1
|
Li F, Li W. Readers of RNA Modification in Cancer and Their Anticancer Inhibitors. Biomolecules 2024; 14:881. [PMID: 39062595 PMCID: PMC11275166 DOI: 10.3390/biom14070881] [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: 06/18/2024] [Revised: 07/19/2024] [Accepted: 07/21/2024] [Indexed: 07/28/2024] Open
Abstract
Cancer treatment has always been a challenge for humanity. The inadequacies of current technologies underscore the limitations of our efforts against this disease. Nevertheless, the advent of targeted therapy has introduced a promising avenue, furnishing us with more efficacious tools. Consequently, researchers have turned their attention toward epigenetics, offering a novel perspective in this realm. The investigation of epigenetics has brought RNA readers to the forefront, as they play pivotal roles in recognizing and regulating RNA functions. Recently, the development of inhibitors targeting these RNA readers has emerged as a focal point in research and holds promise for further strides in targeted therapy. In this review, we comprehensively summarize various types of inhibitors targeting RNA readers, including non-coding RNA (ncRNA) inhibitors, small-molecule inhibitors, and other potential inhibitors. We systematically elucidate their mechanisms in suppressing cancer progression by inhibiting readers, aiming to present inhibitors of readers at the current stage and provide more insights into the development of anticancer drugs.
Collapse
Affiliation(s)
| | - Wenjin Li
- Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China;
| |
Collapse
|
2
|
Yedla P, Bhamidipati P, Syed R, Amanchy R. Working title: Molecular involvement of p53-MDM2 interactome in gastrointestinal cancers. Cell Biochem Funct 2024; 42:e4075. [PMID: 38924101 DOI: 10.1002/cbf.4075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 05/30/2024] [Accepted: 06/04/2024] [Indexed: 06/28/2024]
Abstract
The interaction between murine double minute 2 (MDM2) and p53, marked by transcriptional induction and feedback inhibition, orchestrates a functional loop dictating cellular fate. The functional loop comprising p53-MDM2 axis is made up of an interactome consisting of approximately 81 proteins, which are spatio-temporally regulated and involved in DNA repair mechanisms. Biochemical and genetic alterations of the interactome result in dysregulation of the p53-mdm2 axis that leads to gastrointestinal (GI) cancers. A large subset of interactome is well known and it consists of proteins that either stabilize p53 or MDM2 and proteins that target the p53-MDM2 complex for ubiquitin-mediated destruction. Upstream signaling events brought about by growth factors and chemical messengers invoke a wide variety of posttranslational modifications in p53-MDM2 axis. Biochemical changes in the transactivation domain of p53 impact the energy landscape, induce conformational switching, alter interaction potential and could change solubility of p53 to redefine its co-localization, translocation and activity. A diverse set of chemical compounds mimic physiological effectors and simulate biochemical modifications of the p53-MDM2 interactome. p53-MDM2 interactome plays a crucial role in DNA damage and repair process. Genetic aberrations in the interactome, have resulted in cancers of GI tract (pancreas, liver, colorectal, gastric, biliary, and esophageal). We present in this article a review of the overall changes in the p53-MDM2 interactors and the effectors that form an epicenter for the development of next-generation molecules for understanding and targeting GI cancers.
Collapse
Affiliation(s)
- Poornachandra Yedla
- Division of Applied Biology, CSIR-IICT (Indian Institute of Chemical Technology), Ministry of Science and Technology (GOI), Hyderabad, Telangana, India
- Department of Pharmacogenomics, Institute of Translational Research, Asian Healthcare Foundation, Hyderabad, Telangana, India
| | - Pranav Bhamidipati
- Division of Applied Biology, CSIR-IICT (Indian Institute of Chemical Technology), Ministry of Science and Technology (GOI), Hyderabad, Telangana, India
- Department of Life Sciences, Imperial College London, London, UK
| | - Riyaz Syed
- Division of Applied Biology, CSIR-IICT (Indian Institute of Chemical Technology), Ministry of Science and Technology (GOI), Hyderabad, Telangana, India
| | - Ramars Amanchy
- Division of Applied Biology, CSIR-IICT (Indian Institute of Chemical Technology), Ministry of Science and Technology (GOI), Hyderabad, Telangana, India
| |
Collapse
|
3
|
Patil H, Yi H, Cho KI, Ferreira PA. Proteostatic Remodeling of Small Heat Shock Chaperones─Crystallins by Ran-Binding Protein 2─and the Peptidyl-Prolyl cis-trans Isomerase and Chaperone Activities of Its Cyclophilin Domain. ACS Chem Neurosci 2024; 15:1967-1989. [PMID: 38657106 DOI: 10.1021/acschemneuro.3c00792] [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: 04/26/2024] Open
Abstract
Disturbances in protein phase transitions promote protein aggregation─a neurodegeneration hallmark. The modular Ran-binding protein 2 (Ranbp2) is a cytosolic molecular hub for rate-limiting steps of phase transitions of Ran-GTP-bound protein ensembles exiting nuclear pores. Chaperones also regulate phase transitions and proteostasis by suppressing protein aggregation. Ranbp2 haploinsufficiency promotes the age-dependent neuroprotection of the chorioretina against phototoxicity by proteostatic regulations of neuroprotective substrates of Ranbp2 and by suppressing the buildup of polyubiquitylated substrates. Losses of peptidyl-prolyl cis-trans isomerase (PPIase) and chaperone activities of the cyclophilin domain (CY) of Ranbp2 recapitulate molecular effects of Ranbp2 haploinsufficiency. These CY impairments also stimulate deubiquitylation activities and phase transitions of 19S cap subunits of the 26S proteasome that associates with Ranbp2. However, links between CY moonlighting activity, substrate ubiquitylation, and proteostasis remain incomplete. Here, we reveal the Ranbp2 regulation of small heat shock chaperones─crystallins in the chorioretina by proteomics of mice with total or selective modular deficits of Ranbp2. Specifically, loss of CY PPIase of Ranbp2 upregulates αA-Crystallin, which is repressed in adult nonlenticular tissues. Conversely, impairment of CY's chaperone activity opposite to the PPIase pocket downregulates a subset of αA-Crystallin's substrates, γ-crystallins. These CY-dependent effects cause age-dependent and chorioretinal-selective declines of ubiquitylated substrates without affecting the chorioretinal morphology. A model emerges whereby inhibition of Ranbp2's CY PPIase remodels crystallins' expressions, subdues molecular aging, and preordains the chorioretina to neuroprotection by augmenting the chaperone capacity and the degradation of polyubiquitylated substrates against proteostatic impairments. Further, the druggable Ranbp2 CY holds pan-therapeutic potential against proteotoxicity and neurodegeneration.
Collapse
Affiliation(s)
- Hemangi Patil
- Department of Ophthalmology Duke University Medical Center, Durham, North Carolina 27710, United States
| | - Haiqing Yi
- Department of Ophthalmology Duke University Medical Center, Durham, North Carolina 27710, United States
| | - Kyoung-In Cho
- Department of Ophthalmology Duke University Medical Center, Durham, North Carolina 27710, United States
| | - Paulo A Ferreira
- Department of Ophthalmology Duke University Medical Center, Durham, North Carolina 27710, United States
- Department of Pathology Duke University Medical Center, Durham, North Carolina 27710, United States
| |
Collapse
|
4
|
Patil H, Cho KI, Ferreira PA. Proteostatic remodeling of small heat shock chaperones - crystallins by Ran-binding protein 2 and the peptidyl-prolyl cis-trans isomerase and chaperone activities of its cyclophilin domain. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.26.577462. [PMID: 38352504 PMCID: PMC10862737 DOI: 10.1101/2024.01.26.577462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2024]
Abstract
Disturbances in phase transitions and intracellular partitions of nucleocytoplasmic shuttling substrates promote protein aggregation - a hallmark of neurodegenerative diseases. The modular Ran-binding protein 2 (Ranbp2) is a cytosolic molecular hub for rate-limiting steps of disassembly and phase transitions of Ran-GTP-bound protein ensembles exiting nuclear pores. Chaperones also play central roles in phase transitions and proteostasis by suppressing protein aggregation. Ranbp2 haploinsufficiency promotes the age-dependent neuroprotection of the chorioretina against photo-oxidative stress by proteostatic regulations of Ranbp2 substrates and by countering the build-up of poly-ubiquitylated substrates. Further, the peptidyl-prolyl cis-trans isomerase (PPIase) and chaperone activities of the cyclophilin domain (CY) of Ranbp2 modulate the proteostasis of selective neuroprotective substrates, such as hnRNPA2B1, STAT3, HDAC4 or L/M-opsin, while promoting a decline of ubiquitylated substrates. However, links between CY PPIase activity on client substrates and its effect(s) on ubiquitylated substrates are unclear. Here, proteomics of genetically modified mice with deficits of Ranbp2 uncovered the regulation of the small heat shock chaperones - crystallins by Ranbp2 in the chorioretina. Loss of CY PPIase of Ranbp2 up-regulates αA-crystallin proteostasis, which is repressed in non-lenticular tissues. Conversely, the αA-crystallin's substrates, γ-crystallins, are down-regulated by impairment of CY's C-terminal chaperone activity. These CY-dependent effects cause the age-dependent decline of ubiquitylated substrates without overt chorioretinal morphological changes. A model emerges whereby the Ranbp2 CY-dependent remodeling of crystallins' proteostasis subdues molecular aging and preordains chorioretinal neuroprotection by augmenting the chaperone buffering capacity and the decline of ubiquitylated substrates against proteostatic impairments. Further, CY's moonlighting activity holds pan -therapeutic potential against neurodegeneration.
Collapse
|
5
|
Ferreira PA. Nucleocytoplasmic transport at the crossroads of proteostasis, neurodegeneration and neuroprotection. FEBS Lett 2023; 597:2567-2589. [PMID: 37597509 DOI: 10.1002/1873-3468.14722] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Revised: 08/04/2023] [Accepted: 08/05/2023] [Indexed: 08/21/2023]
Abstract
Nucleocytoplasmic transport comprises the multistep assembly, transport, and disassembly of protein and RNA cargoes entering and exiting nuclear pores. Accruing evidence supports that impairments to nucleocytoplasmic transport are a hallmark of neurodegenerative diseases. These impairments cause dysregulations in nucleocytoplasmic partitioning and proteostasis of nuclear transport receptors and client substrates that promote intracellular deposits - another hallmark of neurodegeneration. Disturbances in liquid-liquid phase separation (LLPS) between dense and dilute phases of biomolecules implicated in nucleocytoplasmic transport promote micrometer-scale coacervates, leading to proteinaceous aggregates. This Review provides historical and emerging principles of LLPS at the interface of nucleocytoplasmic transport, proteostasis, aging and noxious insults, whose dysregulations promote intracellular aggregates. E3 SUMO-protein ligase Ranbp2 constitutes the cytoplasmic filaments of nuclear pores, where it acts as a molecular hub for rate-limiting steps of nucleocytoplasmic transport. A vignette is provided on the roles of Ranbp2 in nucleocytoplasmic transport and at the intersection of proteostasis in the survival of photoreceptor and motor neurons under homeostatic and pathophysiological environments. Current unmet clinical needs are highlighted, including therapeutics aiming to manipulate aggregation-dissolution models of purported neurotoxicity in neurodegeneration.
Collapse
Affiliation(s)
- Paulo A Ferreira
- Department of Ophthalmology, Department of Pathology, Duke University Medical Center, NC, Durham, USA
| |
Collapse
|
6
|
Abstract
Dominant missense mutations in RanBP2/Nup358 cause Acute Necrotizing Encephalopathy (ANE), a pediatric disease where seemingly healthy individuals develop a cytokine storm that is restricted to the central nervous system in response to viral infection. Untreated, this condition leads to seizures, coma, long-term neurological damage and a high rate of mortality. The exact mechanism by which RanBP2 mutations contribute to the development of ANE remains elusive. In November 2021, a number of clinicians and basic scientists presented their work on this disease and on the interactions between RanBP2/Nup358, viral infections, the innate immune response and other cellular processes.
Collapse
Affiliation(s)
| | - Jomon Joseph
- National Centre for Cell Science, S.P. Pune University Campus, Pune, India
| | - Ming Lim
- Children's Neurosciences, Evelina London Children's Hospital, and the Department of Women and Children's Health, King's College London, London, UK
| | - Kiran T Thakur
- Department of Neurology, Vagelos College of Physicians and Surgeons, Columbia University Irving Medical Center, and the New York Presbyterian Hospital, New York
| |
Collapse
|
7
|
Cho KI, Yoon D, Yu M, Peachey NS, Ferreira PA. Microglial activation in an amyotrophic lateral sclerosis-like model caused by Ranbp2 loss and nucleocytoplasmic transport impairment in retinal ganglion neurons. Cell Mol Life Sci 2019; 76:3407-3432. [PMID: 30944974 PMCID: PMC6698218 DOI: 10.1007/s00018-019-03078-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 02/21/2019] [Accepted: 03/18/2019] [Indexed: 12/12/2022]
Abstract
Nucleocytoplasmic transport is dysregulated in sporadic and familial amyotrophic lateral sclerosis (ALS) and retinal ganglion neurons (RGNs) are purportedly involved in ALS. The Ran-binding protein 2 (Ranbp2) controls rate-limiting steps of nucleocytoplasmic transport. Mice with Ranbp2 loss in Thy1+-motoneurons develop cardinal ALS-like motor traits, but the impairments in RGNs and the degree of dysfunctional consonance between RGNs and motoneurons caused by Ranbp2 loss are unknown. This will help to understand the role of nucleocytoplasmic transport in the differential vulnerability of neuronal cell types to ALS and to uncover non-motor endophenotypes with pathognomonic signs of ALS. Here, we ascertain Ranbp2's function and endophenotypes in RGNs of an ALS-like mouse model lacking Ranbp2 in motoneurons and RGNs. Thy1+-RGNs lacking Ranbp2 shared with motoneurons the dysregulation of nucleocytoplasmic transport. RGN abnormalities were comprised morphologically by soma hypertrophy and optic nerve axonopathy and physiologically by a delay of the visual pathway's evoked potentials. Whole-transcriptome analysis showed restricted transcriptional changes in optic nerves that were distinct from those found in sciatic nerves. Specifically, the level and nucleocytoplasmic partition of the anti-apoptotic and novel substrate of Ranbp2, Pttg1/securin, were dysregulated. Further, acetyl-CoA carboxylase 1, which modulates de novo synthesis of fatty acids and T-cell immunity, showed the highest up-regulation (35-fold). This effect was reflected by the activation of ramified CD11b+ and CD45+-microglia, increase of F4\80+-microglia and a shift from pseudopodial/lamellipodial to amoeboidal F4\80+-microglia intermingled between RGNs of naive mice. Further, there was the intracellular sequestration in RGNs of metalloproteinase-28, which regulates macrophage recruitment and polarization in inflammation. Hence, Ranbp2 genetic insults in RGNs and motoneurons trigger distinct paracrine signaling likely by the dysregulation of nucleocytoplasmic transport of neuronal-type selective substrates. Immune-modulators underpinning RGN-to-microglial signaling are regulated by Ranbp2, and this neuronal-glial system manifests endophenotypes that are likely useful in the prognosis and diagnosis of motoneuron diseases, such as ALS.
Collapse
Affiliation(s)
- Kyoung-In Cho
- Department of Ophthalmology, Duke University Medical Center, DUEC 3802, 2351 Erwin Road, Durham, NC, 27710, USA
| | - Dosuk Yoon
- Department of Ophthalmology, Duke University Medical Center, DUEC 3802, 2351 Erwin Road, Durham, NC, 27710, USA
| | - Minzhong Yu
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic Foundation, Cleveland, OH, 44195, USA
- Department of Ophthalmology, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, 44195, USA
| | - Neal S Peachey
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic Foundation, Cleveland, OH, 44195, USA
- Research Service, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, OH, 44106, USA
- Department of Ophthalmology, Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, 44195, USA
| | - Paulo A Ferreira
- Department of Ophthalmology, Duke University Medical Center, DUEC 3802, 2351 Erwin Road, Durham, NC, 27710, USA.
| |
Collapse
|
8
|
Ferreira PA. The coming-of-age of nucleocytoplasmic transport in motor neuron disease and neurodegeneration. Cell Mol Life Sci 2019; 76:2247-2273. [PMID: 30742233 PMCID: PMC6531325 DOI: 10.1007/s00018-019-03029-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 01/28/2019] [Indexed: 12/11/2022]
Abstract
The nuclear pore is the gatekeeper of nucleocytoplasmic transport and signaling through which a vast flux of information is continuously exchanged between the nuclear and cytoplasmic compartments to maintain cellular homeostasis. A unifying and organizing principle has recently emerged that cements the notion that several forms of amyotrophic lateral sclerosis (ALS), and growing number of other neurodegenerative diseases, co-opt the dysregulation of nucleocytoplasmic transport and that this impairment is a pathogenic driver of neurodegeneration. The understanding of shared pathomechanisms that underpin neurodegenerative diseases with impairments in nucleocytoplasmic transport and how these interface with current concepts of nucleocytoplasmic transport is bound to illuminate this fundamental biological process in a yet more physiological context. Here, I summarize unresolved questions and evidence and extend basic and critical concepts and challenges of nucleocytoplasmic transport and its role in the pathogenesis of neurodegenerative diseases, such as ALS. These principles will help to appreciate the roles of nucleocytoplasmic transport in the pathogenesis of ALS and other neurodegenerative diseases, and generate a framework for new ideas of the susceptibility of motoneurons, and possibly other neurons, to degeneration by dysregulation of nucleocytoplasmic transport.
Collapse
Affiliation(s)
- Paulo A Ferreira
- Duke University Medical Center, DUEC 3802, 2351 Erwin Road, Durham, NC, 27710, USA.
| |
Collapse
|
9
|
De Simone A, Georgiou C, Ioannidis H, Gupta AA, Juárez-Jiménez J, Doughty-Shenton D, Blackburn EA, Wear MA, Richards JP, Barlow PN, Carragher N, Walkinshaw MD, Hulme AN, Michel J. A computationally designed binding mode flip leads to a novel class of potent tri-vector cyclophilin inhibitors. Chem Sci 2019; 10:542-547. [PMID: 30746096 PMCID: PMC6335623 DOI: 10.1039/c8sc03831g] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 10/14/2018] [Indexed: 12/27/2022] Open
Abstract
Cyclophilins (Cyps) are a major family of drug targets that are challenging to prosecute with small molecules because the shallow nature and high degree of conservation of the active site across human isoforms offers limited opportunities for potent and selective inhibition. Herein a computational approach based on molecular dynamics simulations and free energy calculations was combined with biophysical assays and X-ray crystallography to explore a flip in the binding mode of a reported urea-based Cyp inhibitor. This approach enabled access to a distal pocket that is poorly conserved among key Cyp isoforms, and led to the discovery of a new family of sub-micromolar cell-active inhibitors that offer unprecedented opportunities for the development of next-generation drug therapies based on Cyp inhibition. The computational approach is applicable to a broad range of organic functional groups and could prove widely enabling in molecular design.
Collapse
Affiliation(s)
- Alessio De Simone
- University of Edinburgh , Joseph Black Building, King's Buildings, David Brewster Road , Edinburgh , Scotland EH9 3FJ , UK .
| | - Charis Georgiou
- University of Edinburgh , Joseph Black Building, King's Buildings, David Brewster Road , Edinburgh , Scotland EH9 3FJ , UK .
| | - Harris Ioannidis
- University of Edinburgh , Joseph Black Building, King's Buildings, David Brewster Road , Edinburgh , Scotland EH9 3FJ , UK .
| | - Arun A Gupta
- University of Edinburgh , Joseph Black Building, King's Buildings, David Brewster Road , Edinburgh , Scotland EH9 3FJ , UK .
| | - Jordi Juárez-Jiménez
- University of Edinburgh , Joseph Black Building, King's Buildings, David Brewster Road , Edinburgh , Scotland EH9 3FJ , UK .
| | - Dahlia Doughty-Shenton
- Edinburgh Phenotypic Assay Centre , University of Edinburgh , Queen's Medical Research Institute , Little France Cres , Edinburgh , Scotland EH16 4TJ , UK
| | - Elizabeth A Blackburn
- The Edinburgh Protein Production Facility (EPPF) , University of Edinburgh , Level 3 Michael Swann Building, King's Buildings, Max Born Crescent , Edinburgh , Scotland EH9 3BF , UK
| | - Martin A Wear
- The Edinburgh Protein Production Facility (EPPF) , University of Edinburgh , Level 3 Michael Swann Building, King's Buildings, Max Born Crescent , Edinburgh , Scotland EH9 3BF , UK
| | - Jonathan P Richards
- University of Edinburgh , Joseph Black Building, King's Buildings, David Brewster Road , Edinburgh , Scotland EH9 3FJ , UK .
| | - Paul N Barlow
- University of Edinburgh , Joseph Black Building, King's Buildings, David Brewster Road , Edinburgh , Scotland EH9 3FJ , UK .
| | - Neil Carragher
- Cancer Research UK Edinburgh Centre , University of Edinburgh , MRC Institute of Genetics and Molecular Medicine , Crewe Road South , Edinburgh , Scotland EH4 2XR , UK
| | - Malcolm D Walkinshaw
- University of Edinburgh , Michael Swann Building, Max Born Crescent , Edinburgh , Scotland EH9 3BF , UK
| | - Alison N Hulme
- University of Edinburgh , Joseph Black Building, King's Buildings, David Brewster Road , Edinburgh , Scotland EH9 3FJ , UK .
| | - Julien Michel
- University of Edinburgh , Joseph Black Building, King's Buildings, David Brewster Road , Edinburgh , Scotland EH9 3FJ , UK .
| |
Collapse
|
10
|
Wei X, Zhu D, Feng C, Chen G, Mao X, Wang Q, Wang J, Liu C. Inhibition of peptidyl-prolyl cis-trans isomerase B mediates cyclosporin A-induced apoptosis of islet β cells. Exp Ther Med 2018; 16:3959-3964. [PMID: 30344674 PMCID: PMC6176207 DOI: 10.3892/etm.2018.6706] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Accepted: 08/29/2018] [Indexed: 12/21/2022] Open
Abstract
Cyclosporin A (CsA) is widely used as an immunosuppressor in the context of organ transplantation or autoimmune disorders. Recent studies have revealed the detrimental effects of CsA on insulin resistance and pancreatic β cell failure; however, the molecular mechanisms are unknown. The present study sought to confirm the associations between CsA and β cell failure, and to investigate the roles of proinsulin folding and endoplasmic reticulum (ER) stress in CsA-induced β cell failure. The viability of MIN6 cells treated with CsA was evaluated with MTT assay. Expression levels of insulin, peptidyl-prolyl cis-trans isomerase B (PPIB), cleaved caspase-3, phospho-protein kinase R (PKR)-like endoplasmic reticulum kinase (p-PERK), PKR-like endoplasmic reticulum kinase (PERK), binding immunoglobulin protein (BIP), and C/EBP homologous protein (CHOP) were detected via reducing western blot assay. Non-reducing western blot analysis was performed to examine the expression of misfolded proinsulin peptides. The proliferation of MIN6 cells was not inhibited by CsA at concentrations <1 µmol/l. CsA treatment resulted in the decreased expression of insulin and PPIB; however, it also increased the phosphorylation of PERK, and upregulated the expression of PERK, BIP, CHOP and cleaved caspase-3. The results indicated that CsA could induce pancreatic β cell dysfunction and the potential mechanism underlying this phenomenon may be PPIB-associated proinsulin misfolding, which in turn induces ER stress in β cells.
Collapse
Affiliation(s)
- Xiao Wei
- Department of Endocrinology, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210028, P.R. China
| | - Dan Zhu
- Department of Endocrinology, Jiangdu People's Hospital of Yangzhou, Yangzhou, Jiangsu 225200, P.R. China
| | - Chenchen Feng
- Central Laboratory, Jiangsu Province Blood Center, Nanjing, Jiangsu 210042, P.R. China
| | - Guofang Chen
- Department of Endocrinology, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210028, P.R. China
| | - Xiaodong Mao
- Department of Endocrinology, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210028, P.R. China
| | - Qifeng Wang
- Department of Endocrinology, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210028, P.R. China
| | - Jie Wang
- Department of Endocrinology, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210028, P.R. China
| | - Chao Liu
- Department of Endocrinology, Affiliated Hospital of Integrated Traditional Chinese and Western Medicine, Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210028, P.R. China
| |
Collapse
|
11
|
Cho KI, Yoon D, Qiu S, Danziger Z, Grill WM, Wetsel WC, Ferreira PA. Loss of Ranbp2 in motoneurons causes disruption of nucleocytoplasmic and chemokine signaling, proteostasis of hnRNPH3 and Mmp28, and development of amyotrophic lateral sclerosis-like syndromes. Dis Model Mech 2017; 10:559-579. [PMID: 28100513 PMCID: PMC5451164 DOI: 10.1242/dmm.027730] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Accepted: 12/12/2016] [Indexed: 12/12/2022] Open
Abstract
The pathogenic drivers of sporadic and familial motor neuron disease (MND), such amyotrophic lateral sclerosis (ALS), are unknown. MND impairs the Ran GTPase cycle, which controls nucleocytoplasmic transport, ribostasis and proteostasis; however, cause-effect mechanisms of Ran GTPase modulators in motoneuron pathobiology have remained elusive. The cytosolic and peripheral nucleoporin Ranbp2 is a crucial regulator of the Ran GTPase cycle and of the proteostasis of neurological disease-prone substrates, but the roles of Ranbp2 in motoneuron biology and disease remain unknown. This study shows that conditional ablation of Ranbp2 in mouse Thy1 motoneurons causes ALS syndromes with hypoactivity followed by hindlimb paralysis, respiratory distress and, ultimately, death. These phenotypes are accompanied by: a decline in the nerve conduction velocity, free fatty acids and phophatidylcholine of the sciatic nerve; a reduction in the g-ratios of sciatic and phrenic nerves; and hypertrophy of motoneurons. Furthermore, Ranbp2 loss disrupts the nucleocytoplasmic partitioning of the import and export nuclear receptors importin β and exportin 1, respectively, Ran GTPase and histone deacetylase 4. Whole-transcriptome, proteomic and cellular analyses uncovered that the chemokine receptor Cxcr4, its antagonizing ligands Cxcl12 and Cxcl14, and effector, latent and activated Stat3 all undergo early autocrine and proteostatic deregulation, and intracellular sequestration and aggregation as a result of Ranbp2 loss in motoneurons. These effects were accompanied by paracrine and autocrine neuroglial deregulation of hnRNPH3 proteostasis in sciatic nerve and motoneurons, respectively, and post-transcriptional downregulation of metalloproteinase 28 in the sciatic nerve. Mechanistically, our results demonstrate that Ranbp2 controls nucleocytoplasmic, chemokine and metalloproteinase 28 signaling, and proteostasis of substrates that are crucial to motoneuronal homeostasis and whose impairments by loss of Ranbp2 drive ALS-like syndromes. Summary: Loss of Ranbp2 in spinal motoneurons drives ALS syndromes in mice and Ranbp2 functions in nucleocytoplasmic trafficking, proteostasis and chemokine signaling uncover novel therapeutic targets and mechanisms for motoneuron disease.
Collapse
Affiliation(s)
- Kyoung-In Cho
- Department of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
| | - Dosuk Yoon
- Department of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
| | - Sunny Qiu
- Department of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA
| | - Zachary Danziger
- Department of Biomedical Engineering, Duke University, Durham, NC 27710, USA
| | - Warren M Grill
- Department of Biomedical Engineering, Duke University, Durham, NC 27710, USA
| | - William C Wetsel
- Departments of Psychiatry and Behavioral Sciences, Cell Biology, and Neurobiology, Mouse Behavioral and Neuroendocrine Analysis Core Facility, Duke University Medical Center, Durham, NC 27710, USA
| | - Paulo A Ferreira
- Department of Ophthalmology, Duke University Medical Center, Durham, NC 27710, USA .,Department of Pathology, Duke University Medical Center, Durham, NC 27710, USA
| |
Collapse
|