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Chandrasekaran SN, Das J, Dokholyan NV, Carter CW. Microcalorimetry reveals multi-state thermal denaturation of G. stearothermophilus tryptophanyl-tRNA synthetase. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2023; 10:044301. [PMID: 37476003 PMCID: PMC10356175 DOI: 10.1063/4.0000181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 06/21/2023] [Indexed: 07/22/2023]
Abstract
Mechanistic studies of Geobacillus stearothermophilus tryptophanyl-tRNA synthetase (TrpRS) afford an unusually detailed description-the escapement mechanism-for the distinct steps coupling catalysis to domain motion, efficiently converting the free energy of ATP hydrolysis into biologically useful alternative forms of information and work. Further elucidation of the escapement mechanism requires understanding thermodynamic linkages between domain configuration and conformational stability. To that end, we compare experimental thermal melting of fully liganded and apo TrpRS with a computational simulation of the melting of its fully liganded form. The simulation also provides important structural cameos at successively higher temperatures, enabling more confident interpretation. Experimental and simulated melting both proceed through a succession of three transitions at successively higher temperature. The low-temperature transition occurs at approximately the growth temperature of the organism and so may be functionally relevant but remains too subtle to characterize structurally. Structural metrics from the simulation imply that the two higher-temperature transitions entail forming a molten globular state followed by unfolding of secondary structures. Ligands that stabilize the enzyme in a pre-transition (PreTS) state compress the temperature range over which these transitions occur and sharpen the transitions to the molten globule and fully denatured states, while broadening the low-temperature transition. The experimental enthalpy changes provide a key parameter necessary to convert changes in melting temperature of combinatorial mutants into mutationally induced conformational free energy changes. The TrpRS urzyme, an excerpted model representing an early ancestral form, containing virtually the entire catalytic apparatus, remains largely intact at the highest simulated temperatures.
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Affiliation(s)
| | - Jhuma Das
- Cystic Fibrosis and Pulmonary Diseases Research and Treatment Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
| | - Nikolay V. Dokholyan
- Department of Pharmacology and Biochemistry and Molecular Biology, Penn State College of Medicine, Hershey, Pennsylvania 17033, USA
| | - Charles W. Carter
- Department of Biophysics and Biochemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA
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2
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Cross interactions between Apolipoprotein E and amyloid proteins in neurodegenerative diseases. Comput Struct Biotechnol J 2023; 21:1189-1204. [PMID: 36817952 PMCID: PMC9932299 DOI: 10.1016/j.csbj.2023.01.022] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Revised: 01/18/2023] [Accepted: 01/18/2023] [Indexed: 01/21/2023] Open
Abstract
Three common Apolipoprotein E isoforms, ApoE2, ApoE3, and ApoE4, are key regulators of lipid homeostasis, among other functions. Apolipoprotein E can interact with amyloid proteins. The isoforms differ by one or two residues at positions 112 and 158, and possess distinct structural conformations and functions, leading to isoform-specific roles in amyloid-based neurodegenerative diseases. Over 30 different amyloid proteins have been found to share similar characteristics of structure and toxicity, suggesting a common interactome. The molecular and genetic interactions of ApoE with amyloid proteins have been extensively studied in neurodegenerative diseases, but have not yet been well connected and clarified. Here we summarize essential features of the interactions between ApoE and different amyloid proteins, identify gaps in the understanding of the interactome and propose the general interaction mechanism between ApoE isoforms and amyloid proteins. Perhaps more importantly, this review outlines what we can learn from the interactome of ApoE and amyloid proteins; that is the need to see both ApoE and amyloid proteins as a basis to understand neurodegenerative diseases.
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3
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Apolipoprotein E in Cardiometabolic and Neurological Health and Diseases. Int J Mol Sci 2022; 23:ijms23179892. [PMID: 36077289 PMCID: PMC9456500 DOI: 10.3390/ijms23179892] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 08/25/2022] [Accepted: 08/28/2022] [Indexed: 11/17/2022] Open
Abstract
A preponderance of evidence obtained from genetically modified mice and human population studies reveals the association of apolipoprotein E (apoE) deficiency and polymorphisms with pathogenesis of numerous chronic diseases, including atherosclerosis, obesity/diabetes, and Alzheimer’s disease. The human APOE gene is polymorphic with three major alleles, ε2, ε3 and ε4, encoding apoE2, apoE3, and apoE4, respectively. The APOE gene is expressed in many cell types, including hepatocytes, adipocytes, immune cells of the myeloid lineage, vascular smooth muscle cells, and in the brain. ApoE is present in subclasses of plasma lipoproteins, and it mediates the clearance of atherogenic lipoproteins from plasma circulation via its interaction with LDL receptor family proteins and heparan sulfate proteoglycans. Extracellular apoE also interacts with cell surface receptors and confers signaling events for cell regulation, while apoE expressed endogenously in various cell types regulates cell functions via autocrine and paracrine mechanisms. This review article focuses on lipoprotein transport-dependent and -independent mechanisms by which apoE deficiency or polymorphisms contribute to cardiovascular disease, metabolic disease, and neurological disorders.
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4
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Rueter J, Rimbach G, Huebbe P. Functional diversity of apolipoprotein E: from subcellular localization to mitochondrial function. Cell Mol Life Sci 2022; 79:499. [PMID: 36018414 PMCID: PMC9418098 DOI: 10.1007/s00018-022-04516-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 07/27/2022] [Accepted: 08/07/2022] [Indexed: 11/26/2022]
Abstract
Human apolipoprotein E (APOE), originally known for its role in lipid metabolism, is polymorphic with three major allele forms, namely, APOEε2, APOEε3, and APOEε4, leading to three different human APOE isoforms. The ε4 allele is a genetic risk factor for Alzheimer's disease (AD); therefore, the vast majority of APOE research focuses on its role in AD pathology. However, there is increasing evidence for other functions of APOE through the involvement in other biological processes such as transcriptional regulation, mitochondrial metabolism, immune response, and responsiveness to dietary factors. Therefore, the aim of this review is to provide an overview of the potential novel functions of APOE and their characterization. The detection of APOE in various cell organelles points to previously unrecognized roles in mitochondria and others, although it is actually considered a secretory protein. Furthermore, numerous interactions of APOE with other proteins have been detected, providing indications for new metabolic pathways involving APOE. The present review summarizes the current evidence on APOE beyond its original role in lipid metabolism, to change the perspective and encourage novel approaches to future research on APOE and its isoform-dependent role in the cellular metabolism.
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Affiliation(s)
- Johanna Rueter
- Devision of Food Science, Institute of Human Nutrition and Food Science, University of Kiel, Hermann-Rodewald-Strasse 6, 24118, Kiel, Germany
| | - Gerald Rimbach
- Devision of Food Science, Institute of Human Nutrition and Food Science, University of Kiel, Hermann-Rodewald-Strasse 6, 24118, Kiel, Germany.
| | - Patricia Huebbe
- Devision of Food Science, Institute of Human Nutrition and Food Science, University of Kiel, Hermann-Rodewald-Strasse 6, 24118, Kiel, Germany
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5
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Chen Y, Strickland MR, Soranno A, Holtzman DM. Apolipoprotein E: Structural Insights and Links to Alzheimer Disease Pathogenesis. Neuron 2020; 109:205-221. [PMID: 33176118 DOI: 10.1016/j.neuron.2020.10.008] [Citation(s) in RCA: 136] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 10/05/2020] [Accepted: 10/06/2020] [Indexed: 01/02/2023]
Abstract
Apolipoprotein E (ApoE) is of great interest due to its role as a cholesterol/lipid transporter in the central nervous system (CNS) and as the most influential genetic risk factor for Alzheimer disease (AD). Work over the last four decades has given us important insights into the structure of ApoE and how this might impact the neuropathology and pathogenesis of AD. In this review, we highlight the history and progress in the structural and molecular understanding of ApoE and discuss how these studies on ApoE have illuminated the physiology of ApoE, receptor binding, and interaction with amyloid-β (Aβ). We also identify future areas of study needed to advance our understanding of how ApoE influences neurodegeneration.
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Affiliation(s)
- Yun Chen
- Department of Neurology, Washington University in St. Louis, St. Louis, MO, USA; Hope Center for Neurological Disorders, Washington University in St. Louis, St. Louis, MO, USA; Knight Alzheimer's Disease Research Center, Washington University in St. Louis, St. Louis, MO, USA; The Division of Biology and Biomedical Sciences, Washington University in St. Louis, St. Louis, MO, USA; Department of Pathology and Immunology, Washington University in St. Louis, St. Louis, MO, USA
| | - Michael R Strickland
- Department of Neurology, Washington University in St. Louis, St. Louis, MO, USA; Hope Center for Neurological Disorders, Washington University in St. Louis, St. Louis, MO, USA; Knight Alzheimer's Disease Research Center, Washington University in St. Louis, St. Louis, MO, USA; The Division of Biology and Biomedical Sciences, Washington University in St. Louis, St. Louis, MO, USA
| | - Andrea Soranno
- Department of Biochemistry and Molecular Biophysics, Washington University in St. Louis, St. Louis, MO, USA; Center for Science & Engineering of Living Systems, Washington University in St. Louis, St. Louis, MO, USA
| | - David M Holtzman
- Department of Neurology, Washington University in St. Louis, St. Louis, MO, USA; Center for Science & Engineering of Living Systems, Washington University in St. Louis, St. Louis, MO, USA; Knight Alzheimer's Disease Research Center, Washington University in St. Louis, St. Louis, MO, USA.
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6
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Apolipoprotein E4 exhibits intermediates with domain interaction. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2020; 1868:140535. [PMID: 32882410 DOI: 10.1016/j.bbapap.2020.140535] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 08/18/2020] [Accepted: 08/27/2020] [Indexed: 11/23/2022]
Abstract
ApoE4(C112R) is the strongest risk factor for Alzheimer's disease, while apoE3(C112) is considered normal. The C112R substitution is believed to alter the interactions between the N-terminal (NTD) and the C-terminal domain (CTD) leading to major functional differences. Here we investigate how the molecular property of the residue at position 112 affects domain interaction using an array of C112X substitutions with arginine, alanine, threonine, valine, leucine and isoleucine as 'X'. We attempt to determine the free energy of domain interaction (∆GINT) from stabilities of the NTD (∆GNTD) and CTD (∆GCTD) in the full-length apoE, and the stabilities of fragments of the NTD (∆GNTF) and CTD (∆GCTF), using the relationship, ∆GINT = ∆GNTD + ∆GCTD - ∆GNTF - ∆GCTF. We find that although ∆GNTD is strongly dependent on the C112X substitutions, ∆GNTD - ∆GNTF is small. Furthermore, ∆GCTD remains nearly the same as ∆GCTF. Therefore, ∆GINT is estimated to be small and similar for the apoE isoforms. However, stability of domain interaction monitored by urea dependent changes in interdomain Forster Resonance Energy Transfer (FRET) is found to be strongly dependent on C112X substitutions. ApoE4 exhibits the highest mid-point of denaturation of interdomain FRET. To resolve the apparently contradictory observations, we hypothesize that higher interdomain FRET in apoE4 in urea may involve 'intermediate' states. Enhanced fluorescence of bis-ANS and susceptibility to proteolytic cleavage support that apoE4, specifically, the NTD of apoE4 harbor 'intermediates' in both native and mildly denaturing conditions. The intermediates could hold key to the pathological functions of apoE4.
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7
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The Genetic Variability of APOE in Different Human Populations and Its Implications for Longevity. Genes (Basel) 2019; 10:genes10030222. [PMID: 30884759 PMCID: PMC6471373 DOI: 10.3390/genes10030222] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 03/01/2019] [Accepted: 03/12/2019] [Indexed: 12/11/2022] Open
Abstract
Human longevity is a complex phenotype resulting from the combinations of context-dependent gene-environment interactions that require analysis as a dynamic process in a cohesive ecological and evolutionary framework. Genome-wide association (GWAS) and whole-genome sequencing (WGS) studies on centenarians pointed toward the inclusion of the apolipoprotein E (APOE) polymorphisms ε2 and ε4, as implicated in the attainment of extreme longevity, which refers to their effect in age-related Alzheimer's disease (AD) and cardiovascular disease (CVD). In this case, the available literature on APOE and its involvement in longevity is described according to an anthropological and population genetics perspective. This aims to highlight the evolutionary history of this gene, how its participation in several biological pathways relates to human longevity, and which evolutionary dynamics may have shaped the distribution of APOE haplotypes across the globe. Its potential adaptive role will be described along with implications for the study of longevity in different human groups. This review also presents an updated overview of the worldwide distribution of APOE alleles based on modern day data from public databases and ancient DNA samples retrieved from literature in the attempt to understand the spatial and temporal frame in which present-day patterns of APOE variation evolved.
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8
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Ray A, Ahalawat N, Mondal J. Atomistic Insights into Structural Differences between E3 and E4 Isoforms of Apolipoprotein E. Biophys J 2018; 113:2682-2694. [PMID: 29262361 DOI: 10.1016/j.bpj.2017.10.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Revised: 10/04/2017] [Accepted: 10/05/2017] [Indexed: 12/23/2022] Open
Abstract
Among various isoforms of Apolipoprotein E (ApoE), the E4 isoform (ApoE4) is considered to be the strongest risk factor for Alzheimer's disease, whereas the E3 isoform (ApoE3) is neutral to the disease. Interestingly, the sequence of ApoE4 differs from its wild-type ApoE3 by a single amino acid C112R in the 299-amino-acid-long sequence. Hence, the puzzle remains: how a single-amino-acid difference between the ApoE3 and ApoE4 sequences can give rise to structural dissimilarities between the two isoforms, which can potentially lead to functional differences with significant pathological consequences. The major obstacle in addressing this question has been the lack of a 3D atomistic structure of ApoE4 to date. In this work, we resolve the issue by computationally modeling a plausible atomistic 3D structure of ApoE4. Our microsecond-long atomistic simulations elucidate key structural differences between monomeric ApoE3 and ApoE4, which renders ApoE4 thermodynamically less stable, less structured, and topologically less rigid compared to ApoE3. Consistent with an experimental report of the molten globule state of ApoE4, simulations identify multiple partially folded intermediates for ApoE4, which are implicated in the stronger aggregation propensity of ApoE4.
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Affiliation(s)
- Angana Ray
- Tata Institute of Fundamental Research, Hyderabad, Telangana, India
| | - Navjeet Ahalawat
- Tata Institute of Fundamental Research, Hyderabad, Telangana, India
| | - Jagannath Mondal
- Tata Institute of Fundamental Research, Hyderabad, Telangana, India.
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9
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Williams B, Convertino M, Das J, Dokholyan NV. Molecular Mechanisms of the R61T Mutation in Apolipoprotein E4: A Dynamic Rescue. Biophys J 2017; 113:2192-2198. [PMID: 28916386 PMCID: PMC5700245 DOI: 10.1016/j.bpj.2017.08.026] [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: 05/15/2017] [Revised: 07/02/2017] [Accepted: 08/17/2017] [Indexed: 10/18/2022] Open
Abstract
The apolipoprotein E4 (ApoE4) gene is the strongest genetic risk factor for Alzheimer's disease (AD). With respect to the other common isoforms of this protein (ApoE2 and ApoE3), ApoE4 is characterized by lower stability that underlies the formation of a stable interaction between the protein's N- and C-terminal domains. AD-related cellular dysfunctions have been linked to this ApoE4 misfolded state. In this regard, it has been reported that the mutation R61T is able to rescue the deleterious cellular effects of ApoE4 by preventing the formation of the misfolded intermediate state. However, a clear description of the structural features at the basis of the R61T-ApoE4 mutant's protective effect is still missing. Recently, using extensive molecular dynamics simulations, we have identified a structural model of an ApoE4 misfolded intermediate state. Building on our previous work, here we explore the dynamical changes induced by the R61T mutation in the ApoE4 native and misfolded states. Notably, we do not observe any local changes in the domains in the R61T-ApoE4 system, rather a general loss of correlated movements in the entire protein structure. More specifically, we detect increased dynamics in the hinge region, which is essential for ApoE4 domain-domain interaction. Consistent with previously reported data on altered phospholipid and receptor binding, we hypothesize that mutations destabilizing the ApoE4 intermediate state change hinge region dynamics, which propagates to distal functional regions of the protein and modifies ApoE4's functional properties. This unique behavior of the ApoE4 hinge region provides, to our knowledge, a novel understanding of ApoE4's role in AD.
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Affiliation(s)
- Benfeard Williams
- Biochemistry and Biophysics Department, University of North Carolina, Chapel Hill, North Carolina
| | - Marino Convertino
- Biochemistry and Biophysics Department, University of North Carolina, Chapel Hill, North Carolina
| | - Jhuma Das
- Biochemistry and Biophysics Department, University of North Carolina, Chapel Hill, North Carolina
| | - Nikolay V Dokholyan
- Biochemistry and Biophysics Department, University of North Carolina, Chapel Hill, North Carolina.
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10
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Huebbe P, Rimbach G. Evolution of human apolipoprotein E (APOE) isoforms: Gene structure, protein function and interaction with dietary factors. Ageing Res Rev 2017. [PMID: 28647612 DOI: 10.1016/j.arr.2017.06.002] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Apolipoprotein E (APOE) is a member of the vertebrate protein family of exchangeable apolipoproteins that is characterized by amphipathic α-helices encoded by multiple nucleotide tandem repeats. Its equivalent in flying insects - apolipophorin-III - shares structural and functional commonalities with APOE, suggesting the possibility of an evolutionary relationship between the proteins. In contrast to all other known species, human APOE is functionally polymorphic and possesses three major allelic variants (ε4, ε3 and ε2). The present review examines the current knowledge on APOE gene structure, phylogeny and APOE protein topology as well as its human isoforms. The ε4 allele is associated with an increased age-related disease risk but is also the ancestral form. Despite increased mortality in the elderly, ε4 has not become extinct and is the second-most common allele worldwide after ε3. APOE ε4, moreover, shows a non-random geographical distribution, and similarly, the ε2 allele is not homogenously distributed among ethnic populations. This likely suggests the existence of selective forces that are driving the evolution of human APOE isoforms, which may include differential interactions with dietary factors. To that effect, micronutrients such as vitamin D and carotenoids or dietary macronutrient composition are elucidated with respect to APOE evolution.
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Affiliation(s)
- Patricia Huebbe
- Institute of Human Nutrition and Food Science, University of Kiel, H. Rodewald Str. 6, 24118 Kiel, Germany.
| | - Gerald Rimbach
- Institute of Human Nutrition and Food Science, University of Kiel, H. Rodewald Str. 6, 24118 Kiel, Germany.
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11
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Musiani F, Giorgetti A. Protein Aggregation and Molecular Crowding: Perspectives From Multiscale Simulations. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2016; 329:49-77. [PMID: 28109331 DOI: 10.1016/bs.ircmb.2016.08.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Cells are extremely crowded environments, thus the use of diluted salted aqueous solutions containing a single protein is too simplistic to mimic the real situation. Macromolecular crowding might affect protein structure, folding, shape, conformational stability, binding of small molecules, enzymatic activity, interactions with cognate biomolecules, and pathological aggregation. The latter phenomenon typically leads to the formation of amyloid fibrils that are linked to several lethal neurodegenerative diseases, but that can also play a functional role in certain organisms. The majority of molecular simulations performed before the last few years were conducted in diluted solutions and were restricted both in the timescales and in the system dimensions by the available computational resources. In recent years, several computational solutions were developed to get close to physiological conditions. In this review we summarize the main computational techniques used to tackle the issue of protein aggregation both in a diluted and in a crowded environment.
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Affiliation(s)
- F Musiani
- Laboratory of Bioinorganic Chemistry, University of Bologna, Bologna, Italy.
| | - A Giorgetti
- Applied Bioinformatics Group, University of Verona, Verona, Italy.
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12
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The ability of apolipoprotein E fragments to promote intraneuronal accumulation of amyloid beta peptide 42 is both isoform and size-specific. Sci Rep 2016; 6:30654. [PMID: 27476701 PMCID: PMC4967930 DOI: 10.1038/srep30654] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Accepted: 07/07/2016] [Indexed: 11/15/2022] Open
Abstract
The apolipoprotein (apo) E4 isoform is the strongest risk factor for late-onset Alzheimer’s disease (AD). ApoE4 is more susceptible to proteolysis than apoE2 and apoE3 isoforms and carboxyl-terminal truncated apoE4 forms have been found in AD patients’ brain. We have previously shown that a specific apoE4 fragment, apoE4-165, promotes amyloid-peptide beta 42 (Aβ42) accumulation in human neuroblastoma SK-N-SH cells and increased intracellular reactive oxygen species formation, two events considered to occur early in AD pathogenesis. Here, we show that these effects are allele-dependent and absolutely require the apoE4 background. Furthermore, the exact length of the fragment is critical since longer or shorter length carboxyl-terminal truncated apoE4 forms do not elicit the same effects. Structural and thermodynamic analyses showed that apoE4-165 has a compact structure, in contrast to other carboxyl-terminal truncated apoE4 forms that are instead destabilized. Compared however to other allelic backgrounds, apoE4-165 is structurally distinct and less thermodynamically stable suggesting that the combination of a well-folded structure with structural plasticity is a unique characteristic of this fragment. Overall, our findings suggest that the ability of apoE fragments to promote Aβ42 intraneuronal accumulation is specific for both the apoE4 isoform and the particular structural and thermodynamic properties of the fragment.
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13
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Dose J, Huebbe P, Nebel A, Rimbach G. APOE genotype and stress response - a mini review. Lipids Health Dis 2016; 15:121. [PMID: 27457486 PMCID: PMC4960866 DOI: 10.1186/s12944-016-0288-2] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Accepted: 07/12/2016] [Indexed: 12/31/2022] Open
Abstract
The APOE gene is one of currently only two genes that have consistently been associated with longevity. Apolipoprotein E (APOE) is a plasma protein which plays an important role in lipid and lipoprotein metabolism. In humans, there are three major APOE isoforms, designated APOE2, APOE3, and APOE4. Of these three isoforms, APOE3 is most common while APOE4 was shown to be associated with age-related diseases, including cardiovascular and Alzheimer’s disease, and therefore an increased mortality risk with advanced age. Evidence accumulates, showing that oxidative stress and, correspondingly, mitochondrial function is affected in an APOE isoform-dependent manner. Accordingly, several stress response pathways implicated in the aging process, including the endoplasmic reticulum stress response and immune function, appear to be influenced by the APOE genotype. The investigation and development of treatment strategies targeting APOE4 have not resolved any therapeutic yet that could be entirely recommended. This mini-review provides an overview on the state of research concerning the impact of the APOE genotype on stress response-related processes, emphasizing the strong interconnection between mitochondrial function, endoplasmic reticulum stress and the immune response. Furthermore, this review addresses potential treatment strategies and associated pitfalls as well as lifestyle interventions that could benefit people with an at risk APOE4 genotype.
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Affiliation(s)
- Janina Dose
- Institute of Human Nutrition and Food Science, Kiel University, Hermann-Rodewald-Str. 6, D-24118, Kiel, Germany. .,Institute of Clinical Molecular Biology, Kiel University, Schittenhelmstr. 12, D-24105, Kiel, Germany.
| | - Patricia Huebbe
- Institute of Human Nutrition and Food Science, Kiel University, Hermann-Rodewald-Str. 6, D-24118, Kiel, Germany
| | - Almut Nebel
- Institute of Clinical Molecular Biology, Kiel University, Schittenhelmstr. 12, D-24105, Kiel, Germany
| | - Gerald Rimbach
- Institute of Human Nutrition and Food Science, Kiel University, Hermann-Rodewald-Str. 6, D-24118, Kiel, Germany
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14
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Convertino M, Das J, Dokholyan NV. Pharmacological Chaperones: Design and Development of New Therapeutic Strategies for the Treatment of Conformational Diseases. ACS Chem Biol 2016; 11:1471-89. [PMID: 27097127 DOI: 10.1021/acschembio.6b00195] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Errors in protein folding may result in premature clearance of structurally aberrant proteins, or in the accumulation of toxic misfolded species or protein aggregates. These pathological events lead to a large range of conditions known as conformational diseases. Several research groups have presented possible therapeutic solutions for their treatment by developing novel compounds, known as pharmacological chaperones. These cell-permeable molecules selectively provide a molecular scaffold around which misfolded proteins can recover their native folding and, thus, their biological activities. Here, we review therapeutic strategies, clinical potentials, and cost-benefit impacts of several classes of pharmacological chaperones for the treatment of a series of conformational diseases.
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Affiliation(s)
- Marino Convertino
- Department of Biochemistry
and Biophysics, University of North Carolina, 120 Mason Farm Road, Chapel Hill, North Carolina 27599, United States
| | - Jhuma Das
- Department of Biochemistry
and Biophysics, University of North Carolina, 120 Mason Farm Road, Chapel Hill, North Carolina 27599, United States
| | - Nikolay V. Dokholyan
- Department of Biochemistry
and Biophysics, University of North Carolina, 120 Mason Farm Road, Chapel Hill, North Carolina 27599, United States
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15
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Chandrasekaran SN, Das J, Dokholyan NV, Carter CW. A modified PATH algorithm rapidly generates transition states comparable to those found by other well established algorithms. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2016; 3:012101. [PMID: 26958584 PMCID: PMC4769271 DOI: 10.1063/1.4941599] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 01/22/2016] [Indexed: 06/05/2023]
Abstract
PATH rapidly computes a path and a transition state between crystal structures by minimizing the Onsager-Machlup action. It requires input parameters whose range of values can generate different transition-state structures that cannot be uniquely compared with those generated by other methods. We outline modifications to estimate these input parameters to circumvent these difficulties and validate the PATH transition states by showing consistency between transition-states derived by different algorithms for unrelated protein systems. Although functional protein conformational change trajectories are to a degree stochastic, they nonetheless pass through a well-defined transition state whose detailed structural properties can rapidly be identified using PATH.
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Affiliation(s)
- Srinivas Niranj Chandrasekaran
- Department of Biochemistry and Biophysics, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599-7260, USA
| | - Jhuma Das
- Department of Biochemistry and Biophysics, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599-7260, USA
| | - Nikolay V Dokholyan
- Department of Biochemistry and Biophysics, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599-7260, USA
| | - Charles W Carter
- Department of Biochemistry and Biophysics, The University of North Carolina at Chapel Hill , Chapel Hill, North Carolina 27599-7260, USA
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Proctor EA, Dokholyan NV. Applications of Discrete Molecular Dynamics in biology and medicine. Curr Opin Struct Biol 2015; 37:9-13. [PMID: 26638022 DOI: 10.1016/j.sbi.2015.11.001] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 10/28/2015] [Accepted: 11/05/2015] [Indexed: 11/27/2022]
Abstract
Discrete Molecular Dynamics (DMD) is a physics-based simulation method using discrete energetic potentials rather than traditional continuous potentials, allowing microsecond time scale simulations of biomolecular systems to be performed on personal computers rather than supercomputers or specialized hardware. With the ongoing explosion in processing power even in personal computers, applications of DMD have similarly multiplied. In the past two years, researchers have used DMD to model structures of disease-implicated protein folding intermediates, study assembly of protein complexes, predict protein-protein binding conformations, engineer rescue mutations in disease-causative protein mutants, design a protein conformational switch to control cell signaling, and describe the behavior of polymeric dispersants for environmental cleanup of oil spills, among other innovative applications.
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Affiliation(s)
- Elizabeth A Proctor
- Department of Biological Engineering, Massachusetts Institute of Technology, United States.
| | - Nikolay V Dokholyan
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, United States.
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