1
|
Burato A, Legname G. Comparing Prion Proteins Across Species: Is Zebrafish a Useful Model? Mol Neurobiol 2024:10.1007/s12035-024-04324-z. [PMID: 38918277 DOI: 10.1007/s12035-024-04324-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2024] [Accepted: 06/19/2024] [Indexed: 06/27/2024]
Abstract
Despite the considerable body of research dedicated to the field of neurodegeneration, the gap in knowledge on the prion protein and its intricate involvement in brain diseases remains substantial. However, in the past decades, many steps forward have been taken toward a better understanding of the molecular mechanisms underlying both the physiological role of the prion protein and the misfolding event converting it into its pathological counterpart, the prion. This review aims to provide an overview of the main findings regarding this protein, highlighting the advantages of many different animal models that share a conserved amino acid sequence and/or structure with the human prion protein. A particular focus will be given to the species Danio rerio, a compelling research organism for the investigation of prion biology, thanks to its conserved orthologs, ease of genetic manipulation, and cost-effectiveness of high-throughput experimentation. We will explore its potential in filling some of the gaps on physiological and pathological aspects of the prion protein, with the aim of directing the future development of therapeutic interventions.
Collapse
Affiliation(s)
- Anna Burato
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore Di Studi Avanzati (SISSA), Trieste, Italy
| | - Giuseppe Legname
- Laboratory of Prion Biology, Department of Neuroscience, Scuola Internazionale Superiore Di Studi Avanzati (SISSA), Trieste, Italy.
| |
Collapse
|
2
|
Limone A, Maggisano V, Sarnataro D, Bulotta S. Emerging roles of the cellular prion protein (PrP C) and 37/67 kDa laminin receptor (RPSA) interaction in cancer biology. Cell Mol Life Sci 2023; 80:207. [PMID: 37452879 PMCID: PMC10349719 DOI: 10.1007/s00018-023-04844-2] [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: 05/10/2023] [Revised: 06/16/2023] [Accepted: 06/18/2023] [Indexed: 07/18/2023]
Abstract
The cellular prion protein (PrPC) is well-known for its involvement, under its pathogenic protease-resistant form (PrPSc), in a group of neurodegenerative diseases, known as prion diseases. PrPC is expressed in nervous system, as well as in other peripheral organs, and has been found overexpressed in several types of solid tumors. Notwithstanding, studies in recent years have disclosed an emerging role for PrPC in various cancer associated processes. PrPC has high binding affinity for 37/67 kDa laminin receptor (RPSA), a molecule that acts as a key player in tumorigenesis, affecting cell growth, adhesion, migration, invasion and cell death processes. Recently, we have characterized at cellular level, small molecules able to antagonize the direct PrPC binding to RPSA and their intracellular trafficking. These findings are very crucial considering that the main function of RPSA is to modulate key events in the metastasis cascade. Elucidation of the role played by PrPC/RPSA interaction in regulating tumor development, progression and response to treatment, represents a very promising challenge to gain pathogenetic information and discover novel specific biomarkers and/or therapeutic targets to be exploited in clinical settings. This review attempts to convey a detailed description of the complexity surrounding these multifaceted proteins from the perspective of cancer hallmarks, but with a specific focus on the role of their interaction in the control of proliferation, migration and invasion, genome instability and mutation, as well as resistance to cell death controlled by autophagic pathway.
Collapse
Affiliation(s)
- Adriana Limone
- Department of Molecular Medicine and Medical Biotechnology, University of Naples "Federico II", Via Pansini 5, 80131, Naples, Italy
| | - Valentina Maggisano
- Department of Health Sciences, University "Magna Graecia" of Catanzaro, Campus "S. Venuta", 88100, Catanzaro, Italy
| | - Daniela Sarnataro
- Department of Molecular Medicine and Medical Biotechnology, University of Naples "Federico II", Via Pansini 5, 80131, Naples, Italy.
| | - Stefania Bulotta
- Department of Health Sciences, University "Magna Graecia" of Catanzaro, Campus "S. Venuta", 88100, Catanzaro, Italy
| |
Collapse
|
3
|
Cellular Prion Protein Attenuates OGD/R-Induced Damage by Skewing Microglia toward an Anti-inflammatory State via Enhanced and Prolonged Activation of Autophagy. Mol Neurobiol 2023; 60:1297-1316. [PMID: 36441478 DOI: 10.1007/s12035-022-03099-5] [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: 05/04/2022] [Accepted: 10/21/2022] [Indexed: 11/29/2022]
Abstract
Modulation of microglial pro/anti-inflammatory states and autophagy are promising new therapies for ischemic stroke, but the underlying mechanisms remain largely unexplored. The objective of the study is to determine the intrinsic role of PrPC (cellular prion protein) in the regulation of microglial inflammatory states and autophagy in ischemic stroke. PrPC was expressed in murine microglia, and an in vitro oxygen-glucose deprivation/reperfusion (OGD/R) model was established in microglia of different PRNP genotypes. During reperfusion following OGD, wild-type (WT) microglia had significantly increased pro/anti-inflammatory microglial percentages and related cytokine [interleukin [IL]-6, IL-10, IL-4, tumor necrosis factor, and interferon-gamma] release at reperfusion after 48 or 72 h. WT microglia also showed greater accumulation of the autophagy markers LC3B-II/I (microtubule-associated protein B-light chain 3), but not of p62 or LAMP1 (lysosome-associated membrane protein) at reperfusion after 24 h and 48 h. Inhibition of autophagy using 3-methyladenine or bafilomycin A1 aggravated the OGD/R-induced pro-inflammatory state, and the effect of 3-methyladenine was significantly stronger than that of bafilomycin A1. Concomitantly, PRNP knockout shortened the accumulation of LC3B-II/I, suppressed microglial anti-inflammatory states, and further aggravated the pro-inflammatory states. Conversely, PRNP overexpression had the opposite effects. Bafilomycin A1 reversed the effect of PrPC on microglial inflammatory state transformation. Moreover, microglia with PRNP overexpression exhibited higher levels of LAMP1 expression in the control and OGD/R groups and delayed the OGD/R-induced decrease of LAMP1 to reperfusion after 48 h. PrPC attenuates OGD/R-induced damage by skewing microglia toward an anti-inflammatory state via enhanced and prolonged activation of autophagy.
Collapse
|
4
|
Armocida D, Busceti CL, Biagioni F, Fornai F, Frati A. The Role of Cellular Prion Protein in Glioma Tumorigenesis Could Be through the Autophagic Mechanisms: A Narrative Review. Int J Mol Sci 2023; 24:ijms24021405. [PMID: 36674920 PMCID: PMC9865539 DOI: 10.3390/ijms24021405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 12/12/2022] [Accepted: 12/22/2022] [Indexed: 01/13/2023] Open
Abstract
The carcinogenesis of glial tumors appears complex because of the many genetic and epigenetic phenomena involved. Among these, cellular prion protein (PrPC) is considered a key factor in cell-death resistance and important aspect implicated in tumorigenesis. Autophagy also plays an important role in cell death in various pathological conditions. These two cellular phenomena are related and share the same activation by specific alterations in the cellular microenvironment. Furthermore, there is an interdependence between autophagy and prion activity in glioma tumorigenesis. Glioma is one of the most aggressive known cancers, and the fact that such poorly studied processes as autophagy and PrPC activity are so strongly involved in its carcinogenesis suggests that by better understanding their interaction, more can be understood about its origin and treatment. Few studies in the literature relate these two cellular phenomena, much less try to explain their combined activity and role in glioma carcinogenesis. In this study, we explored the recent findings on the molecular mechanism and regulation pathways of autophagy, examining the role of PrPC in autophagy processes and how they may play a central role in glioma tumorigenesis. Among the many molecular interactions that PrP physiologically performs, it appears that processes shared with autophagy activity are those most implicated in glial tumor carcinogeneses such as activity on MAP kinases, PI3K, and mTOR. This work can be supportive and valuable as a basis for further future studies on this topic.
Collapse
Affiliation(s)
- Daniele Armocida
- Department of Human Neuroscience, Sapienza University of Rome, Via Caserta 6, 00161 Roma, Italy
- Department of Oral and Maxillofacial Sciences, Sapienza University of Rome, Via Caserta 6, 00161 Roma, Italy
- Istituto di Ricovero e Cura a Carattere Scientifico (I.R.C.C.S.) Neuromed, Via Atinense 18, 86077 Pozzilli, Italy
- Correspondence: ; Tel.: +39-39-3287-4496
| | - Carla Letizia Busceti
- Istituto di Ricovero e Cura a Carattere Scientifico (I.R.C.C.S.) Neuromed, Via Atinense 18, 86077 Pozzilli, Italy
| | - Francesca Biagioni
- Istituto di Ricovero e Cura a Carattere Scientifico (I.R.C.C.S.) Neuromed, Via Atinense 18, 86077 Pozzilli, Italy
| | - Francesco Fornai
- Istituto di Ricovero e Cura a Carattere Scientifico (I.R.C.C.S.) Neuromed, Via Atinense 18, 86077 Pozzilli, Italy
| | - Alessandro Frati
- Istituto di Ricovero e Cura a Carattere Scientifico (I.R.C.C.S.) Neuromed, Via Atinense 18, 86077 Pozzilli, Italy
| |
Collapse
|
5
|
A New Take on Prion Protein Dynamics in Cellular Trafficking. Int J Mol Sci 2020; 21:ijms21207763. [PMID: 33092231 PMCID: PMC7589859 DOI: 10.3390/ijms21207763] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 10/14/2020] [Accepted: 10/14/2020] [Indexed: 12/12/2022] Open
Abstract
The mobility of cellular prion protein (PrPC) in specific cell membrane domains and among distinct cell compartments dictates its molecular interactions and directs its cell function. PrPC works in concert with several partners to organize signaling platforms implicated in various cellular processes. The scaffold property of PrPC is able to gather a molecular repertoire to create heterogeneous membrane domains that favor endocytic events. Dynamic trafficking of PrPC through multiple pathways, in a well-orchestrated mechanism of intra and extracellular vesicular transport, defines its functional plasticity, and also assists the conversion and spreading of its infectious isoform associated with neurodegenerative diseases. In this review, we highlight how PrPC traffics across intra- and extracellular compartments and the consequences of this dynamic transport in governing cell functions and contributing to prion disease pathogenesis.
Collapse
|
6
|
Hara H, Sakaguchi S. N-Terminal Regions of Prion Protein: Functions and Roles in Prion Diseases. Int J Mol Sci 2020; 21:ijms21176233. [PMID: 32872280 PMCID: PMC7504422 DOI: 10.3390/ijms21176233] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 08/25/2020] [Accepted: 08/27/2020] [Indexed: 01/30/2023] Open
Abstract
The normal cellular isoform of prion protein, designated PrPC, is constitutively converted to the abnormally folded, amyloidogenic isoform, PrPSc, in prion diseases, which include Creutzfeldt-Jakob disease in humans and scrapie and bovine spongiform encephalopathy in animals. PrPC is a membrane glycoprotein consisting of the non-structural N-terminal domain and the globular C-terminal domain. During conversion of PrPC to PrPSc, its 2/3 C-terminal region undergoes marked structural changes, forming a protease-resistant structure. In contrast, the N-terminal region remains protease-sensitive in PrPSc. Reverse genetic studies using reconstituted PrPC-knockout mice with various mutant PrP molecules have revealed that the N-terminal domain has an important role in the normal function of PrPC and the conversion of PrPC to PrPSc. The N-terminal domain includes various characteristic regions, such as the positively charged residue-rich polybasic region, the octapeptide repeat (OR) region consisting of five repeats of an octapeptide sequence, and the post-OR region with another positively charged residue-rich polybasic region followed by a stretch of hydrophobic residues. We discuss the normal functions of PrPC, the conversion of PrPC to PrPSc, and the neurotoxicity of PrPSc by focusing on the roles of the N-terminal regions in these topics.
Collapse
|
7
|
López-Pérez Ó, Badiola JJ, Bolea R, Ferrer I, Llorens F, Martín-Burriel I. An Update on Autophagy in Prion Diseases. Front Bioeng Biotechnol 2020; 8:975. [PMID: 32984276 PMCID: PMC7481332 DOI: 10.3389/fbioe.2020.00975] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Accepted: 07/27/2020] [Indexed: 12/18/2022] Open
Abstract
Autophagy is a dynamic intracellular mechanism involved in protein and organelle turnover through lysosomal degradation. When properly regulated, autophagy supports normal cellular and developmental processes, whereas defects in autophagic degradation have been associated with several pathologies, including prion diseases. Prion diseases, or transmissible spongiform encephalopathies (TSE), are a group of fatal neurodegenerative disorders characterized by the accumulation of the pathological misfolded isoform (PrPSc) of the physiological cellular prion protein (PrPc) in the central nervous system. Autophagic vacuoles have been described in experimental models of TSE and in the natural disease in humans. The precise connection of this process with prion-related neuropathology, or even whether autophagy is completely beneficial or pathogenic during neurodegeneration, is poorly understood. Thus, the biological role of autophagy in these diseases is still open to debate. During the last years, researchers have used a wide range of morphological, genetic and biochemical methods to monitor and manipulate the autophagic pathway and thus determine the specific role of this process in TSE. It has been suggested that PrPc could play a crucial role in modulating the autophagic pathway in neuronal cells, and the presence of abnormal autophagic activity has been frequently observed in several models of TSE both in vitro and in vivo, as well as in human prion diseases. Altogether, these findings suggest that autophagy is implicated in prion neuropathology and points to an impairment or failure of the process, potentially contributing to the pathogenesis of the disease. Additionally, autophagy is now emerging as a host defense response in controlling prion infection that plays a protective role by facilitating the clearance of aggregation-prone proteins accumulated within neurons. Since autophagy is one of the pathways of PrPSc degradation, and drug-induced stimulation of autophagic flux (the dynamic process of autophagic degradation activity) produces anti-prion effects, new treatments based on its activation have been tested to develop therapeutic strategies for prion diseases. In this review, we summarize previous and recent findings concerning the role of autophagy in TSE.
Collapse
Affiliation(s)
- Óscar López-Pérez
- Laboratorio de Genética Bioquímica (LAGENBIO), Instituto Agroalimentario de Aragón-IA2, Instituto de Investigación Sanitaria Aragón-IISA, Universidad de Zaragoza, Zaragoza, Spain.,Centro de Encefalopatías y Enfermedades Transmisibles Emergentes (CEETE), Instituto Agroalimentario de Aragón-IA2, Instituto de Investigación Sanitaria Aragón-IISA, Universidad de Zaragoza, Zaragoza, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Instituto Carlos III, L'Hospitalet de Llobregat, Barcelona, Spain.,Instituto de Investigación Biomédica de Bellvitge (IDIBELL), L'Hospitalet de Llobregat, Barcelona, Spain
| | - Juan José Badiola
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes (CEETE), Instituto Agroalimentario de Aragón-IA2, Instituto de Investigación Sanitaria Aragón-IISA, Universidad de Zaragoza, Zaragoza, Spain
| | - Rosa Bolea
- Centro de Encefalopatías y Enfermedades Transmisibles Emergentes (CEETE), Instituto Agroalimentario de Aragón-IA2, Instituto de Investigación Sanitaria Aragón-IISA, Universidad de Zaragoza, Zaragoza, Spain
| | - Isidro Ferrer
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Instituto Carlos III, L'Hospitalet de Llobregat, Barcelona, Spain.,Instituto de Investigación Biomédica de Bellvitge (IDIBELL), L'Hospitalet de Llobregat, Barcelona, Spain.,Departamento de Patología y Terapéutica Experimental, Universidad de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Franc Llorens
- Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Instituto Carlos III, L'Hospitalet de Llobregat, Barcelona, Spain.,Instituto de Investigación Biomédica de Bellvitge (IDIBELL), L'Hospitalet de Llobregat, Barcelona, Spain.,Department of Neurology, Clinical Dementia Center and National Reference Center for CJD Surveillance, University Medical School, Göttingen, Germany
| | - Inmaculada Martín-Burriel
- Laboratorio de Genética Bioquímica (LAGENBIO), Instituto Agroalimentario de Aragón-IA2, Instituto de Investigación Sanitaria Aragón-IISA, Universidad de Zaragoza, Zaragoza, Spain.,Centro de Encefalopatías y Enfermedades Transmisibles Emergentes (CEETE), Instituto Agroalimentario de Aragón-IA2, Instituto de Investigación Sanitaria Aragón-IISA, Universidad de Zaragoza, Zaragoza, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Neurodegenerativas (CIBERNED), Instituto Carlos III, Zaragoza, Spain
| |
Collapse
|
8
|
"Dual Disease" TgAD/GSS mice exhibit enhanced Alzheimer's disease pathology and reveal PrP C-dependent secretion of Aβ. Sci Rep 2019; 9:8524. [PMID: 31189938 PMCID: PMC6562043 DOI: 10.1038/s41598-019-44317-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 03/13/2019] [Indexed: 12/30/2022] Open
Abstract
To address the question of cross-talk between prion protein (PrP) and Alzheimer's disease (AD), we generated TgAD/GSS mice that develop amyloid-β (Aβ) plaques of AD and PrP (specifically mutated PrPA116V) plaques of Gerstmann-Sträussler-Scheinker disease (GSS) and compared plaque-related features in these mice to AD mice that express normal (TgAD), high (TgAD/HuPrP), or no (TgAD/PrP-/-) PrPC. In contrast to PrPC, PrPA116V weakly co-localized to Aβ plaques, did not co-immunoprecipitate with Aβ, and poorly bound to Aβ in an ELISA-based binding assay. Despite the reduced association of PrPA116V with Aβ, TgAD/GSS and TgAD/HuPrP mice that express comparable levels of PrPA116V and PrPC respectively, displayed similar increases in Aβ plaque burden and steady state levels of Aβ and its precursor APP compared with TgAD mice. Our Tg mouse lines also revealed a predominance of intracellular Aβ plaques in mice lacking PrPC (TgAD/PrP-/-, TgAD/GSS) compared with an extracellular predominance in PrPC-expressing mice (TgAD, TgAD/HuPrP). Parallel studies in N2aAPPswe cells revealed a direct dependence on PrPC but not PrPA116V for exosome-related secretion of Aβ. Overall, our findings are two-fold; they suggest that PrP expression augments Aβ plaque production, at least in part by an indirect mechanism, perhaps by increasing steady state levels of APP, while they also provide support for a fundamental role of PrPC to bind to and deliver intraneuronal Aβ to exosomes for secretion.
Collapse
|
9
|
Jeong JK, Lee JH, Kim SW, Hong JM, Seol JW, Park SY. Cellular prion protein regulates the differentiation and function of adipocytes through autophagy flux. Mol Cell Endocrinol 2019; 481:84-94. [PMID: 30513342 DOI: 10.1016/j.mce.2018.11.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2018] [Revised: 11/06/2018] [Accepted: 11/23/2018] [Indexed: 02/06/2023]
Abstract
The role of autophagy modulation in adipogenic differentiation and the possible autophagy modulators targeting adipogenesis remain unclear. In this study, we investigated whether normal cellular prion protein (PrP<C>) is involved in the modulation of autophagy and affects adipogenic differentiation in vivo and in vitro. Surprisingly, autophagy flux signals were activated in the adipose tissue of prion protein-deficient mice and PrP<C>-deleted 3T3-L1 adipocytes. The activation of autophagy flux mediated by PrP<C> deletion was confirmed in the adipose tissue via transmission electron microscopy. Adipocyte differentiation factors were highly induced in prion protein-deficient adipose tissue and 3T3-L1 adipocytes. In addition, deletion of prion protein significantly increased visceral fat volume, body fat weight, adipocyte cell size, and body weight gain in Prnp-knockout mice and increased lipid accumulation in PrP<C> siRNA-transfected 3T3-L1 cells. However, the overexpression of prion protein using adenovirus inhibited the autophagic flux signals, lipid accumulation, and the PPAR-γ and C/EBP-α mRNA and protein expression levels in comparison to those in the control cells. Our results demonstrated that deletion of normal prion protein accelerated adipogenic differentiation and lipid accumulation mediated via autophagy flux activation.
Collapse
Affiliation(s)
- Jae-Kyo Jeong
- Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Iksan, Jeonbuk, 54596, Republic of Korea
| | - Ju-Hee Lee
- Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Iksan, Jeonbuk, 54596, Republic of Korea
| | - Sung-Wook Kim
- Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Iksan, Jeonbuk, 54596, Republic of Korea
| | - Jeong-Min Hong
- Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Iksan, Jeonbuk, 54596, Republic of Korea
| | - Jae-Won Seol
- Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Iksan, Jeonbuk, 54596, Republic of Korea
| | - Sang-Youel Park
- Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Iksan, Jeonbuk, 54596, Republic of Korea.
| |
Collapse
|
10
|
Majumder P, Chakrabarti O. Lysosomal Quality Control in Prion Diseases. Mol Neurobiol 2017; 55:2631-2644. [PMID: 28421536 DOI: 10.1007/s12035-017-0512-8] [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: 11/15/2016] [Accepted: 04/04/2017] [Indexed: 11/28/2022]
Abstract
Prion diseases are transmissible, familial or sporadic. The prion protein (PrP), a normal cell surface glycoprotein, is ubiquitously expressed throughout the body. While loss of function of PrP does not elicit apparent phenotypes, generation of misfolded forms of the protein or its aberrant metabolic isoforms has been implicated in a number of neurodegenerative disorders such as scrapie, kuru, Creutzfeldt-Jakob disease, fatal familial insomnia, Gerstmann-Sträussler-Scheinker and bovine spongiform encephalopathy. These diseases are all phenotypically characterised by spongiform vacuolation of the adult brain, hence collectively termed as late-onset spongiform neurodegeneration. Misfolded form of PrP (PrPSc) and one of its abnormal metabolic isoforms (the transmembrane CtmPrP) are known to be disease-causing agents that lead to progressive loss of structure or function of neurons culminating in neuronal death. The aberrant forms of PrP utilise and manipulate the various intracellular quality control mechanisms during pathogenesis of these diseases. Amongst these, the lysosomal quality control machinery emerges as one of the primary targets exploited by the disease-causing isoforms of PrP. The autophagosomal-lysosomal degradation pathway is adversely affected in multiple ways in prion diseases and may hence be regarded as an important modulator of neurodegeneration. Some of the ESCRT pathway proteins have also been shown to be involved in the manifestation of disease phenotype. This review discusses the significance of the lysosomal quality control pathway in affecting transmissible and familial types of prion diseases.
Collapse
Affiliation(s)
- Priyanka Majumder
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Sector-1, Block-AF, Bidhannagar, Kolkata, West Bengal, 700064, India
| | - Oishee Chakrabarti
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Sector-1, Block-AF, Bidhannagar, Kolkata, West Bengal, 700064, India.
| |
Collapse
|
11
|
Castle AR, Gill AC. Physiological Functions of the Cellular Prion Protein. Front Mol Biosci 2017; 4:19. [PMID: 28428956 PMCID: PMC5382174 DOI: 10.3389/fmolb.2017.00019] [Citation(s) in RCA: 128] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Accepted: 03/22/2017] [Indexed: 01/09/2023] Open
Abstract
The prion protein, PrPC, is a small, cell-surface glycoprotein notable primarily for its critical role in pathogenesis of the neurodegenerative disorders known as prion diseases. A hallmark of prion diseases is the conversion of PrPC into an abnormally folded isoform, which provides a template for further pathogenic conversion of PrPC, allowing disease to spread from cell to cell and, in some circumstances, to transfer to a new host. In addition to the putative neurotoxicity caused by the misfolded form(s), loss of normal PrPC function could be an integral part of the neurodegenerative processes and, consequently, significant research efforts have been directed toward determining the physiological functions of PrPC. In this review, we first summarise important aspects of the biochemistry of PrPC before moving on to address the current understanding of the various proposed functions of the protein, including details of the underlying molecular mechanisms potentially involved in these functions. Over years of study, PrPC has been associated with a wide array of different cellular processes and many interacting partners have been suggested. However, recent studies have cast doubt on the previously well-established links between PrPC and processes such as stress-protection, copper homeostasis and neuronal excitability. Instead, the functions best-supported by the current literature include regulation of myelin maintenance and of processes linked to cellular differentiation, including proliferation, adhesion, and control of cell morphology. Intriguing connections have also been made between PrPC and the modulation of circadian rhythm, glucose homeostasis, immune function and cellular iron uptake, all of which warrant further investigation.
Collapse
|
12
|
Cellular Prion Protein Combined with Galectin-3 and -6 Affects the Infectivity Titer of an Endogenous Retrovirus Assayed in Hippocampal Neuronal Cells. PLoS One 2016; 11:e0167293. [PMID: 27936017 PMCID: PMC5147886 DOI: 10.1371/journal.pone.0167293] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2016] [Accepted: 11/11/2016] [Indexed: 11/19/2022] Open
Abstract
Prion diseases are infectious and fatal neurodegenerative diseases which require the cellular prion protein, PrPC, for development of diseases. The current study shows that the PrPC augments infectivity and plaque formation of a mouse endogenous retrovirus, MuLV. We have established four neuronal cell lines expressing mouse PrPC, PrP+/+; two express wild type PrPC (MoPrPwild) and the other two express mutant PrPC (MoPrPmut). Infection of neuronal cells from various PrP+/+ and PrP-/- (MoPrPKO) lines with MuLV yielded at least three times as many plaques in PrP+/+ than in PrP-/-. Furthermore, among the four PrP+/+ lines, one mutant line, P101L, had at least 2.5 times as many plaques as the other three PrP+/+ lines. Plaques in P101L were four times larger than those in other PrP+/+ lines. Colocalization of PrP and CAgag was seen in MuLV-infected PrP+/+ cells. In the PrP-MuLV interaction, the involvement of galectin-3 and -6 was observed by immunoprecipitation with antibody to PrPC. These results suggest that PrPC combined with galectin-3 and -6 can act as a receptor for MuLV. P101L, the disease form of mutant PrPC results suggest the genetic mutant form of PrPC may be more susceptible to viral infection.
Collapse
|
13
|
Mays CE, Soto C. The stress of prion disease. Brain Res 2016; 1648:553-560. [PMID: 27060771 DOI: 10.1016/j.brainres.2016.04.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Revised: 04/01/2016] [Accepted: 04/05/2016] [Indexed: 01/31/2023]
Abstract
Prion diseases are fatal neurodegenerative disorders that include scrapie of sheep, bovine spongiform encephalopathy of cattle, chronic wasting disease of cervids, and Creutzfeldt-Jakob disease (CJD) of humans. The etiology for prion diseases can be infectious, sporadic, or hereditary. However, the common denominator for all types is the formation of a transmissible agent composed of a β-sheet-rich, misfolded version of the host-encoded prion protein (PrPC), known as PrPSc. PrPSc self-replicates through a template-assisted process that converts the α-helical conformation of PrPC into the disease-associated isoform. In parallel with PrPSc accumulation, spongiform change is pathologically observed in the central nervous system, where "holes" appear because of massive neuronal death. Here, we review the cellular pathways triggered in response to PrPSc formation and accumulation. Available data suggest that neuronal dysfunction and death may be caused by what originates as a cellular pro-survival response to chronic PrPSc accumulation. We also discuss what is known about the complex cross-talk between the endoplasmic reticulum stress components and the quality control pathways. Better knowledge about these processes may lead to innovative therapeutic strategies based on manipulating the stress response and its consequences for neurodegeneration. This article is part of a Special Issue entitled SI:ER stress.
Collapse
Affiliation(s)
- Charles E Mays
- Mitchell Center for Alzheimer's Disease and Related Brain Disorders, Department of Neurology, University of Texas Houston Medical School, Houston, TX 77030, USA
| | - Claudio Soto
- Mitchell Center for Alzheimer's Disease and Related Brain Disorders, Department of Neurology, University of Texas Houston Medical School, Houston, TX 77030, USA.
| |
Collapse
|
14
|
Dias MVS, Teixeira BL, Rodrigues BR, Sinigaglia-Coimbra R, Porto-Carreiro I, Roffé M, Hajj GNM, Martins VR. PRNP/prion protein regulates the secretion of exosomes modulating CAV1/caveolin-1-suppressed autophagy. Autophagy 2016; 12:2113-2128. [PMID: 27629560 DOI: 10.1080/15548627.2016.1226735] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Prion protein modulates many cellular functions including the secretion of trophic factors by astrocytes. Some of these factors are found in exosomes, which are formed within multivesicular bodies (MVBs) and secreted into the extracellular space to modulate cell-cell communication. The mechanisms underlying exosome biogenesis were not completely deciphered. Here, we demonstrate that primary cultures of astrocytes and fibroblasts from prnp-null mice secreted lower levels of exosomes than wild-type cells. Furthermore, prnp-null astrocytes exhibited reduced MVB formation and increased autophagosome formation. The reconstitution of PRNP expression at the cell membrane restored exosome secretion in PRNP-deficient astrocytes, whereas macroautophagy/autophagy inhibition via BECN1 depletion reestablished exosome release in these cells. Moreover, the PRNP octapeptide repeat domain was necessary to promote exosome secretion and to impair the formation of the CAV1-dependent ATG12-ATG5 cytoplasmic complex that drives autophagosome formation. Accordingly, higher levels of CAV1 were found in lipid raft domains instead of in the cytoplasm in prnp-null cells. Collectively, these findings demonstrate that PRNP supports CAV1-suppressed autophagy to protect MVBs from sequestration into phagophores, thus facilitating exosome secretion.
Collapse
Affiliation(s)
- Marcos V S Dias
- a International Research Center , A.C. Camargo Cancer Center , São Paulo , Brazil , National Institute for Oncogenomics, INCITO
| | - Bianca L Teixeira
- a International Research Center , A.C. Camargo Cancer Center , São Paulo , Brazil , National Institute for Oncogenomics, INCITO
| | - Bruna R Rodrigues
- a International Research Center , A.C. Camargo Cancer Center , São Paulo , Brazil , National Institute for Oncogenomics, INCITO
| | | | | | - Martín Roffé
- a International Research Center , A.C. Camargo Cancer Center , São Paulo , Brazil , National Institute for Oncogenomics, INCITO
| | - Glaucia N M Hajj
- a International Research Center , A.C. Camargo Cancer Center , São Paulo , Brazil , National Institute for Oncogenomics, INCITO
| | - Vilma R Martins
- a International Research Center , A.C. Camargo Cancer Center , São Paulo , Brazil , National Institute for Oncogenomics, INCITO
| |
Collapse
|
15
|
Moon JH, Lee JH, Nazim UMD, Lee YJ, Seol JW, Eo SK, Lee JH, Park SY. Human prion protein-induced autophagy flux governs neuron cell damage in primary neuron cells. Oncotarget 2016; 7:29989-30002. [PMID: 27102156 PMCID: PMC5058658 DOI: 10.18632/oncotarget.8802] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2016] [Accepted: 04/13/2016] [Indexed: 01/09/2023] Open
Abstract
An unusual molecular structure of the prion protein, PrPsc is found only in mammals with transmissible prion diseases. Prion protein stands for either the infectious pathogen itself or a main component of it. Recent studies suggest that autophagy is one of the major functions that keep cells alive and has a protective effect against the neurodegeneration. In this study, we investigated that the effect of human prion protein on autophagy-lysosomal system of primary neuronal cells. The treatment of human prion protein induced primary neuron cell death and decreased both LC3-II and p62 protein amount indicating autophagy flux activation. Electron microscope pictures confirmed the autophagic flux activation in neuron cells treated with prion protein. Inhibition of autophagy flux using pharmacological and genetic tools prevented neuron cell death induced by human prion protein. Autophagy flux induced by prion protein is more activated in prpc expressing cells than in prpc silencing cells. These data demonstrated that prion protein-induced autophagy flux is involved in neuron cell death in prion disease and suggest that autophagy flux might play a critical role in neurodegenerative diseases including prion disease.
Collapse
Affiliation(s)
- Ji-Hong Moon
- Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Iksan, Jeonbuk, South Korea
| | - Ju-Hee Lee
- Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Iksan, Jeonbuk, South Korea
| | - Uddin MD Nazim
- Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Iksan, Jeonbuk, South Korea
| | - You-Jin Lee
- Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Iksan, Jeonbuk, South Korea
| | - Jae-Won Seol
- Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Iksan, Jeonbuk, South Korea
| | - Seong-Kug Eo
- Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Iksan, Jeonbuk, South Korea
| | - John-hwa Lee
- Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Iksan, Jeonbuk, South Korea
| | - Sang-Youel Park
- Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Iksan, Jeonbuk, South Korea
| |
Collapse
|
16
|
Abstract
Transmissible spongiform encephalopathies (TSEs), or prion diseases, are fatal neurodegenerative disorders characterised by long incubation period, short clinical duration, and transmissibility to susceptible species. Neuronal loss, spongiform changes, gliosis and the accumulation in the brain of the misfolded version of a membrane-bound cellular prion protein (PrP(C)), termed PrP(TSE), are diagnostic markers of these diseases. Compelling evidence links protein misfolding and its accumulation with neurodegenerative changes. Accordingly, several mechanisms of prion-mediated neurotoxicity have been proposed. In this paper, we provide an overview of the recent knowledge on the mechanisms of neuropathogenesis, the neurotoxic PrP species and the possible therapeutic approaches to treat these devastating disorders.
Collapse
|
17
|
Nyeste A, Bencsura P, Vida I, Hegyi Z, Homolya L, Fodor E, Welker E. Expression of the Prion Protein Family Member Shadoo Causes Drug Hypersensitivity That Is Diminished by the Coexpression of the Wild Type Prion Protein. J Biol Chem 2016; 291:4473-86. [PMID: 26721882 DOI: 10.1074/jbc.m115.679035] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Indexed: 11/06/2022] Open
Abstract
The prion protein (PrP) seems to exert both neuroprotective and neurotoxic activities. The toxic activities are associated with the C-terminal globular parts in the absence of the flexible N terminus, specifically the hydrophobic domain (HD) or the central region (CR). The wild type prion protein (PrP-WT), having an intact flexible part, exhibits neuroprotective qualities by virtue of diminishing many of the cytotoxic effects of these mutant prion proteins (PrPΔHD and PrPΔCR) when coexpressed. The prion protein family member Doppel, which possesses a three-dimensional fold similar to the C-terminal part of PrP, is also harmful to neuronal and other cells in various models, a phenotype that can also be eliminated by the coexpression of PrP-WT. In contrast, another prion protein family member, Shadoo (Sho), a natively disordered protein possessing structural features similar to the flexible N-terminal tail of PrP, exhibits PrP-WT-like protective properties. Here, we report that, contrary to expectations, Sho expression in SH-SY5Y or HEK293 cells induces the same toxic phenotype of drug hypersensitivity as PrPΔCR. This effect is exhibited in a dose-dependent manner and is also counteracted by the coexpression of PrP-WT. The opposing effects of Shadoo in different model systems revealed here may be explored to help discern the relationship of the various toxic activities of mutant PrPs with each other and the neurotoxic effects seen in neurodegenerative diseases, such as transmissible spongiform encephalopathy and Alzheimer disease.
Collapse
Affiliation(s)
- Antal Nyeste
- From the Institute of Biochemistry, Biological Research Center, Hungarian Academy of Sciences, H-6726 Szeged, Hungary
| | - Petra Bencsura
- the Research Centre for Natural Sciences, Hungarian Academy of Sciences, H-1117 Budapest, Hungary, and
| | - István Vida
- the Research Centre for Natural Sciences, Hungarian Academy of Sciences, H-1117 Budapest, Hungary, and the Institute of Chemistry, Eötvös Loránd University, H-1117 Budapest, Hungary
| | - Zoltán Hegyi
- the Research Centre for Natural Sciences, Hungarian Academy of Sciences, H-1117 Budapest, Hungary, and
| | - László Homolya
- the Research Centre for Natural Sciences, Hungarian Academy of Sciences, H-1117 Budapest, Hungary, and
| | - Elfrieda Fodor
- From the Institute of Biochemistry, Biological Research Center, Hungarian Academy of Sciences, H-6726 Szeged, Hungary
| | - Ervin Welker
- From the Institute of Biochemistry, Biological Research Center, Hungarian Academy of Sciences, H-6726 Szeged, Hungary, the Research Centre for Natural Sciences, Hungarian Academy of Sciences, H-1117 Budapest, Hungary, and
| |
Collapse
|
18
|
Milisav I, Šuput D, Ribarič S. Unfolded Protein Response and Macroautophagy in Alzheimer's, Parkinson's and Prion Diseases. Molecules 2015; 20:22718-56. [PMID: 26694349 PMCID: PMC6332363 DOI: 10.3390/molecules201219865] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2015] [Revised: 11/30/2015] [Accepted: 12/09/2015] [Indexed: 12/13/2022] Open
Abstract
Proteostasis are integrated biological pathways within cells that control synthesis, folding, trafficking and degradation of proteins. The absence of cell division makes brain proteostasis susceptible to age-related changes and neurodegeneration. Two key processes involved in sustaining normal brain proteostasis are the unfolded protein response and autophagy. Alzheimer’s disease (AD), Parkinson’s disease (PD) and prion diseases (PrDs) have different clinical manifestations of neurodegeneration, however, all share an accumulation of misfolded pathological proteins associated with perturbations in unfolded protein response and macroautophagy. While both the unfolded protein response and macroautophagy play an important role in the prevention and attenuation of AD and PD progression, only macroautophagy seems to play an important role in the development of PrDs. Macroautophagy and unfolded protein response can be modulated by pharmacological interventions. However, further research is necessary to better understand the regulatory pathways of both processes in health and neurodegeneration to be able to develop new therapeutic interventions.
Collapse
Affiliation(s)
- Irina Milisav
- Institute of Pathophysiology, Faculty of Medicine, Zaloška 4, Ljubljana SI-1000, Slovenia.
- Faculty of Health Sciences, Zdravstvena pot 5, SI-1000 Ljubljana, Slovenija.
| | - Dušan Šuput
- Institute of Pathophysiology, Faculty of Medicine, Zaloška 4, Ljubljana SI-1000, Slovenia.
| | - Samo Ribarič
- Institute of Pathophysiology, Faculty of Medicine, Zaloška 4, Ljubljana SI-1000, Slovenia.
| |
Collapse
|
19
|
Cingaram PKR, Nyeste A, Dondapati DT, Fodor E, Welker E. Prion Protein Does Not Confer Resistance to Hippocampus-Derived Zpl Cells against the Toxic Effects of Cu2+, Mn2+, Zn2+ and Co2+ Not Supporting a General Protective Role for PrP in Transition Metal Induced Toxicity. PLoS One 2015; 10:e0139219. [PMID: 26426582 PMCID: PMC4591282 DOI: 10.1371/journal.pone.0139219] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2015] [Accepted: 09/10/2015] [Indexed: 01/04/2023] Open
Abstract
The interactions of transition metals with the prion protein (PrP) are well-documented and characterized, however, there is no consensus on their role in either the physiology of PrP or PrP-related neurodegenerative disorders. PrP has been reported to protect cells from the toxic stimuli of metals. By employing a cell viability assay, we examined the effects of various concentrations of Cu2+, Zn2+, Mn2+, and Co2+ on Zpl (Prnp-/-) and ZW (Prnp+/+) hippocampus-derived mouse neuronal cells. Prnp-/- Zpl cells were more sensitive to all four metals than PrP-expressing Zw cells. However, when we introduced PrP or only the empty vector into Zpl cells, we could not discern any protective effect associated with the presence of PrP. This observation was further corroborated when assessing the toxic effect of metals by propidium-iodide staining and fluorescence activated cell sorting analysis. Thus, our results on this mouse cell culture model do not seem to support a strong protective role for PrP against transition metal toxicity and also emphasize the necessity of extreme care when comparing cells derived from PrP knock-out and wild type mice.
Collapse
Affiliation(s)
| | - Antal Nyeste
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
- Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
| | - Divya Teja Dondapati
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Elfrieda Fodor
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
| | - Ervin Welker
- Institute of Biochemistry, Biological Research Centre, Hungarian Academy of Sciences, Szeged, Hungary
- Research Centre for Natural Sciences, Hungarian Academy of Sciences, Budapest, Hungary
- * E-mail:
| |
Collapse
|
20
|
Jeong JK, Park SY. Neuroprotective effect of cellular prion protein (PrPC) is related with activation of alpha7 nicotinic acetylcholine receptor (α7nAchR)-mediated autophagy flux. Oncotarget 2015; 6:24660-74. [PMID: 26295309 PMCID: PMC4694786 DOI: 10.18632/oncotarget.4953] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2015] [Accepted: 06/28/2015] [Indexed: 01/08/2023] Open
Abstract
Activation of the alpha7 nicotinic acetylcholine receptor (α7nAchR) is regulated by prion protein (PrPC) expression and has a neuroprotective effect by modulating autophagic flux. In this study, we hypothesized that PrPC may regulate α7nAchR activation and that may prevent prion-related neurodegenerative diseases by regulating autophagic flux. PrP(106-126) treatment decreased α7nAchR expression and activation of autophagic flux. In addition, the α7nAchR activator PNU-282987 enhanced autophagic flux and protected neuron cells against PrP(106-126)-induced apoptosis. However, activation of autophagy and the protective effects of PNU-282987 were inhibited in PrPC knockout hippocampal neuron cells. In addition, PrPC knockout hippocampal neuron cells showed decreased α7nAchR expression levels. Adenoviral overexpression of PrPC in PrPC knockout hippocampal neuron cells resulted in activation of autophagic flux and inhibition of prion peptide-mediated cell death via α7nAchR activation. This is the first report demonstrating that activation of α7nAchR-mediated autophagic flux is regulated by PrPC, and that activation of α7nAchR regulated by PrPC expression may play a pivotal role in protection of neuron cells against prion peptide-induced neuron cell death by autophagy. These results suggest that α7nAchR-mediated autophagic flux may be involved in the pathogenesis of prion-related diseases and may be a therapeutic target for prion-related neurodegenerative diseases.
Collapse
Affiliation(s)
- Jae-Kyo Jeong
- Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Jeonju, Korea
- Department of Bioactive Material Sciences and Research Center of Bioactive Materials, Chonbuk National University, Jeonju, Korea
| | - Sang-Youel Park
- Biosafety Research Institute, College of Veterinary Medicine, Chonbuk National University, Jeonju, Korea
- Department of Bioactive Material Sciences and Research Center of Bioactive Materials, Chonbuk National University, Jeonju, Korea
| |
Collapse
|
21
|
Sakudo A, Onodera T. Prion protein (PrP) gene-knockout cell lines: insight into functions of the PrP. Front Cell Dev Biol 2015; 2:75. [PMID: 25642423 PMCID: PMC4295555 DOI: 10.3389/fcell.2014.00075] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Accepted: 12/22/2014] [Indexed: 11/13/2022] Open
Abstract
Elucidation of prion protein (PrP) functions is crucial to fully understand prion diseases. A major approach to studying PrP functions is the use of PrP gene-knockout (Prnp (-/-)) mice. So far, six types of Prnp (-/-) mice have been generated, demonstrating the promiscuous functions of PrP. Recently, other PrP family members, such as Doppel and Shadoo, have been found. However, information obtained from comparative studies of structural and functional analyses of these PrP family proteins do not fully reveal PrP functions. Recently, varieties of Prnp (-/-) cell lines established from Prnp (-/-) mice have contributed to the analysis of PrP functions. In this mini-review, we focus on Prnp (-/-) cell lines and summarize currently available Prnp (-/-) cell lines and their characterizations. In addition, we introduce the recent advances in the methodology of cell line generation with knockout or knockdown of the PrP gene. We also discuss how these cell lines have provided valuable insights into PrP functions and show future perspectives.
Collapse
Affiliation(s)
- Akikazu Sakudo
- Laboratory of Biometabolic Chemistry, Faculty of Medicine, School of Health Sciences, University of the Ryukyus Nishihara, Japan
| | - Takashi Onodera
- Research Center for Food Safety, School of Agricultural and Life Sciences, University of Tokyo Tokyo, Japan
| |
Collapse
|
22
|
Nah J, Pyo JO, Jung S, Yoo SM, Kam TI, Chang J, Han J, Soo A An S, Onodera T, Jung YK. BECN1/Beclin 1 is recruited into lipid rafts by prion to activate autophagy in response to amyloid β 42. Autophagy 2014; 9:2009-21. [PMID: 24145555 DOI: 10.4161/auto.26118] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Prion protein (PRNP) has been implicated in various types of neurodegenerative diseases. Although much is known about prion diseases, the function of cellular PRNP remains cryptic. Here, we show that PRNP mediates amyloid β1–42 (Aβ42)-induced autophagy activation through its interaction with BECN1. Treatment with Aβ42 enhanced autophagy flux in neuronal cells. Aβ42-induced autophagy activation, however, was impaired in prnp-knockout primary cortical neurons and Prnp-knockdown or prnp-knockout neuronal cells. Immunoprecipitation assays revealed that PRNP interacted with BECN1 via the BCL2-binding domain of BECN1. This interaction promoted the subcellular localization of BECN1 into lipid rafts of the plasma membrane and enhanced activity of PtdIns3K (whose catalytic subunit is termed PIK3C3, mammalian ortholog of yeast VPS34) in lipid rafts by generating PtdIns3P in response to Aβ42. Further, the levels of lipid rafts that colocalized with BECN1, decreased in the brains of aged C57BL/6 mice, as did PRNP. These results suggested that PRNP interacts with BECN1 to recruit the PIK3C3 complex into lipid rafts and thus activates autophagy in response to Aβ42, defining a novel role of PRNP in the regulation of autophagy.
Collapse
|
23
|
Shin HY, Park JH, Carp RI, Choi EK, Kim YS. Deficiency of prion protein induces impaired autophagic flux in neurons. Front Aging Neurosci 2014; 6:207. [PMID: 25202268 PMCID: PMC4142790 DOI: 10.3389/fnagi.2014.00207] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Accepted: 07/25/2014] [Indexed: 12/22/2022] Open
Abstract
Normal cellular prion protein (PrPC) is highly expressed in the central nervous system. The Zürich I Prnp-deficient mouse strain did not show an abnormal phenotype in initial studies, however, in later studies, deficits in exploratory behavior and short- and long-term memory have been revealed. In the present study, numerous autophagic vacuoles were found in neurons from Zürich I Prnp-deficient mice. The autophagic accumulation in the soma of cortical neurons in Zürich I Prnp-deficient mice was observed as early as 3 months of age, and in the hippocampal neurons at 6 months of age. Specifically, there is accumulation of electron dense pigments associated with autophagy in the neurons of Zürich I Prnp-deficient mice. Furthermore, autophagic accumulations were observed as early as 3 months of age in the CA3 region of hippocampal and cerebral cortical neuropils. The autophagic vacuoles increased with age in the hippocampus of Zürich I Prnp-deficient mice at a faster rate and to a greater extent than in normal C57BL/6J mice, whereas the cortex exhibited high levels that were maintained from 3 months old in Zürich I Prnp-deficient mice. The pigmented autophagic accumulation is due to the incompletely digested material from autophagic vacuoles. Furthermore, a deficiency in PrPC may disrupt the autophagic flux by inhibiting autophagosome-lysosomal fusion. Overall, our results provide insight into the protective role of PrPC in neurons, which may play a role in normal behavior and other brain functions.
Collapse
Affiliation(s)
- Hae-Young Shin
- Ilsong Institute of Life Science, Hallym University Anyang, Gyeonggi-do, South Korea
| | - Jeong-Ho Park
- Ilsong Institute of Life Science, Hallym University Anyang, Gyeonggi-do, South Korea
| | - Richard I Carp
- New York State Institute for Basic Research in Developmental Disabilities Staten Island, NY, USA
| | - Eun-Kyoung Choi
- Ilsong Institute of Life Science, Hallym University Anyang, Gyeonggi-do, South Korea ; Department of Biomedical Gerontology, Graduate School of Hallym University Chuncheon, Gangwon-do, South Korea
| | - Yong-Sun Kim
- Ilsong Institute of Life Science, Hallym University Anyang, Gyeonggi-do, South Korea ; Department of Microbiology, College of Medicine, Hallym University Chuncheon, Gangwon-do, South Korea
| |
Collapse
|
24
|
Cortes CJ, Qin K, Norstrom EM, Green WN, Bindokas VP, Mastrianni JA. Early Delivery of Misfolded PrP from ER to Lysosomes by Autophagy. Int J Cell Biol 2013; 2013:560421. [PMID: 24454378 PMCID: PMC3877647 DOI: 10.1155/2013/560421] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2013] [Accepted: 09/20/2013] [Indexed: 01/17/2023] Open
Abstract
Prion diseases are linked to the accumulation of a misfolded isoform (PrP(Sc)) of prion protein (PrP). Evidence suggests that lysosomes are degradation endpoints and sites of the accumulation of PrP(Sc). We questioned whether lysosomes participate in the early quality control of newly generated misfolded PrP. We found PrP carrying the disease-associated T182A mutation (Mut-PrP) was delivered to lysosomes in a Golgi-independent manner. Time-lapse live cell imaging revealed early formation and uptake of GFP-tagged Mut-PrP aggregates into LysoTracker labeled vesicles. Compared with Wt-PrP, Mut-PrP expression was associated with an elevation in several markers of the autophagy-lysosomal pathway, and it extensively colocalized with the autophagosome-specific marker, LC3B. In autophagy deficient (ATG5(-/-)) mouse embryonic fibroblasts, or in normal cells treated with the autophagy-inhibitor 3-MA, Mut-PrP colocalization with lysosomes was reduced to a similar extent. Additionally, 3-MA selectively impaired the degradation of insoluble Mut-PrP, resulting in an increase in protease-resistant PrP, whereas the induction of autophagy by rapamycin reduced it. These findings suggest that autophagy might function as a quality control mechanism to limit the accumulation of misfolded PrP that normally leads to the generation of PrP(Sc).
Collapse
Affiliation(s)
- Constanza J. Cortes
- Departments of Neurology, MC2030, The University of Chicago Pritzker School of Medicine, 5841 S. Maryland Avenue, Chicago, IL 60637, USA
| | - Kefeng Qin
- Departments of Neurology, MC2030, The University of Chicago Pritzker School of Medicine, 5841 S. Maryland Avenue, Chicago, IL 60637, USA
| | - Eric M. Norstrom
- Departments of Neurology, MC2030, The University of Chicago Pritzker School of Medicine, 5841 S. Maryland Avenue, Chicago, IL 60637, USA
| | - William N. Green
- Departments of Neurobiology, The University of Chicago Pritzker School of Medicine, Chicago, IL 60637, USA
| | - Vytautas P. Bindokas
- Departments of Neurobiology, The University of Chicago Pritzker School of Medicine, Chicago, IL 60637, USA
| | - James A. Mastrianni
- Departments of Neurology, MC2030, The University of Chicago Pritzker School of Medicine, 5841 S. Maryland Avenue, Chicago, IL 60637, USA
| |
Collapse
|
25
|
Nuvolone M, Kana V, Hutter G, Sakata D, Mortin-Toth SM, Russo G, Danska JS, Aguzzi A. SIRPα polymorphisms, but not the prion protein, control phagocytosis of apoptotic cells. ACTA ACUST UNITED AC 2013; 210:2539-52. [PMID: 24145514 PMCID: PMC3832919 DOI: 10.1084/jem.20131274] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Prnp(-/-) mice lack the prion protein PrP(C) and are resistant to prion infections, but variable phenotypes have been reported in Prnp(-/-) mice and the physiological function of PrP(C) remains poorly understood. Here we examined a cell-autonomous phenotype, inhibition of macrophage phagocytosis of apoptotic cells, previously reported in Prnp(-/-) mice. Using formal genetic, genomic, and immunological analyses, we found that the regulation of phagocytosis previously ascribed to PrP(C) is instead controlled by a linked locus encoding the signal regulatory protein α (Sirpa). These findings indicate that control of phagocytosis was previously misattributed to the prion protein and illustrate the requirement for stringent approaches to eliminate confounding effects of flanking genes in studies modeling human disease in gene-targeted mice. The plethora of seemingly unrelated functions attributed to PrP(C) suggests that additional phenotypes reported in Prnp(-/-) mice may actually relate to Sirpa or other genetic confounders.
Collapse
Affiliation(s)
- Mario Nuvolone
- Institute of Neuropathology, University Hospital of Zurich, CH-8091 Zurich, Switzerland
| | | | | | | | | | | | | | | |
Collapse
|
26
|
The Functional Role of Prion Protein (PrPC) on Autophagy. Pathogens 2013; 2:436-45. [PMID: 25437200 PMCID: PMC4235692 DOI: 10.3390/pathogens2030436] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 06/11/2013] [Accepted: 06/18/2013] [Indexed: 12/19/2022] Open
Abstract
Cellular prion protein (PrPC) plays an important role in the cellular defense against oxidative stress. However, the exact protective mechanism of PrPC is unclear. Autophagy is essential for survival, differentiation, development, and homeostasis in several organisms. Although the role that autophagy plays in neurodegenerative disease has yet to be established, it is clear that autophagy-induced cell death is observed in neurodegenerative disorders that exhibit protein aggregations. Moreover, autophagy can promote cell survival and cell death under various conditions. In this review, we describe the involvement of autophagy in prion disease and the effects of PrPC.
Collapse
|
27
|
A proautophagic antiviral role for the cellular prion protein identified by infection with a herpes simplex virus 1 ICP34.5 mutant. J Virol 2013; 87:5882-94. [PMID: 23487467 DOI: 10.1128/jvi.02559-12] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The cellular prion protein (PrP) often plays a cytoprotective role by regulating autophagy in response to cell stress. The stress of infection with intracellular pathogens can stimulate autophagy, and autophagic degradation of pathogens can reduce their replication and thus help protect the infected cells. PrP also restricts replication of several viruses, but whether this activity is related to an effect on autophagy is not known. Herpes simplex virus 1 (HSV-1) effectively counteracts autophagy through binding of its ICP34.5 protein to the cellular proautophagy protein beclin-1. Autophagy can reduce replication of an HSV-1 mutant, Δ68H, which is incapable of binding beclin-1. We found that deletion of PrP in mice complements the attenuation of Δ68H, restoring its capacity to replicate in the central nervous system (CNS) to wild-type virus levels after intracranial or corneal infection. Cultured primary astrocytes but not neurons derived from PrP(-/-) mice also complemented the attenuation of Δ68H, enabling Δ68H to replicate at levels equivalent to wild-type virus. Ultrastructural analysis showed that normal astrocytes exhibited an increase in the number of autophagosomes after infection with Δ68H compared with wild-type virus, but PrP(-/-) astrocytes failed to induce autophagy in response to Δ68H infection. Redistribution of EGFP-LC3 into punctae occurred more frequently in normal astrocytes infected with Δ68H than with wild-type virus, but not in PrP(-/-) astrocytes, corroborating the ultrastructural analysis results. Our results demonstrate that PrP is critical for inducing autophagy in astrocytes in response to HSV-1 infection and suggest that PrP positively regulates autophagy in the mouse CNS.
Collapse
|
28
|
Arena G, La Mendola D, Pappalardo G, Sóvágó I, Rizzarelli E. Interactions of Cu2+ with prion family peptide fragments: Considerations on affinity, speciation and coordination. Coord Chem Rev 2012. [DOI: 10.1016/j.ccr.2012.03.038] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
29
|
Oh JM, Choi EK, Carp RI, Kim YS. Oxidative stress impairs autophagic flux in prion protein-deficient hippocampal cells. Autophagy 2012; 8:1448-61. [PMID: 22889724 DOI: 10.4161/auto.21164] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
We previously reported that autophagy is upregulated in Prnp-deficient (Prnp ( 0/0) ) hippocampal neuronal cells in comparison to cellular prion protein (PrP (C) )-expressing (Prnp (+/+) ) control cells under conditions of serum deprivation. In this study, we determined whether a protective mechanism of PrP (C) is associated with autophagy using Prnp ( 0/0) hippocampal neuronal cells under hydrogen peroxide (H 2O 2)-induced oxidative stress. We found that Prnp ( 0/0) cells were more susceptible to oxidative stress than Prnp (+/+) cells in a dose- and time-dependent manner. In addition, we observed enhanced autophagy by immunoblotting, which detected the conversion of microtubule-associated protein 1 light chain 3 β (LC3B)-I to LC3B-II, and we observed increased punctate LC3B immunostaining in H 2O 2-treated Prnp ( 0/0) cells compared with H 2O 2-treated control cells. Interestingly, this enhanced autophagy was due to impaired autophagic flux in the H 2O 2-treated Prnp ( 0/0) cells, while the H 2O 2-treated Prnp (+/+) cells showed enhanced autophagic flux. Furthermore, caspase-dependent and independent apoptosis was observed when both cell lines were exposed to H 2O 2. Moreover, the inhibition of autophagosome formation by Atg7 siRNA revealed that increased autophagic flux in Prnp (+/+) cells contributes to the prosurvival effect of autophagy against H 2O 2 cytotoxicity. Taken together, our results provide the first experimental evidence that the deficiency of PrP (C) may impair autophagic flux via H 2O 2-induced oxidative stress.
Collapse
Affiliation(s)
- Jae-Min Oh
- Ilsong Institute of Life Science, Hallym University, Anyang, Korea
| | | | | | | |
Collapse
|
30
|
Park Y, Kim W, Kim AY, Choi HJ, Choi JK, Park N, Koh EK, Seo J, Koh YH. Normal prion protein in Drosophila enhances the toxicity of pathogenic polyglutamine proteins and alters susceptibility to oxidative and autophagy signaling modulators. Biochem Biophys Res Commun 2010; 404:638-45. [PMID: 21146501 DOI: 10.1016/j.bbrc.2010.12.030] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2010] [Accepted: 12/05/2010] [Indexed: 12/18/2022]
Abstract
To investigate the in vivo functions of normal prion protein (PrP) in Drosophila, we utilized characterized transgenic flies expressing ³(F)⁴-tagged mouse PrP (Mo-PrP³(F)⁴). The neurotoxicity of pathogenic Machado-Joseph Disease (MJD) glutamine (Q) 78 and 127Q proteins were enhanced by the co-expression of Mo-PrP³(F)⁴in the fly eyes, while the eyes of controls flies and flies expressing Mo-PrP³(F)⁴) alone or together with MJD-Q27 or 20Q proteins did not show any defect. Susceptibilities to H₂O₂, paraquat, and Dithiothreitol (DTT) were altered in Mo-PrP³(F)⁴ flies. In addition, Mo-PrP³(F)⁴ flies were significantly more susceptible to the perturbation of autophagy signaling by an autophagy inhibitor, 3-methyladenine (3-MA), and inducer, LiCl. Taken together, our data suggest that Mo-PrP³(F)⁴ may enhance the neurotoxicity of pathogenic Poly-Q proteins by perturbing oxidative and autophagy signaling.
Collapse
Affiliation(s)
- Yunwoong Park
- ILSONG Institute of Life Science, Hallym University, Anyang, Gyeonggi-do 431-060, Republic of Korea
| | | | | | | | | | | | | | | | | |
Collapse
|
31
|
Zhang C, Jackson AP, Zhang ZR, Han Y, Yu S, He RQ, Perrett S. Amyloid-like aggregates of the yeast prion protein ure2 enter vertebrate cells by specific endocytotic pathways and induce apoptosis. PLoS One 2010; 5. [PMID: 20824085 PMCID: PMC2932714 DOI: 10.1371/journal.pone.0012529] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2010] [Accepted: 07/08/2010] [Indexed: 11/23/2022] Open
Abstract
Background A number of amyloid diseases involve deposition of extracellular protein aggregates, which are implicated in mechanisms of cell damage and death. However, the mechanisms involved remain poorly understood. Methodology/Principal Findings Here we use the yeast prion protein Ure2 as a generic model to investigate how amyloid-like protein aggregates can enter mammalian cells and convey cytotoxicity. The effect of three different states of Ure2 protein (native dimer, protofibrils and mature fibrils) was tested on four mammalian cell lines (SH-SY5Y, MES23.5, HEK-293 and HeLa) when added extracellularly to the medium. Immunofluorescence using a polyclonal antibody against Ure2 showed that all three protein states could enter the four cell lines. In each case, protofibrils significantly inhibited the growth of the cells in a dose-dependent manner, fibrils showed less toxicity than protofibrils, while the native state had no effect on cell growth. This suggests that the structural differences between the three protein states lead to their different effects upon cells. Protofibrils of Ure2 increased membrane conductivity, altered calcium homeostasis, and ultimately induced apoptosis. The use of standard inhibitors suggested uptake into mammalian cells might occur via receptor-mediated endocytosis. In order to investigate this further, we used the chicken DT40 B cell line DKOR, which allows conditional expression of clathrin. Uptake into the DKOR cell-line was reduced when clathrin expression was repressed suggesting similarities between the mechanism of PrP uptake and the mechanism observed here for Ure2. Conclusions/Significance The results provide insight into the mechanisms by which amyloid aggregates may cause pathological effects in prion and amyloid diseases.
Collapse
Affiliation(s)
- Chen Zhang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
- Graduate University of the Chinese Academy of Sciences, Beijing, China
| | - Antony P. Jackson
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
| | - Zai-Rong Zhang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
- Graduate University of the Chinese Academy of Sciences, Beijing, China
| | - Yan Han
- Department of Neurobiology and the Sino-Japan Joint Laboratory of Neurodegenerative Diseases, Beijing Institute of Geriatrics, Xuanwu Hospital of the Capital University of Medical Sciences, Beijing, China
| | - Shun Yu
- Department of Neurobiology and the Sino-Japan Joint Laboratory of Neurodegenerative Diseases, Beijing Institute of Geriatrics, Xuanwu Hospital of the Capital University of Medical Sciences, Beijing, China
| | - Rong-Qiao He
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Sarah Perrett
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
- * E-mail:
| |
Collapse
|
32
|
Das D, Luo X, Singh A, Gu Y, Ghosh S, Mukhopadhyay CK, Chen SG, Sy MS, Kong Q, Singh N. Paradoxical role of prion protein aggregates in redox-iron induced toxicity. PLoS One 2010; 5:e11420. [PMID: 20625431 PMCID: PMC2897850 DOI: 10.1371/journal.pone.0011420] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2010] [Accepted: 06/07/2010] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Imbalance of iron homeostasis has been reported in sporadic Creutzfeldt-Jakob-disease (sCJD) affected human and scrapie infected animal brains, but the contribution of this phenotype to disease associated neurotoxicity is unclear. METHODOLOGY/PRINCIPAL FINDINGS Using cell models of familial prion disorders, we demonstrate that exposure of cells expressing normal prion protein (PrP(C)) or mutant PrP forms to a source of redox-iron induces aggregation of PrP(C) and specific mutant PrP forms. Initially this response is cytoprotective, but becomes increasingly toxic with time due to accumulation of PrP-ferritin aggregates. Mutant PrP forms that do not aggregate are not cytoprotective, and cells show signs of acute toxicity. Intracellular PrP-ferritin aggregates induce the expression of LC3-II, indicating stimulation of autophagy in these cells. Similar observations are noted in sCJD and scrapie infected hamster brains, lending credence to these results. Furthermore, phagocytosis of PrP-ferritin aggregates by astrocytes is cytoprotective, while culture in astrocyte conditioned medium (CM) shows no measurable effect. Exposure to H(2)O(2), on the other hand, does not cause aggregation of PrP, and cells show acute toxicity that is alleviated by CM. CONCLUSIONS/SIGNIFICANCE These observations suggest that aggregation of PrP in response to redox-iron is cytoprotective. However, subsequent co-aggregation of PrP with ferritin induces intracellular toxicity unless the aggregates are degraded by autophagosomes or phagocytosed by adjacent scavenger cells. H(2)O(2), on the other hand, does not cause aggregation of PrP, and induces toxicity through extra-cellular free radicals. Together with previous observations demonstrating imbalance of iron homeostasis in prion disease affected brains, these observations provide insight into the mechanism of neurotoxicity by redox-iron, and the role of PrP in this process.
Collapse
Affiliation(s)
- Dola Das
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Xiu Luo
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Ajay Singh
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Yaping Gu
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Soumya Ghosh
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio, United States of America
| | | | - Shu G. Chen
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Man-Sun Sy
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Qingzhong Kong
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio, United States of America
| | - Neena Singh
- Department of Pathology, Case Western Reserve University, Cleveland, Ohio, United States of America
| |
Collapse
|
33
|
Mehrpour M, Codogno P. Prion protein: From physiology to cancer biology. Cancer Lett 2009; 290:1-23. [PMID: 19674833 DOI: 10.1016/j.canlet.2009.07.009] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2009] [Revised: 07/10/2009] [Accepted: 07/13/2009] [Indexed: 12/26/2022]
Abstract
Prion protein (PrPc) was originally viewed solely as being involved in prion disease, but now several intriguing lines of evidence have emerged indicating that it plays a fundamental role not only in the nervous system, but also throughout the human body. PrPc is expressed most abundantly in the brain, but has also been detected in other non-neuronal tissues as diverse as lymphoid cells, lung, heart, kidney, gastrointestinal tract, muscle, and mammary glands. Recent data indicate that PrPc may be implicated in biology of glioblastoma, breast cancer, prostate and gastric cancer. Over expression of PrPc is correlated to the acquisition by tumor cells of a phenotype for resistance to cell death induced by TNF alpha and TRAIL or antitumor drugs such as paclitaxel and anthracyclines. PrPc may promote tumorigenesis, proliferation and G1/S transition in gastric cancer cells. This review revisits the physiological functions of PrPc, and its possible implications for cancer biology.
Collapse
|