genetics and Molecular and Cellular Biology (IGBMC), Illkirch, France; Centre National de la Recherche Scientifique, UMR7104, Illkirch, France; Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France; University of Strasbourg, Strasbourg, France.
| | - Fabrice A C Klein
- Institute of Genetics and Molecular and Cellular Biology (IGBMC), Illkirch, France; Centre National de la Recherche Scientifique, UMR7104, Illkirch, France; Institut National de la Santé et de la Recherche Médicale, U1258, Illkirch, France; University of Strasbourg, Strasbourg, France.
| |
Collapse
|
291
|
Extreme amyloid polymorphism in Staphylococcus aureus virulent PSMα peptides. Nat Commun 2018; 9:3512. [PMID: 30158633 PMCID: PMC6115460 DOI: 10.1038/s41467-018-05490-0] [Citation(s) in RCA: 73] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 07/10/2018] [Indexed: 01/07/2023] Open
Abstract
Members of the Staphylococcus aureus phenol-soluble modulin (PSM) peptide family are secreted as functional amyloids that serve diverse roles in pathogenicity and may be present as full-length peptides or as naturally occurring truncations. We recently showed that the activity of PSMα3, the most toxic member, stems from the formation of cross-α fibrils, which are at variance with the cross-β fibrils linked with eukaryotic amyloid pathologies. Here, we show that PSMα1 and PSMα4, involved in biofilm structuring, form canonical cross-β amyloid fibrils wherein β-sheets tightly mate through steric zipper interfaces, conferring high stability. Contrastingly, a truncated PSMα3 has antibacterial activity, forms reversible fibrils, and reveals two polymorphic and atypical β-rich fibril architectures. These architectures are radically different from both the cross-α fibrils formed by full-length PSMα3, and from the canonical cross-β fibrils. Our results point to structural plasticity being at the basis of the functional diversity exhibited by S. aureus PSMαs.
Collapse
|
292
|
Törnquist M, Michaels TCT, Sanagavarapu K, Yang X, Meisl G, Cohen SIA, Knowles TPJ, Linse S. Secondary nucleation in amyloid formation. Chem Commun (Camb) 2018; 54:8667-8684. [PMID: 29978862 DOI: 10.1039/c8cc02204f] [Citation(s) in RCA: 278] [Impact Index Per Article: 46.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Nucleation of new peptide and protein aggregates on the surfaces of amyloid fibrils of the same peptide or protein has emerged in the past two decades as a major pathway for both the generation of molecular species responsible for cellular toxicity and for the autocatalytic proliferation of peptide and protein aggregates. A key question in current research is the molecular mechanism and driving forces governing such processes, known as secondary nucleation. In this context, the analogies with other self-assembling systems for which monomer-dependent secondary nucleation has been studied for more than a century provide a valuable source of inspiration. Here, we present a short overview of this background and then review recent results regarding secondary nucleation of amyloid-forming peptides and proteins, focusing in particular on the amyloid β peptide (Aβ) from Alzheimer's disease, with some examples regarding α-synuclein from Parkinson's disease. Monomer-dependent secondary nucleation of Aβ was discovered using a combination of kinetic experiments, global analysis, seeding experiments and selective isotope-enrichment, which pinpoint the monomer as the origin of new aggregates in a fibril-catalyzed reaction. Insights into driving forces are gained from variations of solution conditions, temperature and peptide sequence. Selective inhibition of secondary nucleation is explored as an effective means to limit oligomer production and toxicity. We also review experiments aimed at finding interaction partners of oligomers generated by secondary nucleation in an ongoing aggregation process. At the end of this feature article we bring forward outstanding questions and testable mechanistic hypotheses regarding monomer-dependent secondary nucleation in amyloid formation.
Collapse
Affiliation(s)
- Mattias Törnquist
- Lund University, Department of Biochemistry and Structural Biology, Chemical Centre, PO Box 124, SE221 00 Lund, Sweden.
| | | | | | | | | | | | | | | |
Collapse
|
293
|
Mittag T, Parker R. Multiple Modes of Protein-Protein Interactions Promote RNP Granule Assembly. J Mol Biol 2018; 430:4636-4649. [PMID: 30099026 DOI: 10.1016/j.jmb.2018.08.005] [Citation(s) in RCA: 131] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 08/01/2018] [Accepted: 08/02/2018] [Indexed: 12/21/2022]
Abstract
Eukaryotic cells are known to contain a wide variety of RNA-protein assemblies, collectively referred to as RNP granules. RNP granules form from a combination of RNA-RNA, protein-RNA, and protein-protein interactions. In addition, RNP granules are enriched in proteins with intrinsically disordered regions (IDRs), which are frequently appended to a well-folded domain of the same protein. This structural organization of RNP granule components allows for a diverse set of protein-protein interactions including traditional structured interactions between well-folded domains, interactions of short linear motifs in IDRs with the surface of well-folded domains, interactions of short motifs within IDRs that weakly interact with related motifs, and weak interactions involving at most transient ordering of IDRs and folded domains with other components. In addition, both well-folded domains and IDRs in granule components frequently interact with RNA and thereby can contribute to RNP granule assembly. We discuss the contribution of these interactions to liquid-liquid phase separation and the possible role of phase separation in the assembly of RNP granules. We expect that these principles also apply to other non-membrane bound organelles and large assemblies in the cell.
Collapse
Affiliation(s)
- Tanja Mittag
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, United States.
| | - Roy Parker
- Department of Chemistry and Biochemistry & Howard Hughes Medical Institute, University of Colorado, Boulder, CO 80303, United States.
| |
Collapse
|
294
|
Maziuk BF, Apicco DJ, Cruz AL, Jiang L, Ash PEA, da Rocha EL, Zhang C, Yu WH, Leszyk J, Abisambra JF, Li H, Wolozin B. RNA binding proteins co-localize with small tau inclusions in tauopathy. Acta Neuropathol Commun 2018; 6:71. [PMID: 30068389 PMCID: PMC6069705 DOI: 10.1186/s40478-018-0574-5] [Citation(s) in RCA: 92] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Accepted: 07/19/2018] [Indexed: 02/07/2023] Open
Abstract
The development of insoluble, intracellular neurofibrillary tangles composed of the microtubule-associated protein tau is a defining feature of tauopathies, including Alzheimer's disease (AD). Accumulating evidence suggests that tau pathology co-localizes with RNA binding proteins (RBPs) that are known markers for stress granules (SGs). Here we used proteomics to determine how the network of tau binding proteins changes with disease in the rTg4510 mouse, and then followed up with immunohistochemistry to identify RNA binding proteins that co-localize with tau pathology. The tau interactome networks revealed striking disease-related changes in interactions between tau and a multiple RBPs, and biochemical fractionation studies demonstrated that many of these proteins including hnRNPA0, EWSR1, PABP and RPL7 form insoluble aggregates as tau pathology develops. Immunohistochemical analysis of mouse and human brain tissues suggest a model of evolving pathological interaction, in which RBPs co-localize with pathological phospho-tau but occur adjacent to larger pathological tau inclusions. We suggest a model in which tau initially interacts with RBPs in small complexes, but evolves into isolated aggregated inclusions as tau pathology matures.
Collapse
Affiliation(s)
- Brandon F Maziuk
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA, USA
| | - Daniel J Apicco
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA, USA
| | - Anna Lourdes Cruz
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA, USA
| | - Lulu Jiang
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA, USA
| | - Peter E A Ash
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA, USA
| | | | | | - Wai Haung Yu
- Department of Pathology and Cell Biology, Taub Institute for Alzheimer's Disease Research, Columbia University Medical Center, New York, NY, USA
| | - John Leszyk
- University of Massachusetts Medical Center, Worcester, MA, USA
| | - Jose F Abisambra
- Sanders-Brown Center on Aging, Department of Physiology, Spinal Cord and Brain Injury Research Center, and Epilepsy Center, University of Kentucky, Lexington, KY, USA
| | - Hu Li
- Mayo Clinic, Rochester, MN, USA
| | - Benjamin Wolozin
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA, USA.
- Department of Neurology, Boston University School of Medicine, Boston, MA, USA.
- Department of Pharmacology and Neurology Program in Neuroscience, Boston University School of Medicine, 72 East Concord St., R614, Boston, MA, 02118-2526, USA.
| |
Collapse
|
295
|
Abstract
Eukaryotic cells organize their intracellular components into organelles that can be membrane-bound or membraneless. A large number of membraneless organelles, including nucleoli, Cajal bodies, P-bodies, and stress granules, exist as liquid droplets within the cell and arise from the condensation of cellular material in a process termed liquid-liquid phase separation (LLPS). Beyond a mere organizational tool, concentrating cellular components into membraneless organelles tunes biochemical reactions and improves cellular fitness during stress. In this review, we provide an overview of the molecular underpinnings of the formation and regulation of these membraneless organelles. This molecular understanding explains emergent properties of these membraneless organelles and shines new light on neurodegenerative diseases, which may originate from disturbances in LLPS and membraneless organelles.
Collapse
Affiliation(s)
- Edward Gomes
- From the Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| | - James Shorter
- From the Department of Biochemistry and Biophysics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104
| |
Collapse
|
296
|
Wang J, Choi JM, Holehouse AS, Lee HO, Zhang X, Jahnel M, Maharana S, Lemaitre R, Pozniakovsky A, Drechsel D, Poser I, Pappu RV, Alberti S, Hyman AA. A Molecular Grammar Governing the Driving Forces for Phase Separation of Prion-like RNA Binding Proteins. Cell 2018; 174:688-699.e16. [PMID: 29961577 DOI: 10.1016/j.cell.2018.06.006] [Citation(s) in RCA: 1145] [Impact Index Per Article: 190.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 03/19/2018] [Accepted: 05/31/2018] [Indexed: 12/23/2022]
Abstract
Proteins such as FUS phase separate to form liquid-like condensates that can harden into less dynamic structures. However, how these properties emerge from the collective interactions of many amino acids remains largely unknown. Here, we use extensive mutagenesis to identify a sequence-encoded molecular grammar underlying the driving forces of phase separation of proteins in the FUS family and test aspects of this grammar in cells. Phase separation is primarily governed by multivalent interactions among tyrosine residues from prion-like domains and arginine residues from RNA-binding domains, which are modulated by negatively charged residues. Glycine residues enhance the fluidity, whereas glutamine and serine residues promote hardening. We develop a model to show that the measured saturation concentrations of phase separation are inversely proportional to the product of the numbers of arginine and tyrosine residues. These results suggest it is possible to predict phase-separation properties based on amino acid sequences.
Collapse
Affiliation(s)
- Jie Wang
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
| | - Jeong-Mo Choi
- Department of Biomedical Engineering and Center for Biological Systems Engineering, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Alex S Holehouse
- Department of Biomedical Engineering and Center for Biological Systems Engineering, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Hyun O Lee
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
| | - Xiaojie Zhang
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
| | - Marcus Jahnel
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
| | - Shovamayee Maharana
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
| | - Régis Lemaitre
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
| | - Andrei Pozniakovsky
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
| | - David Drechsel
- Research Institute of Molecular Pathology, Campus-Vienna-Biocenter 1, 1030 Vienna, Austria
| | - Ina Poser
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
| | - Rohit V Pappu
- Department of Biomedical Engineering and Center for Biological Systems Engineering, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Simon Alberti
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany.
| | - Anthony A Hyman
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany.
| |
Collapse
|
297
|
Franzmann TM, Alberti S. Prion-like low-complexity sequences: Key regulators of protein solubility and phase behavior. J Biol Chem 2018; 294:7128-7136. [PMID: 29921587 DOI: 10.1074/jbc.tm118.001190] [Citation(s) in RCA: 152] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Many proteins, such as RNA-binding proteins, have complex folding landscapes. How cells maintain the solubility and folding state of such proteins, particularly under stress conditions, is largely unknown. Here, we argue that prion-like low-complexity regions (LCRs) are key regulators of protein solubility and folding. We discuss emerging evidence that prion-like LCRs are not, as commonly thought, autonomous aggregation modules that adopt amyloid-like conformations, but protein-specific sequences with chaperone-like functions. On the basis of recent findings, we propose that prion-like LCRs have evolved to regulate protein phase behavior and to protect proteins against proteotoxic damage.
Collapse
Affiliation(s)
- Titus M Franzmann
- From the Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
| | - Simon Alberti
- From the Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
| |
Collapse
|
298
|
Lampel A, Ulijn RV, Tuttle T. Guiding principles for peptide nanotechnology through directed discovery. Chem Soc Rev 2018; 47:3737-3758. [PMID: 29748676 DOI: 10.1039/c8cs00177d] [Citation(s) in RCA: 100] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Life's diverse molecular functions are largely based on only a small number of highly conserved building blocks - the twenty canonical amino acids. These building blocks are chemically simple, but when they are organized in three-dimensional structures of tremendous complexity, new properties emerge. This review explores recent efforts in the directed discovery of functional nanoscale systems and materials based on these same amino acids, but that are not guided by copying or editing biological systems. The review summarises insights obtained using three complementary approaches of searching the sequence space to explore sequence-structure relationships for assembly, reactivity and complexation, namely: (i) strategic editing of short peptide sequences; (ii) computational approaches to predicting and comparing assembly behaviours; (iii) dynamic peptide libraries that explore the free energy landscape. These approaches give rise to guiding principles on controlling order/disorder, complexation and reactivity by peptide sequence design.
Collapse
Affiliation(s)
- A Lampel
- Advanced Science Research Center (ASRC) at the Graduate Center, City University of New York (CUNY), New York, NY, USA.
| | | | | |
Collapse
|
299
|
Boeynaems S, Alberti S, Fawzi NL, Mittag T, Polymenidou M, Rousseau F, Schymkowitz J, Shorter J, Wolozin B, Van Den Bosch L, Tompa P, Fuxreiter M. Protein Phase Separation: A New Phase in Cell Biology. Trends Cell Biol 2018. [PMID: 29602697 DOI: 10.1016/j.tcb.2018.1002.1004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/30/2023]
Abstract
Cellular compartments and organelles organize biological matter. Most well-known organelles are separated by a membrane boundary from their surrounding milieu. There are also many so-called membraneless organelles and recent studies suggest that these organelles, which are supramolecular assemblies of proteins and RNA molecules, form via protein phase separation. Recent discoveries have shed light on the molecular properties, formation, regulation, and function of membraneless organelles. A combination of techniques from cell biology, biophysics, physical chemistry, structural biology, and bioinformatics are starting to help establish the molecular principles of an emerging field, thus paving the way for exciting discoveries, including novel therapeutic approaches for the treatment of age-related disorders.
Collapse
Affiliation(s)
- Steven Boeynaems
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA; KU Leuven, Department of Neurosciences, Experimental Neurology and Leuven Research Institute for Neuroscience and Disease (LIND), Leuven, Belgium; VIB, Center for Brain and Disease Research, Laboratory of Neurobiology, Leuven, Belgium.
| | - Simon Alberti
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Nicolas L Fawzi
- Department of Molecular Pharmacology, Physiology, and Biotechnology, Brown University, Providence, RI, USA
| | - Tanja Mittag
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | | | - Frederic Rousseau
- Switch Laboratory, VIB, Leuven, Belgium; KU Leuven, Department for Cellular and Molecular Medicine, Leuven, Belgium
| | - Joost Schymkowitz
- Switch Laboratory, VIB, Leuven, Belgium; KU Leuven, Department for Cellular and Molecular Medicine, Leuven, Belgium
| | - James Shorter
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Benjamin Wolozin
- Department of Pharmacology, Boston University School of Medicine, Boston, MA, USA; Department of Neurology, Boston University School of Medicine, Boston, MA, USA
| | - Ludo Van Den Bosch
- KU Leuven, Department of Neurosciences, Experimental Neurology and Leuven Research Institute for Neuroscience and Disease (LIND), Leuven, Belgium; VIB, Center for Brain and Disease Research, Laboratory of Neurobiology, Leuven, Belgium.
| | - Peter Tompa
- VIB, Center for Structural Biology (CSB), Vrije Universiteit Brussel (VUB), Brussels, Belgium; Institute of Enzymology, Research Centre for Natural Sciences of the Hungarian Academy of Sciences, Budapest, Hungary.
| | - Monika Fuxreiter
- MTA-DE Laboratory of Protein Dynamics, Department of Biochemistry and Molecular Biology, University of Debrecen, Debrecen, Hungary.
| |
Collapse
|
300
|
Boeynaems S, Alberti S, Fawzi NL, Mittag T, Polymenidou M, Rousseau F, Schymkowitz J, Shorter J, Wolozin B, Van Den Bosch L, Tompa P, Fuxreiter M. Protein Phase Separation: A New Phase in Cell Biology. Trends Cell Biol 2018; 28:420-435. [PMID: 29602697 PMCID: PMC6034118 DOI: 10.1016/j.tcb.2018.02.004] [Citation(s) in RCA: 1243] [Impact Index Per Article: 207.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Revised: 02/06/2018] [Accepted: 02/13/2018] [Indexed: 12/26/2022]
Abstract
Cellular compartments and organelles organize biological matter. Most well-known organelles are separated by a membrane boundary from their surrounding milieu. There are also many so-called membraneless organelles and recent studies suggest that these organelles, which are supramolecular assemblies of proteins and RNA molecules, form via protein phase separation. Recent discoveries have shed light on the molecular properties, formation, regulation, and function of membraneless organelles. A combination of techniques from cell biology, biophysics, physical chemistry, structural biology, and bioinformatics are starting to help establish the molecular principles of an emerging field, thus paving the way for exciting discoveries, including novel therapeutic approaches for the treatment of age-related disorders.
Collapse
Affiliation(s)
- Steven Boeynaems
- Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA; KU Leuven, Department of Neurosciences, Experimental Neurology and Leuven Research Institute for Neuroscience and Disease (LIND), Leuven, Belgium; VIB, Center for Brain and Disease Research, Laboratory of Neurobiology, Leuven, Belgium.
| | - Simon Alberti
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Nicolas L. Fawzi
- Department of Molecular Pharmacology, Physiology, and Biotechnology, Brown University, Providence, RI, USA
| | - Tanja Mittag
- Department of Structural Biology, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | | | - Frederic Rousseau
- Switch Laboratory, VIB, Leuven, Belgium,KU Leuven, Department for Cellular and Molecular Medicine, Leuven, Belgium
| | - Joost Schymkowitz
- Switch Laboratory, VIB, Leuven, Belgium,KU Leuven, Department for Cellular and Molecular Medicine, Leuven, Belgium
| | - James Shorter
- Department of Biochemistry and Biophysics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, PA, USA
| | - Benjamin Wolozin
- Department of Pharmacology, Boston University School of Medicine, Boston, MA, USA,Department of Neurology, Boston University School of Medicine, Boston, MA, USA
| | - Ludo Van Den Bosch
- KU Leuven, Department of Neurosciences, Experimental Neurology and Leuven Research Institute for Neuroscience and Disease (LIND), Leuven, Belgium; VIB, Center for Brain and Disease Research, Laboratory of Neurobiology, Leuven, Belgium.
| | - Peter Tompa
- VIB, Center for Structural Biology (CSB), Vrije Universiteit Brussel (VUB), Brussels, Belgium; Institute of Enzymology, Research Centre for Natural Sciences of the Hungarian Academy of Sciences, Budapest, Hungary.
| | - Monika Fuxreiter
- MTA-DE Laboratory of Protein Dynamics, Department of Biochemistry and Molecular Biology, University of Debrecen, Debrecen, Hungary.
| |
Collapse
|