1
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Sood A, Zhang B. Preserving condensate structure and composition by lowering sequence complexity. Biophys J 2024; 123:1815-1826. [PMID: 38824391 DOI: 10.1016/j.bpj.2024.05.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Revised: 04/25/2024] [Accepted: 05/28/2024] [Indexed: 06/03/2024] Open
Abstract
Biomolecular condensates play a vital role in organizing cellular chemistry. They selectively partition biomolecules, preventing unwanted cross talk and buffering against chemical noise. Intrinsically disordered proteins (IDPs) serve as primary components of these condensates due to their flexibility and ability to engage in multivalent interactions, leading to spontaneous aggregation. Theoretical advancements are critical at connecting IDP sequences with condensate emergent properties to establish the so-called molecular grammar. We proposed an extension to the stickers and spacers model, incorporating heterogeneous, nonspecific pairwise interactions between spacers alongside specific interactions among stickers. Our investigation revealed that although spacer interactions contribute to phase separation and co-condensation, their nonspecific nature leads to disorganized condensates. Specific sticker-sticker interactions drive the formation of condensates with well-defined networked structures and molecular composition. We discussed how evolutionary pressures might emerge to affect these interactions, leading to the prevalence of low-complexity domains in IDP sequences. These domains suppress spurious interactions and facilitate the formation of biologically meaningful condensates.
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Affiliation(s)
- Amogh Sood
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts
| | - Bin Zhang
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts.
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2
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Higbee PS, Dayhoff GW, Anbanandam A, Varma S, Daughdrill G. Structural Adaptation of Secondary p53 Binding Sites on MDM2 and MDMX. J Mol Biol 2024; 436:168626. [PMID: 38810774 DOI: 10.1016/j.jmb.2024.168626] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 04/24/2024] [Accepted: 05/18/2024] [Indexed: 05/31/2024]
Abstract
The thermodynamics of secondary p53 binding sites on MDM2 and MDMX were evaluated using p53 peptides containing residues 16-29, 17-35, and 1-73. All the peptides had large, negative heat capacity (ΔCp), consistent with the burial of p53 residues F19, W23, and L26 in the primary binding sites of MDM2 and MDMX. MDMX has a higher affinity and more negative ΔCp than MDM2 for p5317-35, which is due to MDMX stabilization and not additional interactions with the secondary binding site. ΔCp measurements show binding to the secondary site is inhibited by the disordered tails of MDM2 for WT p53 but not a more helical mutant where proline 27 is changed to alanine. This result is supported by all-atom molecular dynamics simulations showing that p53 residues 30-35 turn away from the disordered tails of MDM2 in P27A17-35 and make direct contact with this region in p5317-35. Molecular dynamics simulations also suggest that an intramolecular methionine-aromatic motif found in both MDM2 and MDMX structurally adapts to support multiple p53 binding modes with the secondary site. ΔCp measurements also show that tighter binding of the P27A mutant to MDM2 and MDMX is due to increased helicity, which reduces the energetic penalty associated with coupled folding and binding. Our results will facilitate the design of selective p53 inhibitors for MDM2 and MDMX.
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Affiliation(s)
- Pirada Serena Higbee
- The Department of Molecular Biosciences, University of South Florida, 4202 E. Fowler Ave, Tampa, FL 33620, USA
| | - Guy W Dayhoff
- The Department of Chemistry, University of South Florida, 4202 E. Fowler Ave, Tampa, FL 33620, USA
| | - Asokan Anbanandam
- The Department of Molecular Biosciences, University of South Florida, 4202 E. Fowler Ave, Tampa, FL 33620, USA
| | - Sameer Varma
- The Department of Molecular Biosciences, University of South Florida, 4202 E. Fowler Ave, Tampa, FL 33620, USA; The Department of Physics, University of South Florida, 4202 E. Fowler Ave, Tampa, FL 33620, USA
| | - Gary Daughdrill
- The Department of Molecular Biosciences, University of South Florida, 4202 E. Fowler Ave, Tampa, FL 33620, USA.
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3
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Nguyen A, Zhao H, Myagmarsuren D, Srinivasan S, Wu D, Chen J, Piszczek G, Schuck P. Modulation of biophysical properties of nucleocapsid protein in the mutant spectrum of SARS-CoV-2. eLife 2024; 13:RP94836. [PMID: 38941236 PMCID: PMC11213569 DOI: 10.7554/elife.94836] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/30/2024] Open
Abstract
Genetic diversity is a hallmark of RNA viruses and the basis for their evolutionary success. Taking advantage of the uniquely large genomic database of SARS-CoV-2, we examine the impact of mutations across the spectrum of viable amino acid sequences on the biophysical phenotypes of the highly expressed and multifunctional nucleocapsid protein. We find variation in the physicochemical parameters of its extended intrinsically disordered regions (IDRs) sufficient to allow local plasticity, but also observe functional constraints that similarly occur in related coronaviruses. In biophysical experiments with several N-protein species carrying mutations associated with major variants, we find that point mutations in the IDRs can have nonlocal impact and modulate thermodynamic stability, secondary structure, protein oligomeric state, particle formation, and liquid-liquid phase separation. In the Omicron variant, distant mutations in different IDRs have compensatory effects in shifting a delicate balance of interactions controlling protein assembly properties, and include the creation of a new protein-protein interaction interface in the N-terminal IDR through the defining P13L mutation. A picture emerges where genetic diversity is accompanied by significant variation in biophysical characteristics of functional N-protein species, in particular in the IDRs.
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Affiliation(s)
- Ai Nguyen
- Laboratory of Dynamics of Macromolecular Assembly, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, United States
| | - Huaying Zhao
- Laboratory of Dynamics of Macromolecular Assembly, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, United States
| | - Dulguun Myagmarsuren
- Laboratory of Dynamics of Macromolecular Assembly, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, United States
| | - Sanjana Srinivasan
- Laboratory of Dynamics of Macromolecular Assembly, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, United States
| | - Di Wu
- Biophysics Core Facility, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, United States
| | - Jiji Chen
- Advanced Imaging and Microscopy Resource, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, United States
| | - Grzegorz Piszczek
- Biophysics Core Facility, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, United States
| | - Peter Schuck
- Laboratory of Dynamics of Macromolecular Assembly, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, United States
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4
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Alston JJ, Soranno A, Holehouse AS. Conserved molecular recognition by an intrinsically disordered region in the absence of sequence conservation. RESEARCH SQUARE 2024:rs.3.rs-4477977. [PMID: 38883712 PMCID: PMC11177979 DOI: 10.21203/rs.3.rs-4477977/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2024]
Abstract
Intrinsically disordered regions (IDRs) are critical for cellular function yet often appear to lack sequence conservation when assessed by multiple sequence alignments. This raises the question of if and how function can be encoded and preserved in these regions despite massive sequence variation. To address this question, we have applied coarse-grained molecular dynamics simulations to investigate non-specific RNA binding of coronavirus nucleocapsid proteins. Coronavirus nucleocapsid proteins consist of multiple interspersed disordered and folded domains that bind RNA. Here, we focus on the first two domains of coronavirus nucleocapsid proteins: the disordered N-terminal domain (NTD) and the folded RNA binding domain (RBD). While the NTD is highly variable across evolution, the RBD is structurally conserved. This combination makes the NTD-RBD a convenient model system for exploring the interplay between an IDR adjacent to a folded domain and how changes in IDR sequence can influence molecular recognition of a partner. Our results reveal a surprising degree of sequence-specificity encoded by both the composition and the precise order of the amino acids in the NTD. The presence of an NTD can - depending on the sequence - either suppress or enhance RNA binding. Despite this sensitivity, large-scale variation in NTD sequences is possible while certain sequence features are retained. Consequently, a conformationally-conserved dynamic and disordered RNA:protein complex is found across nucleocapsid protein orthologs despite large-scale changes in both NTD sequence and RBD surface chemistry. Taken together, these insights shed light on the ability of disordered regions to preserve functional characteristics despite their sequence variability.
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Affiliation(s)
- Jhullian J. Alston
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA
- Center for Biomolecular Condensates, Washington University in St. Louis, St. Louis, MO, USA
- Present Address, Program In Cellular and Molecular Medicine (PCMM), Boston Children’s Hospital, Boston, MA, USA
| | - Andrea Soranno
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA
- Center for Biomolecular Condensates, Washington University in St. Louis, St. Louis, MO, USA
| | - Alex S. Holehouse
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO 63110, USA
- Center for Biomolecular Condensates, Washington University in St. Louis, St. Louis, MO, USA
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5
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Gupta MN, Uversky VN. Protein structure-function continuum model: Emerging nexuses between specificity, evolution, and structure. Protein Sci 2024; 33:e4968. [PMID: 38532700 DOI: 10.1002/pro.4968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2023] [Revised: 02/18/2024] [Accepted: 03/05/2024] [Indexed: 03/28/2024]
Abstract
The rationale for replacing the old binary of structure-function with the trinity of structure, disorder, and function has gained considerable ground in recent years. A continuum model based on the expanded form of the existing paradigm can now subsume importance of both conformational flexibility and intrinsic disorder in protein function. The disorder is actually critical for understanding the protein-protein interactions in many regulatory processes, formation of membrane-less organelles, and our revised notions of specificity as amply illustrated by moonlighting proteins. While its importance in formation of amyloids and function of prions is often discussed, the roles of intrinsic disorder in infectious diseases and protein function under extreme conditions are also becoming clear. This review is an attempt to discuss how our current understanding of protein function, specificity, and evolution fit better with the continuum model. This integration of structure and disorder under a single model may bring greater clarity in our continuing quest for understanding proteins and molecular mechanisms of their functionality.
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Affiliation(s)
- Munishwar Nath Gupta
- Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology, New Delhi, India
| | - Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
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6
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Nguyen A, Zhao H, Myagmarsuren D, Srinivasan S, Wu D, Chen J, Piszczek G, Schuck P. Modulation of Biophysical Properties of Nucleocapsid Protein in the Mutant Spectrum of SARS-CoV-2. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.11.21.568093. [PMID: 38045241 PMCID: PMC10690151 DOI: 10.1101/2023.11.21.568093] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
Genetic diversity is a hallmark of RNA viruses and the basis for their evolutionary success. Taking advantage of the uniquely large genomic database of SARS-CoV-2, we examine the impact of mutations across the spectrum of viable amino acid sequences on the biophysical phenotypes of the highly expressed and multifunctional nucleocapsid protein. We find variation in the physicochemical parameters of its extended intrinsically disordered regions (IDRs) sufficient to allow local plasticity, but also exhibiting functional constraints that similarly occur in related coronaviruses. In biophysical experiments with several N-protein species carrying mutations associated with major variants, we find that point mutations in the IDRs can have nonlocal impact and modulate thermodynamic stability, secondary structure, protein oligomeric state, particle formation, and liquid-liquid phase separation. In the Omicron variant, distant mutations in different IDRs have compensatory effects in shifting a delicate balance of interactions controlling protein assembly properties, and include the creation of a new protein-protein interaction interface in the N-terminal IDR through the defining P13L mutation. A picture emerges where genetic diversity is accompanied by significant variation in biophysical characteristics of functional N-protein species, in particular in the IDRs.
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Affiliation(s)
- Ai Nguyen
- Laboratory of Dynamics of Macromolecular Assembly, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA
| | - Huaying Zhao
- Laboratory of Dynamics of Macromolecular Assembly, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA
| | - Dulguun Myagmarsuren
- Laboratory of Dynamics of Macromolecular Assembly, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA
| | - Sanjana Srinivasan
- Laboratory of Dynamics of Macromolecular Assembly, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA
| | - Di Wu
- Biophysics Core Facility, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Jiji Chen
- Advanced Imaging and Microscopy Resource, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA
| | - Grzegorz Piszczek
- Biophysics Core Facility, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Peter Schuck
- Laboratory of Dynamics of Macromolecular Assembly, National Institute of Biomedical Imaging and Bioengineering, National Institutes of Health, Bethesda, MD 20892, USA
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7
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Ramesh H, Bhuyan AK. The food and pharmaceutical additive benzoic acid induces amyloid fibrillation of an intrinsically disordered protein. Biophys Chem 2024; 306:107172. [PMID: 38183957 DOI: 10.1016/j.bpc.2024.107172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2023] [Revised: 12/10/2023] [Accepted: 01/01/2024] [Indexed: 01/08/2024]
Abstract
Benzoic acid (BA) is a microbe-inhibiting flavoring agent used extensively as an additive in foods, pharmaceuticals, and hygiene and cosmetic products. The level of BA in foodstuffs prescribed by world bodies and governmental agencies is assumed to be safe so as to prevent adverse health effects. The safety level of BA is however controversial, and whether different conditions of its use would be generally regarded as safe (GRAS) has been rarely determined. In the quest of how food additives affect the structure and conformation of proteins, this study evaluates the interaction of BA with an intrinsically disordered protein (IDP) at pH 4.2 that matches the pH conditions applicable for the commercial use of benzoate preservatives, and examines its structural transformation by NMR, fluorescence, and high-resolution microscopy. The interaction with BA transforms the protein to a denatured aggregated mesophase that undergoes reconfiguration to yield rigid amyloid fibrils. Significantly, fibrils are observed even with 0.1 mM BA while the recommended level of its use as a preservative is in the 0.4-8 mM range. The discussion refrains from safety comments with no projection of the BA level that could be GRAS.
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Affiliation(s)
- Halavath Ramesh
- School of Chemistry, University of Hyderabad, Hyderabad 500046, India
| | - Abani K Bhuyan
- School of Chemistry, University of Hyderabad, Hyderabad 500046, India.
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8
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Lotthammer JM, Ginell GM, Griffith D, Emenecker RJ, Holehouse AS. Direct prediction of intrinsically disordered protein conformational properties from sequence. Nat Methods 2024; 21:465-476. [PMID: 38297184 PMCID: PMC10927563 DOI: 10.1038/s41592-023-02159-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Accepted: 12/20/2023] [Indexed: 02/02/2024]
Abstract
Intrinsically disordered regions (IDRs) are ubiquitous across all domains of life and play a range of functional roles. While folded domains are generally well described by a stable three-dimensional structure, IDRs exist in a collection of interconverting states known as an ensemble. This structural heterogeneity means that IDRs are largely absent from the Protein Data Bank, contributing to a lack of computational approaches to predict ensemble conformational properties from sequence. Here we combine rational sequence design, large-scale molecular simulations and deep learning to develop ALBATROSS, a deep-learning model for predicting ensemble dimensions of IDRs, including the radius of gyration, end-to-end distance, polymer-scaling exponent and ensemble asphericity, directly from sequences at a proteome-wide scale. ALBATROSS is lightweight, easy to use and accessible as both a locally installable software package and a point-and-click-style interface via Google Colab notebooks. We first demonstrate the applicability of our predictors by examining the generalizability of sequence-ensemble relationships in IDRs. Then, we leverage the high-throughput nature of ALBATROSS to characterize the sequence-specific biophysical behavior of IDRs within and between proteomes.
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Affiliation(s)
- Jeffrey M Lotthammer
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO, USA
- Center for Biomolecular Condensates, Washington University in St. Louis, St. Louis, MO, USA
| | - Garrett M Ginell
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO, USA
- Center for Biomolecular Condensates, Washington University in St. Louis, St. Louis, MO, USA
| | - Daniel Griffith
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO, USA
- Center for Biomolecular Condensates, Washington University in St. Louis, St. Louis, MO, USA
| | - Ryan J Emenecker
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO, USA
- Center for Biomolecular Condensates, Washington University in St. Louis, St. Louis, MO, USA
| | - Alex S Holehouse
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO, USA.
- Center for Biomolecular Condensates, Washington University in St. Louis, St. Louis, MO, USA.
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9
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Holehouse AS, Kragelund BB. The molecular basis for cellular function of intrinsically disordered protein regions. Nat Rev Mol Cell Biol 2024; 25:187-211. [PMID: 37957331 DOI: 10.1038/s41580-023-00673-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/26/2023] [Indexed: 11/15/2023]
Abstract
Intrinsically disordered protein regions exist in a collection of dynamic interconverting conformations that lack a stable 3D structure. These regions are structurally heterogeneous, ubiquitous and found across all kingdoms of life. Despite the absence of a defined 3D structure, disordered regions are essential for cellular processes ranging from transcriptional control and cell signalling to subcellular organization. Through their conformational malleability and adaptability, disordered regions extend the repertoire of macromolecular interactions and are readily tunable by their structural and chemical context, making them ideal responders to regulatory cues. Recent work has led to major advances in understanding the link between protein sequence and conformational behaviour in disordered regions, yet the link between sequence and molecular function is less well defined. Here we consider the biochemical and biophysical foundations that underlie how and why disordered regions can engage in productive cellular functions, provide examples of emerging concepts and discuss how protein disorder contributes to intracellular information processing and regulation of cellular function.
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Affiliation(s)
- Alex S Holehouse
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St Louis, MO, USA.
- Center for Biomolecular Condensates, Washington University in St Louis, St Louis, MO, USA.
| | - Birthe B Kragelund
- REPIN, Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, Copenhagen, Denmark.
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10
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Saikia B, Baruah A. Recent advances in de novo computational design and redesign of intrinsically disordered proteins and intrinsically disordered protein regions. Arch Biochem Biophys 2024; 752:109857. [PMID: 38097100 DOI: 10.1016/j.abb.2023.109857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 12/10/2023] [Accepted: 12/10/2023] [Indexed: 12/17/2023]
Abstract
In the early 2000s, the concept of "unstructured biology" has emerged to be an important field in protein science by generating various new research directions. Many novel strategies and methods have been developed that are focused on effectively identifying/predicting intrinsically disordered proteins (IDPs) and intrinsically disordered protein regions (IDPRs), identifying their potential functions, disorder based drug design etc. Due to the range of functions of IDPs/IDPRs and their involvement in various debilitating diseases they are of contemporary interest to the scientific community. Recent researches are focused on designing/redesigning specific IDPs/IDPRs de novo. These de novo design/redesigns of IDPs/IDPRs are carried out by altering compositional biases and specific sequence patterning parameters. The main focus of these researches is to influence specific molecular functions, phase behavior, cellular phenotypes etc. In this review, we first provide the differences of natively folded and natively unfolded or IDPs with respect to their potential energy landscapes. Here, we provide current understandings on the different computational design strategies and methods that have been utilized in de novo design and redesigns of IDPs and IDPRs. Finally, we conclude the review by discussing the challenges that have been faced during the computational design/design attempts of IDPs/IDPRs.
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Affiliation(s)
- Bondeepa Saikia
- Department of Chemistry, Dibrugarh University, Dibrugarh, 786004, Assam, India
| | - Anupaul Baruah
- Department of Chemistry, Dibrugarh University, Dibrugarh, 786004, Assam, India.
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11
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Dagher SF, Vaishnav A, Stanley CB, Meilleur F, Edwards BFP, Bruno-Bárcena JM. Structural analysis and functional evaluation of the disordered ß-hexosyltransferase region from Hamamotoa (Sporobolomyces) singularis. Front Bioeng Biotechnol 2023; 11:1291245. [PMID: 38162180 PMCID: PMC10755861 DOI: 10.3389/fbioe.2023.1291245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Accepted: 11/16/2023] [Indexed: 01/03/2024] Open
Abstract
Hamamotoa (Sporobolomyces) singularis codes for an industrially important membrane bound ß-hexosyltransferase (BHT), (BglA, UniprotKB: Q564N5) that has applications in the production of natural fibers such as galacto-oligosaccharides (GOS) and natural sugars found in human milk. When heterologously expressed by Komagataella phaffii GS115, BHT is found both membrane bound and soluble secreted into the culture medium. In silico structural predictions and crystal structures support a glycosylated homodimeric enzyme and the presence of an intrinsically disordered region (IDR) with membrane binding potential within its novel N-terminal region (1-110 amino acids). Additional in silico analysis showed that the IDR may not be essential for stable homodimerization. Thus, we performed progressive deletion analyses targeting segments within the suspected disordered region, to determine the N-terminal disorder region's impact on the ratio of membrane-bound to secreted soluble enzyme and its contribution to enzyme activity. The ratio of the soluble secreted to membrane-bound enzyme shifted from 40% to 53% after the disordered N-terminal region was completely removed, while the specific activity was unaffected. Furthermore, functional analysis of each glycosylation site found within the C-terminal domain revealed reduced total secreted protein activity by 58%-97% in both the presence and absence of the IDR, indicating that glycosylation at all four locations is required by the host for the secretion of active enzyme and independent of the removed disordered N-terminal region. Overall, the data provides evidence that the disordered region only partially influences the secretion and membrane localization of BHT.
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Affiliation(s)
- Suzanne F. Dagher
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC, United States
| | - Asmita Vaishnav
- Department of Biochemistry, Microbiology and Immunology, Wayne State University, Detroit, MI, United States
| | | | - Flora Meilleur
- Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, TN, United States
- Department of Molecular and Structural Biochemistry, North Carolina State University, Raleigh, NC, United States
| | - Brian F. P. Edwards
- Department of Biochemistry, Microbiology and Immunology, Wayne State University, Detroit, MI, United States
| | - José M. Bruno-Bárcena
- Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC, United States
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12
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McConnell BS, Parker MW. Protein intrinsically disordered regions have a non-random, modular architecture. Bioinformatics 2023; 39:btad732. [PMID: 38039154 PMCID: PMC10719218 DOI: 10.1093/bioinformatics/btad732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 11/03/2023] [Accepted: 11/30/2023] [Indexed: 12/03/2023] Open
Abstract
MOTIVATION Protein sequences can be broadly categorized into two classes: those which adopt stable secondary structure and fold into a domain (i.e. globular proteins), and those that do not. The sequences belonging to this latter class are conformationally heterogeneous and are described as being intrinsically disordered. Decades of investigation into the structure and function of globular proteins has resulted in a suite of computational tools that enable their sub-classification by domain type, an approach that has revolutionized how we understand and predict protein functionality. Conversely, it is unknown if sequences of disordered protein regions are subject to broadly generalizable organizational principles that would enable their sub-classification. RESULTS Here, we report the development of a statistical approach that quantifies linear variance in amino acid composition across a sequence. With multiple examples, we provide evidence that intrinsically disordered regions are organized into statistically non-random modules of unique compositional bias. Modularity is observed for both low and high-complexity sequences and, in some cases, we find that modules are organized in repetitive patterns. These data demonstrate that disordered sequences are non-randomly organized into modular architectures and motivate future experiments to comprehensively classify module types and to determine the degree to which modules constitute functionally separable units analogous to the domains of globular proteins. AVAILABILITY AND IMPLEMENTATION The source code, documentation, and data to reproduce all figures are freely available at https://github.com/MWPlabUTSW/Chi-Score-Analysis.git. The analysis is also available as a Google Colab Notebook (https://colab.research.google.com/github/MWPlabUTSW/Chi-Score-Analysis/blob/main/ChiScore_Analysis.ipynb).
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Affiliation(s)
- Brendan S McConnell
- Department of Biophysics, , University of Texas Southwestern Medical Center, Dallas, TX 75235, United States
| | - Matthew W Parker
- Department of Biophysics, , University of Texas Southwestern Medical Center, Dallas, TX 75235, United States
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13
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Fenton M, Gregory E, Daughdrill G. Protein disorder and autoinhibition: The role of multivalency and effective concentration. Curr Opin Struct Biol 2023; 83:102705. [PMID: 37778184 PMCID: PMC10841074 DOI: 10.1016/j.sbi.2023.102705] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Revised: 08/25/2023] [Accepted: 08/28/2023] [Indexed: 10/03/2023]
Abstract
Regulation of protein binding through autoinhibition commonly occurs via interactions involving intrinsically disordered regions (IDRs). These intramolecular interactions can directly or allosterically inhibit intermolecular protein or DNA binding, regulate enzymatic activity, and control the assembly of large macromolecular complexes. Autoinhibitory interactions mediated by protein disorder are inherently transient, making their identification and characterization challenging. In this review, we explore the structural and functional diversity of disorder-mediated autoinhibition for a variety of biological mechanisms, with a focus on the role of multivalency and effective concentration. We also discuss the evolution of disordered motifs that participate in autoinhibition using examples where sequence conservation varies from high to low. In some cases, identifiable motifs that are essential for autoinhibition remain intact within a rapidly evolving sequence, over long evolutionary distances. Finally, we examine the potential of AlphaFold2 to predict autoinhibitory intramolecular interactions involving IDRs.
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Affiliation(s)
- Malissa Fenton
- Department of Molecular Biosciences, University of South Florida, Tampa, FL 33620, USA
| | - Emily Gregory
- Department of Molecular Biosciences, University of South Florida, Tampa, FL 33620, USA
| | - Gary Daughdrill
- Department of Molecular Biosciences, University of South Florida, Tampa, FL 33620, USA.
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14
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McDonald NA, Tao L, Dong MQ, Shen K. SAD-1 kinase controls presynaptic phase separation by relieving SYD-2/Liprin-α autoinhibition. PLoS Biol 2023; 21:e3002421. [PMID: 38048304 PMCID: PMC10695385 DOI: 10.1371/journal.pbio.3002421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 11/06/2023] [Indexed: 12/06/2023] Open
Abstract
Neuronal development orchestrates the formation of an enormous number of synapses that connect the nervous system. In developing presynapses, the core active zone structure has been found to assemble through liquid-liquid phase separation. Here, we find that the phase separation of Caenorhabditis elegans SYD-2/Liprin-α, a key active zone scaffold, is controlled by phosphorylation. We identify the SAD-1 kinase as a regulator of SYD-2 phase separation and determine presynaptic assembly is impaired in sad-1 mutants and increased by overactivation of SAD-1. Using phosphoproteomics, we find SAD-1 phosphorylates SYD-2 on 3 sites that are critical to activate phase separation. Mechanistically, SAD-1 phosphorylation relieves a binding interaction between 2 folded domains in SYD-2 that inhibits phase separation by an intrinsically disordered region (IDR). We find synaptic cell adhesion molecules localize SAD-1 to nascent synapses upstream of active zone formation. We conclude that SAD-1 phosphorylates SYD-2 at developing synapses, activating its phase separation and active zone assembly.
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Affiliation(s)
- Nathan A. McDonald
- Department of Biology, Stanford University, Stanford, California, United States of America
| | - Li Tao
- Department of Biology, Stanford University, Stanford, California, United States of America
| | - Meng-Qiu Dong
- National Institute of Biological Sciences, Beijing, People’s Republic of China
| | - Kang Shen
- Department of Biology, Stanford University, Stanford, California, United States of America
- Howard Hughes Medical Institute, Stanford University, Stanford, California, United States of America
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15
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Sood A, Zhang B. Preserving condensate structure and composition by lowering sequence complexity. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.29.569249. [PMID: 38076908 PMCID: PMC10705451 DOI: 10.1101/2023.11.29.569249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/22/2023]
Abstract
Biological condensates play a vital role in organizing cellular chemistry. They selectively partition biomolecules, preventing unwanted cross-talk and buffering against chemical noise. Intrinsically disordered proteins (IDPs) serve as primary components of these condensates due to their flexibility and ability to engage in multivalent, non-specific interactions, leading to spontaneous aggregation. Theoretical advancements are critical at connecting IDP sequences with condensate emergent properties to establish the so-called molecular grammar. We proposed an extension to the stickers and spacers model, incorporating non-specific pairwise interactions between spacers alongside specific interactions among stickers. Our investigation revealed that while spacer interactions contribute to phase separation and co-condensation, their non-specific nature leads to disorganized condensates. Specific sticker-sticker interactions drive the formation of condensates with well-defined structures and molecular composition. We discussed how evolutionary pressures might emerge to affect these interactions, leading to the prevalence of low complexity domains in IDP sequences. These domains suppress spurious interactions and facilitate the formation of biologically meaningful condensates.
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Affiliation(s)
- Amogh Sood
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Bin Zhang
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
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16
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Stormo BM, McLaughlin GA, Frederick LK, Jalihal AP, Cole SJ, Seim I, Dietrich FS, Gladfelter AS. Biomolecular condensates in fungi are tuned to function at specific temperatures. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.27.568884. [PMID: 38076832 PMCID: PMC10705276 DOI: 10.1101/2023.11.27.568884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/24/2023]
Abstract
Temperature can impact every reaction and molecular interaction essential to a cell. For organisms that cannot regulate their own temperature, a major challenge is how to adapt to temperatures that fluctuate unpredictability and on variable timescales. Biomolecular condensation offers a possible mechanism for encoding temperature-responsiveness and robustness into cell biochemistry and organization. To explore this idea, we examined temperature adaptation in a filamentous-growing fungus called Ashbya gossypii that engages biomolecular condensates containing the RNA-binding protein Whi3 to regulate mitosis and morphogenesis. We collected wild isolates of Ashbya that originate in different climates and found that mitotic asynchrony and polarized growth, which are known to be controlled by the condensation of Whi3, are temperature sensitive. Sequence analysis in the wild strains revealed changes to specific domains within Whi3 known to be important in condensate formation. Using an in vitro condensate reconstitution assay we found that temperature impacts the relative abundance of protein to RNA within condensates and that this directly impacts the material properties of the droplets. Finally, we found that exchanging Whi3 genes between warm and cold isolates was sufficient to rescue some, but not all, condensate-related phenotypes. Together these data demonstrate that material properties of Whi3 condensates are temperature sensitive, that these properties are important for function, and that sequence optimizes properties for a given climate.
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Affiliation(s)
| | - Grace A. McLaughlin
- Duke University, Department of Cell Biology, Durham, NC
- University of North Carolina, Chapel Hill, Department of Biology
| | | | | | - Sierra J Cole
- Duke University, Department of Cell Biology, Durham, NC
- University of North Carolina, Chapel Hill, Department of Biochemistry and Biophysics
| | - Ian Seim
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Fred S. Dietrich
- Duke University, Department of Molecular Genetics and Microbiology, Durham, NC
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17
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Alston JJ, Soranno A. Condensation Goes Viral: A Polymer Physics Perspective. J Mol Biol 2023; 435:167988. [PMID: 36709795 PMCID: PMC10368797 DOI: 10.1016/j.jmb.2023.167988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 01/18/2023] [Accepted: 01/21/2023] [Indexed: 01/27/2023]
Abstract
The past decade has seen a revolution in our understanding of how the cellular environment is organized, where an incredible body of work has provided new insights into the role played by membraneless organelles. These rapid advancements have been made possible by an increasing awareness of the peculiar physical properties that give rise to such bodies and the complex biology that enables their function. Viral infections are not extraneous to this. Indeed, in host cells, viruses can harness existing membraneless compartments or, even, induce the formation of new ones. By hijacking the cellular machinery, these intracellular bodies can assist in the replication, assembly, and packaging of the viral genome as well as in the escape of the cellular immune response. Here, we provide a perspective on the fundamental polymer physics concepts that may help connect and interpret the different observed phenomena, ranging from the condensation of viral genomes to the phase separation of multicomponent solutions. We complement the discussion of the physical basis with a description of biophysical methods that can provide quantitative insights for testing and developing theoretical and computational models.
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Affiliation(s)
- Jhullian J Alston
- Department of Biochemistry and Molecular Biophysics, Washington University in St Louis, 660 St Euclid Ave, 63110 Saint Louis, MO, USA; Center for Biomolecular Condensates, Washington University in St Louis, 1 Brookings Drive, 63130 Saint Louis, MO, USA
| | - Andrea Soranno
- Department of Biochemistry and Molecular Biophysics, Washington University in St Louis, 660 St Euclid Ave, 63110 Saint Louis, MO, USA; Center for Biomolecular Condensates, Washington University in St Louis, 1 Brookings Drive, 63130 Saint Louis, MO, USA.
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18
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Alston JJ, Soranno A, Holehouse AS. Conserved molecular recognition by an intrinsically disordered region in the absence of sequence conservation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.06.552128. [PMID: 37609146 PMCID: PMC10441348 DOI: 10.1101/2023.08.06.552128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
Intrinsically disordered regions (IDRs) are critical for cellular function, yet often appear to lack sequence conservation when assessed by multiple sequence alignments. This raises the question of if and how function can be encoded and preserved in these regions despite massive sequence variation. To address this question, we have applied coarse-grained molecular dynamics simulations to investigate non-specific RNA binding of coronavirus nucleocapsid proteins. Coronavirus nucleocapsid proteins consist of multiple interspersed disordered and folded domains that bind RNA. We focussed here on the first two domains of coronavirus nucleocapsid proteins, the disordered N-terminal domain (NTD) followed by the folded RNA binding domain (RBD). While the NTD is highly variable across evolution, the RBD is structurally conserved. This combination makes the NTD-RBD a convenient model system to explore the interplay between an IDR adjacent to a folded domain, and how changes in IDR sequence can influence molecular recognition of a partner. Our results reveal a surprising degree of sequence-specificity encoded by both the composition and the precise order of the amino acids in the NTD. The presence of an NTD can - depending on the sequence - either suppress or enhance RNA binding. Despite this sensitivity, large-scale variation in NTD sequences is possible while certain sequence features are retained. Consequently, a conformationally-conserved fuzzy RNA:protein complex is found across nucleocapsid protein orthologs, despite large-scale changes in both NTD sequence and RBD surface chemistry. Taken together, these insights shed light on the ability of disordered regions to preserve functional characteristics despite their sequence variability.
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19
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McDonald NA, Tao L, Dong MQ, Shen K. SAD-1 kinase controls presynaptic phase separation by relieving SYD-2/Liprin-α autoinhibition. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.12.544643. [PMID: 37398223 PMCID: PMC10312667 DOI: 10.1101/2023.06.12.544643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Neuronal development orchestrates the formation of an enormous number of synapses that connect the nervous system. In developing presynapses, the core active zone structure has been found to assemble through a liquid-liquid phase separation. Here, we find that the phase separation of SYD-2/Liprin-α, a key active zone scaffold, is controlled by phosphorylation. Using phosphoproteomics, we identify the SAD-1 kinase to phosphorylate SYD-2 and a number of other substrates. Presynaptic assembly is impaired in sad-1 mutants and increased by overactivation of SAD-1. We determine SAD-1 phosphorylation of SYD-2 at three sites is critical to activate its phase separation. Mechanistically, phosphorylation relieves a binding interaction between two folded SYD-2 domains that inhibits phase separation by an intrinsically disordered region. We find synaptic cell adhesion molecules localize SAD-1 to nascent synapses upstream of active zone formation. We conclude that SAD-1 phosphorylates SYD-2 at developing synapses, enabling its phase separation and active zone assembly.
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Affiliation(s)
| | - Li Tao
- Department of Biology, Stanford University, Stanford, CA, USA
| | - Meng-Qiu Dong
- National Institute of Biological Sciences, Beijing, China
| | - Kang Shen
- Department of Biology, Stanford University, Stanford, CA, USA
- Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA
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20
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Zanetti-Polzi L, Daidone I, Iacobucci C, Amadei A. Thermodynamic Evolution of a Metamorphic Protein: A Theoretical-Computational Study of Human Lymphotactin. Protein J 2023:10.1007/s10930-023-10123-7. [PMID: 37233895 DOI: 10.1007/s10930-023-10123-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/03/2023] [Indexed: 05/27/2023]
Abstract
Metamorphic, or fold-switching, proteins feature different folds that are physiologically relevant. The human chemokine XCL1 (or Lymphotactin) is a metamorphic protein that features two native states, an [Formula: see text] and an all[Formula: see text] fold, which have similar stability at physiological condition. Here, extended molecular dynamics (MD) simulations, principal component analysis of atomic fluctuations and thermodynamic modeling based on both the configurational volume and free energy landscape, are used to obtain a detailed characterization of the conformational thermodynamics of human Lymphotactin and of one of its ancestors (as was previously obtained by genetic reconstruction). Comparison of our computational results with the available experimental data show that the MD-based thermodynamics can explain the experimentally observed variation of the conformational equilibrium between the two proteins. In particular, our computational data provide an interpretation of the thermodynamic evolution in this protein, revealing the relevance of the configurational entropy and of the shape of the free energy landscape within the essential space (i.e., the space defined by the generalized internal coordinates providing the largest, typically non-Gaussian, structural fluctuations).
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Affiliation(s)
- Laura Zanetti-Polzi
- Center S3, CNR-Institute of Nanoscience, Via Campi 213/A, 100190, Modena, Italy
| | - Isabella Daidone
- Department of Physical and Chemical Sciences, University of L'Aquila, Via Vetoio (Coppito 1), 67010, L'Aquila, Italy
| | - Claudio Iacobucci
- Department of Physical and Chemical Sciences, University of L'Aquila, Via Vetoio (Coppito 1), 67010, L'Aquila, Italy
| | - Andrea Amadei
- Department of Chemical Science and Technology, University of Rome "Tor Vergata", Via Della Ricerca Scientifica 1, 00185, Rome, Italy.
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21
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Saurabh S, Nadendla K, Purohit SS, Sivakumar PM, Cetinel S. Fuzzy Drug Targets: Disordered Proteins in the Drug-Discovery Realm. ACS OMEGA 2023; 8:9729-9747. [PMID: 36969402 PMCID: PMC10034788 DOI: 10.1021/acsomega.2c07708] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 02/17/2023] [Indexed: 06/18/2023]
Abstract
Intrinsically disordered proteins (IDPs) and regions (IDRs) form a large part of the eukaryotic proteome. Contrary to the structure-function paradigm, the disordered proteins perform a myriad of functions in vivo. Consequently, they are involved in various disease pathways and are plausible drug targets. Unlike folded proteins, that have a defined structure and well carved out drug-binding pockets that can guide lead molecule selection, the disordered proteins require alternative drug-development methodologies that are based on an acceptable picture of their conformational ensemble. In this review, we discuss various experimental and computational techniques that contribute toward understanding IDP "structure" and describe representative pursuances toward IDP-targeting drug development. We also discuss ideas on developing rational drug design protocols targeting IDPs.
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Affiliation(s)
- Suman Saurabh
- Molecular
Sciences Research Hub, Department of Chemistry, Imperial College London, London W12 0BZ, U.K.
| | - Karthik Nadendla
- Center
for Misfolding Diseases, Yusuf Hamied Department of Chemistry, Lensfield
Road, University of Cambridge, Cambridge CB2 1EW, U.K.
| | - Shubh Sanket Purohit
- Department
of Clinical Haematology, Sahyadri Superspeciality
Hospital, Pune, Maharashtra 411038, India
| | - Ponnurengam Malliappan Sivakumar
- Institute
of Research and Development, Duy Tan University, Da Nang 550000, Vietnam
- School
of Medicine and Pharmacy, Duy Tan University, Da Nang 550000, Vietnam
- Nanotechnology
Research and Application Center (SUNUM), Sabanci University, Istanbul 34956, Turkey
| | - Sibel Cetinel
- Nanotechnology
Research and Application Center (SUNUM), Sabanci University, Istanbul 34956, Turkey
- Faculty of
Engineering and Natural Sciences, Molecular Biology, Genetics and
Bioengineering Program, Sabanci University, Istanbul 34956, Turkey
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22
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Chandra S, Manjunath K, Asok A, Varadarajan R. Mutational scan inferred binding energetics and structure in intrinsically disordered protein CcdA. Protein Sci 2023; 32:e4580. [PMID: 36714997 PMCID: PMC9951195 DOI: 10.1002/pro.4580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 01/02/2023] [Accepted: 01/25/2023] [Indexed: 01/31/2023]
Abstract
Unlike globular proteins, mutational effects on the function of Intrinsically Disordered Proteins (IDPs) are not well-studied. Deep Mutational Scanning of a yeast surface displayed mutant library yields insights into sequence-function relationships in the CcdA IDP. The approach enables facile prediction of interface residues and local structural signatures of the bound conformation. In contrast to previous titration-based approaches which use a number of ligand concentrations, we show that use of a single rationally chosen ligand concentration can provide quantitative estimates of relative binding constants for large numbers of protein variants. This is because the extended interface of IDP ensures that energetic effects of point mutations are spread over a much smaller range than for globular proteins. Our data also provides insights into the much-debated role of helicity and disorder in partner binding of IDPs. Based on this exhaustive mutational sensitivity dataset, a rudimentary model was developed in an attempt to predict mutational effects on binding affinity of IDPs that form alpha-helical structures upon binding.
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Affiliation(s)
| | | | - Aparna Asok
- Molecular Biophysics Unit, Indian Institute of ScienceBangaloreIndia
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23
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Kouros CE, Makri V, Ouzounis CA, Chasapi A. Disease association and comparative genomics of compositional bias in human proteins. F1000Res 2023; 12:198. [PMID: 37082000 PMCID: PMC10111144 DOI: 10.12688/f1000research.129929.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 02/02/2023] [Indexed: 02/22/2023] Open
Abstract
Background: The evolutionary rate of disordered proteins varies greatly due to the lack of structural constraints. So far, few studies have investigated the presence/absence patterns of intrinsically disordered regions (IDRs) across phylogenies in conjunction with human disease. In this study, we report a genome-wide analysis of compositional bias association with disease in human proteins and their taxonomic distribution. Methods: The human genome protein set provided by the Ensembl database was annotated and analysed with respect to both disease associations and the detection of compositional bias. The Uniprot Reference Proteome dataset, containing 11297 proteomes was used as target dataset for the comparative genomics of a well-defined subset of the Human Genome, including 100 characteristic, compositionally biased proteins, some linked to disease. Results: Cross-evaluation of compositional bias and disease-association in the human genome reveals a significant bias towards low complexity regions in disease-associated genes, with charged, hydrophilic amino acids appearing as over-represented. The phylogenetic profiling of 17 disease-associated, low complexity proteins across 11297 proteomes captures characteristic taxonomic distribution patterns. Conclusions: This is the first time that a combined genome-wide analysis of low complexity, disease-association and taxonomic distribution of human proteins is reported, covering structural, functional, and evolutionary properties. The reported framework can form the basis for large-scale, follow-up projects, encompassing the entire human genome and all known gene-disease associations.
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Affiliation(s)
- Christos E. Kouros
- BCCB-AIIA, School of Informatics, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Vasiliki Makri
- BCCB-AIIA, School of Informatics, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Christos A. Ouzounis
- BCCB-AIIA, School of Informatics, Aristotle University of Thessaloniki, Thessaloniki, Greece
- BCPL, Chemical Process & Energy Resources Institute, Centre for Research & Technology Hellas (CERTH), Thessaloniki, Greece
| | - Anastasia Chasapi
- BCPL, Chemical Process & Energy Resources Institute, Centre for Research & Technology Hellas (CERTH), Thessaloniki, Greece
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24
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Kim S, Wysocka J. Deciphering the multi-scale, quantitative cis-regulatory code. Mol Cell 2023; 83:373-392. [PMID: 36693380 PMCID: PMC9898153 DOI: 10.1016/j.molcel.2022.12.032] [Citation(s) in RCA: 57] [Impact Index Per Article: 57.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 12/29/2022] [Accepted: 12/30/2022] [Indexed: 01/24/2023]
Abstract
Uncovering the cis-regulatory code that governs when and how much each gene is transcribed in a given genome and cellular state remains a central goal of biology. Here, we discuss major layers of regulation that influence how transcriptional outputs are encoded by DNA sequence and cellular context. We first discuss how transcription factors bind specific DNA sequences in a dosage-dependent and cooperative manner and then proceed to the cofactors that facilitate transcription factor function and mediate the activity of modular cis-regulatory elements such as enhancers, silencers, and promoters. We then consider the complex and poorly understood interplay of these diverse elements within regulatory landscapes and its relationships with chromatin states and nuclear organization. We propose that a mechanistically informed, quantitative model of transcriptional regulation that integrates these multiple regulatory layers will be the key to ultimately cracking the cis-regulatory code.
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Affiliation(s)
- Seungsoo Kim
- Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305, USA; Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Joanna Wysocka
- Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305, USA; Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA.
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25
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Kouros CE, Makri V, Ouzounis CA, Chasapi A. Disease association and comparative genomics of compositional bias in human proteins. F1000Res 2023; 12:198. [PMID: 37082000 PMCID: PMC10111144.2 DOI: 10.12688/f1000research.129929.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/12/2023] [Indexed: 04/25/2023] Open
Abstract
Background: The evolutionary rate of disordered protein regions varies greatly due to the lack of structural constraints. So far, few studies have investigated the presence/absence patterns of compositional bias, indicative of disorder, across phylogenies in conjunction with human disease. In this study, we report a genome-wide analysis of compositional bias association with disease in human proteins and their taxonomic distribution. Methods: The human genome protein set provided by the Ensembl database was annotated and analysed with respect to both disease associations and the detection of compositional bias. The Uniprot Reference Proteome dataset, containing 11297 proteomes was used as target dataset for the comparative genomics of a well-defined subset of the Human Genome, including 100 characteristic, compositionally biased proteins, some linked to disease. Results: Cross-evaluation of compositional bias and disease-association in the human genome reveals a significant bias towards biased regions in disease-associated genes, with charged, hydrophilic amino acids appearing as over-represented. The phylogenetic profiling of 17 disease-associated, proteins with compositional bias across 11297 proteomes captures characteristic taxonomic distribution patterns. Conclusions: This is the first time that a combined genome-wide analysis of compositional bias, disease-association and taxonomic distribution of human proteins is reported, covering structural, functional, and evolutionary properties. The reported framework can form the basis for large-scale, follow-up projects, encompassing the entire human genome and all known gene-disease associations.
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Affiliation(s)
- Christos E. Kouros
- BCCB-AIIA, School of Informatics, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Vasiliki Makri
- BCCB-AIIA, School of Informatics, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Christos A. Ouzounis
- BCCB-AIIA, School of Informatics, Aristotle University of Thessaloniki, Thessaloniki, Greece
- BCPL, Chemical Process & Energy Resources Institute, Centre for Research & Technology Hellas (CERTH), Thessaloniki, Greece
| | - Anastasia Chasapi
- BCPL, Chemical Process & Energy Resources Institute, Centre for Research & Technology Hellas (CERTH), Thessaloniki, Greece
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26
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Evolution of SLiM-mediated hijack functions in intrinsically disordered viral proteins. Essays Biochem 2022; 66:945-958. [DOI: 10.1042/ebc20220059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 11/07/2022] [Accepted: 11/08/2022] [Indexed: 12/07/2022]
Abstract
Abstract
Viruses and their hosts are involved in an ‘arms race’ where they continually evolve mechanisms to overcome each other. It has long been proposed that intrinsic disorder provides a substrate for the evolution of viral hijack functions and that short linear motifs (SLiMs) are important players in this process. Here, we review evidence in support of this tenet from two model systems: the papillomavirus E7 protein and the adenovirus E1A protein. Phylogenetic reconstructions reveal that SLiMs appear and disappear multiple times across evolution, providing evidence of convergent evolution within individual viral phylogenies. Multiple functionally related SLiMs show strong coevolution signals that persist across long distances in the primary sequence and occur in unrelated viral proteins. Moreover, changes in SLiMs are associated with changes in phenotypic traits such as host range and tropism. Tracking viral evolutionary events reveals that host switch events are associated with the loss of several SLiMs, suggesting that SLiMs are under functional selection and that changes in SLiMs support viral adaptation. Fine-tuning of viral SLiM sequences can improve affinity, allowing them to outcompete host counterparts. However, viral SLiMs are not always competitive by themselves, and tethering of two suboptimal SLiMs by a disordered linker may instead enable viral hijack. Coevolution between the SLiMs and the linker indicates that the evolution of disordered regions may be more constrained than previously thought. In summary, experimental and computational studies support a role for SLiMs and intrinsic disorder in viral hijack functions and in viral adaptive evolution.
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27
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Patil A. Enrichment patterns of intrinsic disorder in proteins. Biophys Rev 2022; 14:1487-1493. [PMID: 36659984 PMCID: PMC9842814 DOI: 10.1007/s12551-022-01016-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 11/07/2022] [Indexed: 11/21/2022] Open
Abstract
Intrinsically disordered regions in proteins have been shown to be important in protein function. However, not all proteins contain the same amount of intrinsic disorder. The variation in the levels of intrinsic disorder in different types of proteins has been extensively studied over the last two decades. It is now known that the levels of intrinsic disorder vary in proteins across organisms, functions, diseases, and cellular locations. This review consolidates the known trends in the abundance of intrinsic disorder identified in groups of proteins across varying conditions and functions. It also presents new data towards the understanding of intrinsic disorder in cell type-specific proteins. Supplementary Information The online version contains supplementary material available at 10.1007/s12551-022-01016-7.
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Affiliation(s)
- Ashwini Patil
- Combinatics Inc., 2-2-6 Sugano, Ichikawa-Shi, Chiba, 272-0824 Japan
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28
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Dayhoff GW, Uversky VN. Rapid prediction and analysis of protein intrinsic disorder. Protein Sci 2022; 31:e4496. [PMID: 36334049 PMCID: PMC9679974 DOI: 10.1002/pro.4496] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 10/28/2022] [Accepted: 11/02/2022] [Indexed: 11/07/2022]
Abstract
Protein intrinsic disorder is found in all kingdoms of life and is known to underpin numerous physiological and pathological processes. Computational methods play an important role in characterizing and identifying intrinsically disordered proteins and protein regions. Herein, we present a new high-efficiency web-based disorder predictor named Rapid Intrinsic Disorder Analysis Online (RIDAO) that is designed to facilitate the application of protein intrinsic disorder analysis in genome-scale structural bioinformatics and comparative genomics/proteomics. RIDAO integrates six established disorder predictors into a single, unified platform that reproduces the results of individual predictors with near-perfect fidelity. To demonstrate the potential applications, we construct a test set containing more than one million sequences from one hundred organisms comprising over 420 million residues. Using this test set, we compare the efficiency and accessibility (i.e., ease of use) of RIDAO to five well-known and popular disorder predictors, namely: AUCpreD, IUPred3, metapredict V2, flDPnn, and SPOT-Disorder2. We show that RIDAO yields per-residue predictions at a rate two to six orders of magnitude greater than the other predictors and completely processes the test set in under an hour. RIDAO can be accessed free of charge at https://ridao.app.
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Affiliation(s)
- Guy W. Dayhoff
- Department of ChemistryUniversity of South FloridaTampaFloridaUSA
| | - Vladimir N. Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research InstituteUniversity of South FloridaTampaFloridaUSA
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29
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Intrinsically Disordered Proteins: An Overview. Int J Mol Sci 2022; 23:ijms232214050. [PMID: 36430530 PMCID: PMC9693201 DOI: 10.3390/ijms232214050] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2022] [Revised: 11/07/2022] [Accepted: 11/08/2022] [Indexed: 11/16/2022] Open
Abstract
Many proteins and protein segments cannot attain a single stable three-dimensional structure under physiological conditions; instead, they adopt multiple interconverting conformational states. Such intrinsically disordered proteins or protein segments are highly abundant across proteomes, and are involved in various effector functions. This review focuses on different aspects of disordered proteins and disordered protein regions, which form the basis of the so-called "Disorder-function paradigm" of proteins. Additionally, various experimental approaches and computational tools used for characterizing disordered regions in proteins are discussed. Finally, the role of disordered proteins in diseases and their utility as potential drug targets are explored.
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30
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Lázár T, Tantos A, Tompa P, Schad E. Intrinsic protein disorder uncouples affinity from binding specificity. Protein Sci 2022; 31:e4455. [PMID: 36305763 PMCID: PMC9601785 DOI: 10.1002/pro.4455] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Revised: 09/15/2022] [Accepted: 09/17/2022] [Indexed: 12/29/2022]
Abstract
Intrinsically disordered proteins (IDPs) and intrinsically disordered regions (IDRs) of proteins often function by molecular recognition, in which they undergo induced folding. Based on prior generalizations, the idea prevails in the IDP field that due to the entropic penalty of induced folding, the major functional advantage associated with this binding mode is "uncoupling" specificity from binding strength. Nevertheless, both weaker binding and high specificity of IDPs/IDRs rest on limited experimental observations, making these assumptions more speculations than evidence-supported facts. The issue is also complicated by the rather vague concept of specificity that lacks an exact measure, such as the Kd for binding strength. We addressed these issues by creating and analyzing a comprehensive dataset of well-characterized ID/globular protein complexes, for which both the atomic structure of the complex and free energy (ΔG, Kd ) of interaction is known. Through this analysis, we provide evidence that the affinity distributions of IDP/globular and globular/globular complexes show different trends, whereas specificity does not connote to weaker binding strength of IDPs/IDRs. Furthermore, protein disorder extends the spectrum in the direction of very weak interactions, which may have important regulatory consequences and suggest that, in a biological sense, strict correlation of specificity and binding strength are uncoupled by structural disorder.
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Affiliation(s)
- Tamas Lázár
- VIB‐VUB Center for Structural BiologyFlanders Institute for Biotechnology (VIB)BrusselsBelgium,Structural Biology BrusselsVrije Universiteit BrusselBrusselsBelgium
| | - Agnes Tantos
- Institute of EnzymologyResearch Centre for Natural SciencesBudapestHungary
| | - Peter Tompa
- VIB‐VUB Center for Structural BiologyFlanders Institute for Biotechnology (VIB)BrusselsBelgium,Structural Biology BrusselsVrije Universiteit BrusselBrusselsBelgium,Institute of EnzymologyResearch Centre for Natural SciencesBudapestHungary
| | - Eva Schad
- Institute of EnzymologyResearch Centre for Natural SciencesBudapestHungary
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31
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Ilzhöfer D, Heinzinger M, Rost B. SETH predicts nuances of residue disorder from protein embeddings. FRONTIERS IN BIOINFORMATICS 2022; 2:1019597. [PMID: 36304335 PMCID: PMC9580958 DOI: 10.3389/fbinf.2022.1019597] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Accepted: 09/20/2022] [Indexed: 11/07/2022] Open
Abstract
Predictions for millions of protein three-dimensional structures are only a few clicks away since the release of AlphaFold2 results for UniProt. However, many proteins have so-called intrinsically disordered regions (IDRs) that do not adopt unique structures in isolation. These IDRs are associated with several diseases, including Alzheimer’s Disease. We showed that three recent disorder measures of AlphaFold2 predictions (pLDDT, “experimentally resolved” prediction and “relative solvent accessibility”) correlated to some extent with IDRs. However, expert methods predict IDRs more reliably by combining complex machine learning models with expert-crafted input features and evolutionary information from multiple sequence alignments (MSAs). MSAs are not always available, especially for IDRs, and are computationally expensive to generate, limiting the scalability of the associated tools. Here, we present the novel method SETH that predicts residue disorder from embeddings generated by the protein Language Model ProtT5, which explicitly only uses single sequences as input. Thereby, our method, relying on a relatively shallow convolutional neural network, outperformed much more complex solutions while being much faster, allowing to create predictions for the human proteome in about 1 hour on a consumer-grade PC with one NVIDIA GeForce RTX 3060. Trained on a continuous disorder scale (CheZOD scores), our method captured subtle variations in disorder, thereby providing important information beyond the binary classification of most methods. High performance paired with speed revealed that SETH’s nuanced disorder predictions for entire proteomes capture aspects of the evolution of organisms. Additionally, SETH could also be used to filter out regions or proteins with probable low-quality AlphaFold2 3D structures to prioritize running the compute-intensive predictions for large data sets. SETH is freely publicly available at: https://github.com/Rostlab/SETH.
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Affiliation(s)
- Dagmar Ilzhöfer
- Faculty of Informatics, TUM (Technical University of Munich), Munich, Germany
| | - Michael Heinzinger
- Faculty of Informatics, TUM (Technical University of Munich), Munich, Germany,Center of Doctoral Studies in Informatics and Its Applications (CeDoSIA), TUM Graduate School, Garching, Germany,*Correspondence: Michael Heinzinger,
| | - Burkhard Rost
- Faculty of Informatics, TUM (Technical University of Munich), Munich, Germany,Institute for Advanced Study (TUM-IAS), TUM (Technical University of Munich), Garching, Germany,TUM School of Life Sciences Weihenstephan (WZW), TUM (Technical University of Munich), Freising, Germany
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32
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Handa T, Kundu D, Dubey VK. Perspectives on evolutionary and functional importance of intrinsically disordered proteins. Int J Biol Macromol 2022; 224:243-255. [DOI: 10.1016/j.ijbiomac.2022.10.120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 10/08/2022] [Accepted: 10/10/2022] [Indexed: 11/05/2022]
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33
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Conformational buffering underlies functional selection in intrinsically disordered protein regions. Nat Struct Mol Biol 2022; 29:781-790. [PMID: 35948766 DOI: 10.1038/s41594-022-00811-w] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 06/23/2022] [Indexed: 02/02/2023]
Abstract
Many disordered proteins conserve essential functions in the face of extensive sequence variation, making it challenging to identify the mechanisms responsible for functional selection. Here we identify the molecular mechanism of functional selection for the disordered adenovirus early gene 1A (E1A) protein. E1A competes with host factors to bind the retinoblastoma (Rb) protein, subverting cell cycle regulation. We show that two binding motifs tethered by a hypervariable disordered linker drive picomolar affinity Rb binding and host factor displacement. Compensatory changes in amino acid sequence composition and sequence length lead to conservation of optimal tethering across a large family of E1A linkers. We refer to this compensatory mechanism as conformational buffering. We also detect coevolution of the motifs and linker, which can preserve or eliminate the tethering mechanism. Conformational buffering and motif-linker coevolution explain robust functional encoding within hypervariable disordered linkers and could underlie functional selection of many disordered protein regions.
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34
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Krasinska L, Fisher D. A Mechanistic Model for Cell Cycle Control in Which CDKs Act as Switches of Disordered Protein Phase Separation. Cells 2022; 11:cells11142189. [PMID: 35883632 PMCID: PMC9321858 DOI: 10.3390/cells11142189] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 07/05/2022] [Accepted: 07/06/2022] [Indexed: 12/30/2022] Open
Abstract
Cyclin-dependent kinases (CDKs) are presumed to control the cell cycle by phosphorylating a large number of proteins involved in S-phase and mitosis, two mechanistically disparate biological processes. While the traditional qualitative model of CDK-mediated cell cycle control relies on differences in inherent substrate specificity between distinct CDK-cyclin complexes, they are largely dispensable according to the opposing quantitative model, which states that changes in the overall CDK activity level promote orderly progression through S-phase and mitosis. However, a mechanistic explanation for how such an activity can simultaneously regulate many distinct proteins is lacking. New evidence suggests that the CDK-dependent phosphorylation of ostensibly very diverse proteins might be achieved due to underlying similarity of phosphorylation sites and of the biochemical effects of their phosphorylation: they are preferentially located within intrinsically disordered regions of proteins that are components of membraneless organelles, and they regulate phase separation. Here, we review this evidence and suggest a mechanism for how a single enzyme’s activity can generate the dynamics required to remodel the cell at mitosis.
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35
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Deciphering the Biological Enigma-Genomic Evolution Underlying Anhydrobiosis in the Phylum Tardigrada and the Chironomid Polypedilum vanderplanki. INSECTS 2022; 13:insects13060557. [PMID: 35735894 PMCID: PMC9224920 DOI: 10.3390/insects13060557] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 06/13/2022] [Accepted: 06/17/2022] [Indexed: 02/04/2023]
Abstract
Anhydrobiosis, an ametabolic dehydrated state triggered by water loss, is observed in several invertebrate lineages. Anhydrobiotes revive when rehydrated, and seem not to suffer the ultimately lethal cell damage that results from severe loss of water in other organisms. Here, we review the biochemical and genomic evidence that has revealed the protectant molecules, repair systems, and maintenance pathways associated with anhydrobiosis. We then introduce two lineages in which anhydrobiosis has evolved independently: Tardigrada, where anhydrobiosis characterizes many species within the phylum, and the genus Polypedilum, where anhydrobiosis occurs in only two species. Finally, we discuss the complexity of the evolution of anhydrobiosis within invertebrates based on current knowledge, and propose perspectives to enhance the understanding of anhydrobiosis.
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36
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Ahmed SS, Rifat ZT, Lohia R, Campbell AJ, Dunker AK, Rahman MS, Iqbal S. Characterization of intrinsically disordered regions in proteins informed by human genetic diversity. PLoS Comput Biol 2022; 18:e1009911. [PMID: 35275927 PMCID: PMC8942211 DOI: 10.1371/journal.pcbi.1009911] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 03/23/2022] [Accepted: 02/10/2022] [Indexed: 01/21/2023] Open
Abstract
All proteomes contain both proteins and polypeptide segments that don’t form a defined three-dimensional structure yet are biologically active—called intrinsically disordered proteins and regions (IDPs and IDRs). Most of these IDPs/IDRs lack useful functional annotation limiting our understanding of their importance for organism fitness. Here we characterized IDRs using protein sequence annotations of functional sites and regions available in the UniProt knowledgebase (“UniProt features”: active site, ligand-binding pocket, regions mediating protein-protein interactions, etc.). By measuring the statistical enrichment of twenty-five UniProt features in 981 IDRs of 561 human proteins, we identified eight features that are commonly located in IDRs. We then collected the genetic variant data from the general population and patient-based databases and evaluated the prevalence of population and pathogenic variations in IDPs/IDRs. We observed that some IDRs tolerate 2 to 12-times more single amino acid-substituting missense mutations than synonymous changes in the general population. However, we also found that 37% of all germline pathogenic mutations are located in disordered regions of 96 proteins. Based on the observed-to-expected frequency of mutations, we categorized 34 IDRs in 20 proteins (DDX3X, KIT, RB1, etc.) as intolerant to mutation. Finally, using statistical analysis and a machine learning approach, we demonstrate that mutation-intolerant IDRs carry a distinct signature of functional features. Our study presents a novel approach to assign functional importance to IDRs by leveraging the wealth of available genetic data, which will aid in a deeper understating of the role of IDRs in biological processes and disease mechanisms.
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Affiliation(s)
- Shehab S. Ahmed
- Department of Computer Science and Engineering, Bangladesh University of Engineering and Technology, ECE Building, West Palashi, Dhaka-1205, Bangladesh
| | - Zaara T. Rifat
- Department of Computer Science and Engineering, Bangladesh University of Engineering and Technology, ECE Building, West Palashi, Dhaka-1205, Bangladesh
| | - Ruchi Lohia
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
| | - Arthur J. Campbell
- Center for the Development of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | - A. Keith Dunker
- Center for Computational Biology and Bioinformatics, Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, Indiana, United States of America
| | - M. Sohel Rahman
- Department of Computer Science and Engineering, Bangladesh University of Engineering and Technology, ECE Building, West Palashi, Dhaka-1205, Bangladesh
- * E-mail: (MSR); (SI)
| | - Sumaiya Iqbal
- Center for the Development of Therapeutics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
- Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
- Analytic and Translational Genetics Unit, Massachusetts General Hospital, Boston, Massachusetts, United States of America
- * E-mail: (MSR); (SI)
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37
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Moreira F, Arenas M, Videira A, Pereira F. Evolutionary History of TOPIIA Topoisomerases in Animals. J Mol Evol 2022; 90:149-165. [PMID: 35165762 DOI: 10.1007/s00239-022-10048-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 01/26/2022] [Indexed: 01/15/2023]
Abstract
TOPIIA topoisomerases are required for the regulation of DNA topology by DNA cleavage and re-ligation and are important targets of antibiotic and anticancer agents. Humans possess two TOPIIA paralogue genes (TOP2A and TOP2B) with high sequence and structural similarity but distinct cellular functions. Despite their functional and clinical relevance, the evolutionary history of TOPIIA is still poorly understood. Here we show that TOPIIA is highly conserved in Metazoa. We also found that TOPIIA paralogues from jawed and jawless vertebrates had different origins related with tetraploidization events. After duplication, TOP2B evolved under a stronger purifying selection than TOP2A, perhaps promoted by the more specialized role of TOP2B in postmitotic cells. We also detected genetic signatures of positive selection in the highly variable C-terminal domain (CTD), possibly associated with adaptation to cellular interactions. By comparing TOPIIA from modern and archaic humans, we found two amino acid substitutions in the TOP2A CTD, suggesting that TOP2A may have contributed to the evolution of present-day humans, as proposed for other cell cycle-related genes. Finally, we identified six residues conferring resistance to chemotherapy differing between TOP2A and TOP2B. These six residues could be targets for the development of TOP2A-specific inhibitors that would avoid the side effects caused by inhibiting TOP2B. Altogether, our findings clarify the origin, diversification and selection pressures governing the evolution of animal TOPIIA.
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Affiliation(s)
- Filipa Moreira
- Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Terminal de Cruzeiros do Porto de Leixões, Av. General Norton de Matos s/n, 4450-208, Matosinhos, Portugal
- ICBAS - Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Rua Jorge de Viterbo Ferreira 228, 4050-313, Porto, Portugal
| | - Miguel Arenas
- Department of Biochemistry, Genetics and Immunology, University of Vigo, 36310, Vigo, Spain
- CINBIO, Universidade de Vigo, 36310, Vigo, Spain
- Galicia Sur Health Research Institute (IIS Galicia Sur), 36310, Vigo, Spain
| | - Arnaldo Videira
- ICBAS - Instituto de Ciências Biomédicas de Abel Salazar, Universidade do Porto, Rua Jorge de Viterbo Ferreira 228, 4050-313, Porto, Portugal
- IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
- i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Porto, Portugal
| | - Filipe Pereira
- IDENTIFICA Genetic Testing, Rua Simão Bolívar 259 3º Dir Tras, 4470-214, Maia, Portugal.
- Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Calçada Martim de Freitas, 3000-456, Coimbra, Portugal.
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38
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Lestari B, Naito S, Endo A, Nishihara H, Kato A, Watanabe E, Denda K, Komada M, Fukushima T. Placental mammals acquired functional sequences in NRK for regulating the CK2-PTEN-AKT pathway and placental cell proliferation. Mol Biol Evol 2022; 39:6499274. [PMID: 34999820 PMCID: PMC8857918 DOI: 10.1093/molbev/msab371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The molecular evolution processes underlying the acquisition of the placenta in eutherian ancestors are not fully understood. Mouse NCK-interacting kinase (NIK)-related kinase (NRK) is expressed highly in the placenta and plays a role in preventing placental hyperplasia. Here, we show the molecular evolution of NRK, which confers its function for inhibiting placental cell proliferation. Comparative genome analysis identified NRK orthologs across vertebrates, which share the kinase and citron homology (CNH) domains. Evolutionary analysis revealed that NRK underwent extensive amino acid substitutions in the ancestor of placental mammals and has been since conserved. Biochemical analysis of mouse NRK revealed that the CNH domain binds to phospholipids, and a region in NRK binds to and inhibits casein kinase-2 (CK2), which we named the CK2-inhibitory region (CIR). Cell culture experiments suggest the following: 1) Mouse NRK is localized at the plasma membrane via the CNH domain, where the CIR inhibits CK2. 2) This mitigates CK2-dependent phosphorylation and inhibition of PTEN and 3) leads to the inhibition of AKT signaling and cell proliferation. Nrk deficiency increased phosphorylation levels of PTEN and AKT in mouse placenta, supporting our hypothesis. Unlike mouse NRK, chicken NRK did not bind to phospholipids and CK2, decrease phosphorylation of AKT, or inhibit cell proliferation. Both the CNH domain and CIR have evolved under purifying selection in placental mammals. Taken together, our study suggests that placental mammals acquired the phospholipid-binding CNH domain and CIR in NRK for regulating the CK2–PTEN–AKT pathway and placental cell proliferation.
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Affiliation(s)
- Beni Lestari
- School of Life Science and Technology, Tokyo Institute of Technology, Japan
| | - Satomi Naito
- School of Life Science and Technology, Tokyo Institute of Technology, Japan
| | - Akinori Endo
- Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, Japan
| | - Hidenori Nishihara
- School of Life Science and Technology, Tokyo Institute of Technology, Japan
| | - Akira Kato
- School of Life Science and Technology, Tokyo Institute of Technology, Japan
| | - Erika Watanabe
- School of Life Science and Technology, Tokyo Institute of Technology, Japan
| | - Kimitoshi Denda
- School of Life Science and Technology, Tokyo Institute of Technology, Japan
| | - Masayuki Komada
- School of Life Science and Technology, Tokyo Institute of Technology, Japan.,Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, Japan
| | - Toshiaki Fukushima
- School of Life Science and Technology, Tokyo Institute of Technology, Japan.,Cell Biology Center, Institute of Innovative Research, Tokyo Institute of Technology, Japan
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39
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Chin AF, Zheng Y, Hilser VJ. Phylogenetic convergence of phase separation and mitotic function in the disordered protein BuGZ. Protein Sci 2022; 31:822-834. [PMID: 34984754 DOI: 10.1002/pro.4270] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 12/29/2021] [Accepted: 12/30/2021] [Indexed: 11/05/2022]
Abstract
Intrinsically disordered proteins (IDPs) effect biological function despite their sequence-encoded lack of preference for stable three-dimensional structure. Among their many functions, IDPs form membraneless cellular compartments through liquid-liquid phase separation (LLPS), also termed biomolecular condensation. The extent to which LLPS has been evolutionarily selected remains largely unknown, as the complexities of IDP evolution hamper progress. Unlike structured proteins, rapid sequence divergence typical of IDPs confounds inference of their biophysical or biological functions from comparative sequence analyses. Here, we leverage mitosis as a universal eukaryotic feature to interrogate condensate evolutionary history. We observe that evolution has conserved the ability for six homologs of the mitotic IDP BuGZ to undergo LLPS and to serve the same mitotic function, despite low sequence conservation. We also observe that cellular context may tune LLPS. The phylogenetic correlation of LLPS and mitotic function in one protein raises the possibility of an ancient evolutionary interplay between LLPS and biological function, dating back at least 1.6 billion years to the last common ancestor of plants and animals. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Alexander F Chin
- Department of Biology, Johns Hopkins University, Baltimore, Maryland, USA
| | - Yixian Zheng
- Department of Biology, Johns Hopkins University, Baltimore, Maryland, USA.,Department of Embryology, Carnegie Institution for Science, 3520 San Martin Drive, Baltimore, Maryland, USA
| | - Vincent J Hilser
- Department of Biology, Johns Hopkins University, Baltimore, Maryland, USA.,T.C. Jenkins Department of Biophysics, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland, USA
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40
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Schultz CJ, Wu Y, Baumann U. A targeted bioinformatics approach identifies highly variable cell surface proteins that are unique to Glomeromycotina. MYCORRHIZA 2022; 32:45-66. [PMID: 35031894 PMCID: PMC8786786 DOI: 10.1007/s00572-021-01066-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 12/24/2021] [Indexed: 06/14/2023]
Abstract
Diversity in arbuscular mycorrhizal fungi (AMF) contributes to biodiversity and resilience in natural environments and healthy agricultural systems. Functional complementarity exists among species of AMF in symbiosis with their plant hosts, but the molecular basis of this is not known. We hypothesise this is in part due to the difficulties that current sequence assembly methodologies have assembling sequences for intrinsically disordered proteins (IDPs) due to their low sequence complexity. IDPs are potential candidates for functional complementarity because they often exist as extended (non-globular) proteins providing additional amino acids for molecular interactions. Rhizophagus irregularis arabinogalactan-protein-like proteins (AGLs) are small secreted IDPs with no known orthologues in AMF or other fungi. We developed a targeted bioinformatics approach to identify highly variable AGLs/IDPs in RNA-sequence datasets. The approach includes a modified multiple k-mer assembly approach (Oases) to identify candidate sequences, followed by targeted sequence capture and assembly (mirabait-mira). All AMF species analysed, including the ancestral family Paraglomeraceae, have small families of proteins rich in disorder promoting amino acids such as proline and glycine, or glycine and asparagine. Glycine- and asparagine-rich proteins also were found in Geosiphon pyriformis (an obligate symbiont of a cyanobacterium), from the same subphylum (Glomeromycotina) as AMF. The sequence diversity of AGLs likely translates to functional diversity, based on predicted physical properties of tandem repeats (elastic, amyloid, or interchangeable) and their broad pI ranges. We envisage that AGLs/IDPs could contribute to functional complementarity in AMF through processes such as self-recognition, retention of nutrients, soil stability, and water movement.
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Affiliation(s)
- Carolyn J Schultz
- School of Agriculture, Food, and Wine, Waite Research Institute, University of Adelaide, Adelaide, SA, Australia.
| | - Yue Wu
- School of Agriculture, Food, and Wine, Waite Research Institute, University of Adelaide, Adelaide, SA, Australia
| | - Ute Baumann
- School of Agriculture, Food, and Wine, Waite Research Institute, University of Adelaide, Adelaide, SA, Australia
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41
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Tamburrini KC, Pesce G, Nilsson J, Gondelaud F, Kajava AV, Berrin JG, Longhi S. Predicting Protein Conformational Disorder and Disordered Binding Sites. Methods Mol Biol 2022; 2449:95-147. [PMID: 35507260 DOI: 10.1007/978-1-0716-2095-3_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
In the last two decades it has become increasingly evident that a large number of proteins adopt either a fully or a partially disordered conformation. Intrinsically disordered proteins are ubiquitous proteins that fulfill essential biological functions while lacking a stable 3D structure. Their conformational heterogeneity is encoded by the amino acid sequence, thereby allowing intrinsically disordered proteins or regions to be recognized based on their sequence properties. The identification of disordered regions facilitates the functional annotation of proteins and is instrumental for delineating boundaries of protein domains amenable to crystallization. This chapter focuses on the methods currently employed for predicting protein disorder and identifying intrinsically disordered binding sites.
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Affiliation(s)
- Ketty C Tamburrini
- Aix Marseille Univ, CNRS, Architecture et Fonction des Macromolécules Biologiques, AFMB, UMR 7257, Marseille, France
- INRAE, Aix Marseille Univ, Biodiversité et Biotechnologie Fongiques (BBF), UMR 1163, Marseille, France
| | - Giulia Pesce
- Aix Marseille Univ, CNRS, Architecture et Fonction des Macromolécules Biologiques, AFMB, UMR 7257, Marseille, France
| | - Juliet Nilsson
- Aix Marseille Univ, CNRS, Architecture et Fonction des Macromolécules Biologiques, AFMB, UMR 7257, Marseille, France
| | - Frank Gondelaud
- Aix Marseille Univ, CNRS, Architecture et Fonction des Macromolécules Biologiques, AFMB, UMR 7257, Marseille, France
| | - Andrey V Kajava
- Centre de Recherche en Biologie cellulaire de Montpellier, UMR 5237, CNRS, Université Montpellier, Montpellier, France
| | - Jean-Guy Berrin
- INRAE, Aix Marseille Univ, Biodiversité et Biotechnologie Fongiques (BBF), UMR 1163, Marseille, France
| | - Sonia Longhi
- Aix Marseille Univ, CNRS, Architecture et Fonction des Macromolécules Biologiques, AFMB, UMR 7257, Marseille, France.
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42
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Conformational dynamics promotes disordered regions from function-dispensable to essential in evolved site-specific DNA recombinases. Comput Struct Biotechnol J 2022; 20:989-1001. [PMID: 35242289 PMCID: PMC8860914 DOI: 10.1016/j.csbj.2022.01.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 01/11/2022] [Accepted: 01/11/2022] [Indexed: 12/11/2022] Open
Abstract
New functional regions emerging in evolution of DNA site-specific recombinase tails. Transient structural nucleation promotes function-dispensable regions to essential. Molecular dynamics reveals conformational diversity and its functional implications. Evolved disordered molecular mechanisms of N-term tails for protein stability. Structural disorder-based link between protein evolution, stability and function.
Protein intrinsically disordered regions (IDRs) play pivotal roles in molecular recognition and regulatory processes through structural disorder-to-order transitions. To understand and exploit the distinctive functional implications of IDRs and to unravel the underlying molecular mechanisms, structural disorder-to-function relationships need to be deciphered. The DNA site-specific recombinase system Cre/loxP represents an attractive model to investigate functional molecular mechanisms of IDRs. Cre contains a functionally dispensable disordered N-terminal tail, which becomes indispensable in the evolved Tre/loxLTR recombinase system. The difficulty to experimentally obtain structural information about this tail has so far precluded any mechanistic study on its involvement in DNA recombination. Here, we use in vitro and in silico evolution data, conformational dynamics, AI-based folding simulations, thermodynamic stability calculations, mutagenesis and DNA recombination assays to investigate how evolution and the dynamic behavior of this IDR may determine distinct functional properties. Our studies suggest that partial conformational order in the N-terminal tail of Tre recombinase and its packing to a conserved hydrophobic surface on the protein provide thermodynamic stability. Based on our results, we propose a link between protein stability and function, offering new plausible atom-detailed mechanistic insights into disorder-function relationships. Our work highlights the potential of N-terminal tails to be exploited for regulation of the activity of Cre-like tyrosine-type SSRs, which merits future investigations and could be of relevance in future rational engineering for their use in biotechnology and genomic medicine.
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Flanking Disorder of the Folded αα-Hub Domain from Radical Induced Cell Death1 Affects Transcription Factor Binding by Ensemble Redistribution. J Mol Biol 2021; 433:167320. [PMID: 34687712 DOI: 10.1016/j.jmb.2021.167320] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Revised: 09/28/2021] [Accepted: 10/13/2021] [Indexed: 11/22/2022]
Abstract
Protein intrinsic disorder is essential for organization of transcription regulatory interactomes. In these interactomes, the majority of transcription factors as well as their interaction partners have co-existing order and disorder. Yet, little attention has been paid to their interplay. Here, we investigate how order is affected by flanking disorder in the folded αα-hub domain RST from Radical-Induced Cell Death1 (RCD1), central in a large interactome of transcription factors. We show that the intrinsically disordered C-terminal tail of RCD1-RST shifts its conformational ensemble towards a pseudo-bound state through weak interactions with the ligand-binding pocket. An unfolded excited state is also accessible on the ms timescale independent of surrounding disordered regions, but its population is lowered by 50% in their presence. Flanking disorder additionally lowers transcription factor binding-affinity without affecting the dissociation rate constant, in accordance with similar bound-states assessed by NMR. The extensive dynamics of the RCD1-RST domain, modulated by flanking disorder, is suggestive of its adaptation to many different transcription factor ligands. The study illustrates how disordered flanking regions can tune fold and function through ensemble redistribution and is of relevance to modular proteins in general, many of which play key roles in regulation of genes.
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Seera S, Nagarajaram HA. Effect of Disease Causing Missense Mutations on Intrinsically Disordered Regions in Proteins. Protein Pept Lett 2021; 29:254-267. [PMID: 34825861 DOI: 10.2174/0929866528666211126161200] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 10/01/2021] [Accepted: 10/01/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND It is well known that disease-causing missense mutations (DCMMs) reduce the structural stability/integrity of the proteins with well-defined 3D structures, thereby impacting their molecular functions. However, it is not known in what way DCMMs affect the intrinsically disordered proteins (IDPs) that do not adopt well defined stable 3D structures. METHODS In order to investigate how DCMMs may impact intrinsically disordered regions (IDRs) in proteins, we undertook Molecular Dynamics (MD) based studies on three different examples of functionally important IDRs with known DCMMs. Our studies revealed that the functional impact of DCMMs is in reducing the conformational heterogeneity of IDRs, which is intrinsic and quintessential for their multi-faceted cellular roles. RESULTS These results are reinforced by energy landscapes of the wildtype and mutant IDRs where the former is characterized by many local minima separated by low barriers, whereas the latter are characterized by one global minimum and several local minima separated by high energy barriers. Our MD based studies also indicate that DCMMs stabilize very few structural possibilities of IDRs either by the newly formed interactions induced by the substituted side chains or by means of restricted or increased flexibilities of the backbone conformations at the mutation sites. CONCLUSION Furthermore, the structural possibilities stabilized by DCMMs do not support the native functional roles of the IDRs, thereby leading to disease conditions.
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Affiliation(s)
| | - Hampapathalu A Nagarajaram
- Laboratory of Computational Biology, Department of Systems and Computational Biology, School of Life Sciences, University of Hyderabad, Hyderabad, India
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Vedelek B, Kovács Á, Boros IM. Evolutionary mode for the functional preservation of fast-evolving Drosophila telomere capping proteins. Open Biol 2021; 11:210261. [PMID: 34784790 PMCID: PMC8596017 DOI: 10.1098/rsob.210261] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
DNA end protection is fundamental for the long-term preservation of the genome. In vertebrates the Shelterin protein complex protects telomeric DNA ends, thereby contributing to the maintenance of genome integrity. In the Drosophila genus, this function is thought to be performed by the Terminin complex, an assembly of fast-evolving subunits. Considering that DNA end protection is fundamental for successful genome replication, the accelerated evolution of Terminin subunits is counterintuitive, as conservation is supposed to maintain the assembly and concerted function of the interacting partners. This problem extends over Drosophila telomere biology and provides insight into the evolution of protein assemblies. In order to learn more about the mechanistic details of this phenomenon we have investigated the intra- and interspecies assemblies of Verrocchio and Modigliani, two Terminin subunits using in vitro assays. Based on our results and on homology-based three-dimensional models for Ver and Moi, we conclude that both proteins contain Ob-fold and contribute to the ssDNA binding of the Terminin complex. We propose that the preservation of Ver function is achieved by conservation of specific amino acids responsible for folding or localized in interacting surfaces. We also provide here the first evidence on Moi DNA binding.
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Affiliation(s)
- Balázs Vedelek
- Department of Biochemistry and Molecular Biology, University of Szeged, Szeged, Hungary,Institute of Biochemistry, Biological Research Centre, Szeged, Hungary
| | - Ákos Kovács
- Department of Biochemistry and Molecular Biology, University of Szeged, Szeged, Hungary
| | - Imre M. Boros
- Department of Biochemistry and Molecular Biology, University of Szeged, Szeged, Hungary,Institute of Biochemistry, Biological Research Centre, Szeged, Hungary
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McMenamin AJ, Brutscher LM, Daughenbaugh KF, Flenniken ML. The Honey Bee Gene Bee Antiviral Protein-1 Is a Taxonomically Restricted Antiviral Immune Gene. FRONTIERS IN INSECT SCIENCE 2021; 1:749781. [PMID: 38468887 PMCID: PMC10926557 DOI: 10.3389/finsc.2021.749781] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 09/20/2021] [Indexed: 03/13/2024]
Abstract
Insects have evolved a wide range of strategies to combat invading pathogens, including viruses. Genes that encode proteins involved in immune responses often evolve under positive selection due to their co-evolution with pathogens. Insect antiviral defense includes the RNA interference (RNAi) mechanism, which is triggered by recognition of non-self, virally produced, double-stranded RNAs. Indeed, insect RNAi genes (e.g., dicer and argonaute-2) are under high selective pressure. Honey bees (Apis mellifera) are eusocial insects that respond to viral infections via both sequence specific RNAi and a non-sequence specific dsRNA triggered pathway, which is less well-characterized. A transcriptome-level study of virus-infected and/or dsRNA-treated honey bees revealed increased expression of a novel antiviral gene, GenBank: MF116383, and in vivo experiments confirmed its antiviral function. Due to in silico annotation and sequence similarity, MF116383 was originally annotated as a probable cyclin-dependent serine/threonine-protein kinase. In this study, we confirmed that MF116383 limits virus infection, and carried out further bioinformatic and phylogenetic analyses to better characterize this important gene-which we renamed bee antiviral protein-1 (bap1). Phylogenetic analysis revealed that bap1 is taxonomically restricted to Hymenoptera and Blatella germanica (the German cockroach) and that the majority of bap1 amino acids are evolving under neutral selection. This is in-line with the results from structural prediction tools that indicate Bap1 is a highly disordered protein, which likely has relaxed structural constraints. Assessment of honey bee gene expression using a weighted gene correlation network analysis revealed that bap1 expression was highly correlated with several immune genes-most notably argonaute-2. The coexpression of bap1 and argonaute-2 was confirmed in an independent dataset that accounted for the effect of virus abundance. Together, these data demonstrate that bap1 is a taxonomically restricted, rapidly evolving antiviral immune gene. Future work will determine the role of bap1 in limiting replication of other viruses and examine the signal cascade responsible for regulating the expression of bap1 and other honey bee antiviral defense genes, including coexpressed ago-2, and determine whether the virus limiting function of bap1 acts in parallel or in tandem with RNAi.
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Affiliation(s)
- Alexander J. McMenamin
- Department of Plant Sciences and Plant Pathology, Montana State University, Bozeman, MT, United States
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, United States
- Pollinator Health Center, Montana State University, Bozeman, MT, United States
| | - Laura M. Brutscher
- Pollinator Health Center, Montana State University, Bozeman, MT, United States
| | - Katie F. Daughenbaugh
- Department of Plant Sciences and Plant Pathology, Montana State University, Bozeman, MT, United States
- Pollinator Health Center, Montana State University, Bozeman, MT, United States
| | - Michelle L. Flenniken
- Department of Plant Sciences and Plant Pathology, Montana State University, Bozeman, MT, United States
- Department of Microbiology and Immunology, Montana State University, Bozeman, MT, United States
- Pollinator Health Center, Montana State University, Bozeman, MT, United States
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Pajkos M, Dosztányi Z. Functions of intrinsically disordered proteins through evolutionary lenses. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2021; 183:45-74. [PMID: 34656334 DOI: 10.1016/bs.pmbts.2021.06.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Protein sequences are the result of an evolutionary process that involves the balancing act of experimenting with novel mutations and selecting out those that have an undesirable functional outcome. In the case of globular proteins, the function relies on a well-defined conformation, therefore, there is a strong evolutionary pressure to preserve the structure. However, different evolutionary rules might apply for the group of intrinsically disordered regions and proteins (IDR/IDPs) that exist as an ensemble of fluctuating conformations. The function of IDRs can directly originate from their disordered state or arise through different types of molecular recognition processes. There is an amazing variety of ways IDRs can carry out their functions, and this is also reflected in their evolutionary properties. In this chapter we give an overview of the different types of evolutionary behavior of disordered proteins and associated functions in normal and disease settings.
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Affiliation(s)
- Mátyás Pajkos
- Department of Biochemistry, ELTE Eötvös Loránd University, Budapest, Hungary
| | - Zsuzsanna Dosztányi
- Department of Biochemistry, ELTE Eötvös Loránd University, Budapest, Hungary.
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48
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Ruff KM, Pappu RV. AlphaFold and Implications for Intrinsically Disordered Proteins. J Mol Biol 2021; 433:167208. [PMID: 34418423 DOI: 10.1016/j.jmb.2021.167208] [Citation(s) in RCA: 223] [Impact Index Per Article: 74.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 08/11/2021] [Accepted: 08/12/2021] [Indexed: 10/20/2022]
Abstract
Accurate predictions of the three-dimensional structures of proteins from their amino acid sequences have come of age. AlphaFold, a deep learning-based approach to protein structure prediction, shows remarkable success in independent assessments of prediction accuracy. A significant epoch in structural bioinformatics was the structural annotation of over 98% of protein sequences in the human proteome. Interestingly, many predictions feature regions of very low confidence, and these regions largely overlap with intrinsically disordered regions (IDRs). That over 30% of regions within the proteome are disordered is congruent with estimates that have been made over the past two decades, as intense efforts have been undertaken to generalize the structure-function paradigm to include the importance of conformational heterogeneity and dynamics. With structural annotations from AlphaFold in hand, there is the temptation to draw inferences regarding the "structures" of IDRs and their interactomes. Here, we offer a cautionary note regarding the misinterpretations that might ensue and highlight efforts that provide concrete understanding of sequence-ensemble-function relationships of IDRs. This perspective is intended to emphasize the importance of IDRs in sequence-function relationships (SERs) and to highlight how one might go about extracting quantitative SERs to make sense of how IDRs function.
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Affiliation(s)
- Kiersten M Ruff
- Department of Biomedical Engineering and Center for Science & Engineering of Living Systems (CSELS), Washington University in St. Louis, Campus Box 1097, St. Louis, MO 63130, USA
| | - Rohit V Pappu
- Department of Biomedical Engineering and Center for Science & Engineering of Living Systems (CSELS), Washington University in St. Louis, Campus Box 1097, St. Louis, MO 63130, USA.
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Remnant L, Kochanova NY, Reid C, Cisneros-Soberanis F, Earnshaw WC. The intrinsically disorderly story of Ki-67. Open Biol 2021; 11:210120. [PMID: 34375547 PMCID: PMC8354752 DOI: 10.1098/rsob.210120] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 07/13/2021] [Indexed: 01/14/2023] Open
Abstract
Ki-67 is one of the most famous marker proteins used by histologists to identify proliferating cells. Indeed, over 30 000 articles referring to Ki-67 are listed on PubMed. Here, we review some of the current literature regarding the protein. Despite its clinical importance, our knowledge of the molecular biology and biochemistry of Ki-67 is far from complete, and its exact molecular function(s) remain enigmatic. Furthermore, reports describing Ki-67 function are often contradictory, and it has only recently become clear that this proliferation marker is itself dispensable for cell proliferation. We discuss the unusual organization of the protein and its mRNA and how they relate to various models for its function. In particular, we focus on ways in which the intrinsically disordered structure of Ki-67 might aid in the assembly of the still-mysterious mitotic chromosome periphery compartment by controlling liquid-liquid phase separation of nucleolar proteins and RNAs.
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Affiliation(s)
- Lucy Remnant
- Wellcome Centre for Cell Biology, University of Edinburgh, ICB, Michael Swann Building, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Natalia Y. Kochanova
- Wellcome Centre for Cell Biology, University of Edinburgh, ICB, Michael Swann Building, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Caitlin Reid
- Wellcome Centre for Cell Biology, University of Edinburgh, ICB, Michael Swann Building, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - Fernanda Cisneros-Soberanis
- Wellcome Centre for Cell Biology, University of Edinburgh, ICB, Michael Swann Building, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
| | - William C. Earnshaw
- Wellcome Centre for Cell Biology, University of Edinburgh, ICB, Michael Swann Building, King's Buildings, Max Born Crescent, Edinburgh EH9 3BF, UK
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50
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Ruidiaz SF, Dreier JE, Hartmann-Petersen R, Kragelund BB. The disordered PCI-binding human proteins CSNAP and DSS1 have diverged in structure and function. Protein Sci 2021; 30:2069-2082. [PMID: 34272906 PMCID: PMC8442969 DOI: 10.1002/pro.4159] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 07/13/2021] [Accepted: 07/15/2021] [Indexed: 12/30/2022]
Abstract
Intrinsically disordered proteins (IDPs) regularly constitute components of larger protein assemblies contributing to architectural stability. Two small, highly acidic IDPs have been linked to the so-called PCI complexes carrying PCI-domain subunits, including the proteasome lid and the COP9 signalosome. These two IDPs, DSS1 and CSNAP, have been proposed to have similar structural propensities and functions, but they display differences in their interactions and interactome sizes. Here we characterized the structural properties of human DSS1 and CSNAP at the residue level using NMR spectroscopy and probed their propensities to bind ubiquitin. We find that distinct structural features present in DSS1 are completely absent in CSNAP, and vice versa, with lack of relevant ubiquitin binding to CSNAP, suggesting the two proteins to have diverged in both structure and function. Our work additionally highlights that different local features of seemingly similar IDPs, even subtle sequence variance, may endow them with different functional traits. Such traits may underlie their potential to engage in multiple interactions thereby impacting their interactome sizes.
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Affiliation(s)
- Sarah F Ruidiaz
- Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, Copenhagen N, Denmark.,REPIN, Department of Biology, University of Copenhagen, Copenhagen N, Denmark
| | - Jesper E Dreier
- Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, Copenhagen N, Denmark.,REPIN, Department of Biology, University of Copenhagen, Copenhagen N, Denmark
| | - Rasmus Hartmann-Petersen
- REPIN, Department of Biology, University of Copenhagen, Copenhagen N, Denmark.,The Linderstrøm Lang Centre for Protein Science, Department of Biology, University of Copenhagen, Copenhagen N, Denmark
| | - Birthe B Kragelund
- Structural Biology and NMR Laboratory, Department of Biology, University of Copenhagen, Copenhagen N, Denmark.,REPIN, Department of Biology, University of Copenhagen, Copenhagen N, Denmark
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