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Brumbaugh J, Aguado BA, Lysaght T, Goldstein LSB. Human fetal tissue is critical for biomedical research. Stem Cell Reports 2023; 18:2300-2312. [PMID: 37977142 PMCID: PMC10724055 DOI: 10.1016/j.stemcr.2023.10.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 10/09/2023] [Accepted: 10/10/2023] [Indexed: 11/19/2023] Open
Abstract
Human fetal tissue and cells derived from fetal tissue are crucial for biomedical research. Fetal tissues and cells are used to study both normal development and developmental disorders. They are broadly applied in vaccine development and production. Further, research using cells from fetal tissue is instrumental for studying many infectious diseases, including a broad range of viruses. These widespread applications underscore the value of fetal tissue research and reflect an important point: cells derived from fetal tissues have capabilities that cells from other sources do not. In many cases, increased functionality of cells derived from fetal tissues arises from increased proliferative capacity, ability to survive in culture, and developmental potential that is attenuated in adult tissues. This review highlights important, representative applications of fetal tissue for science and medicine.
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Affiliation(s)
- Justin Brumbaugh
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado Boulder, Boulder, CO, USA; University of Colorado Cancer Center, Anschutz Medical Campus, Aurora, CO, USA; Charles C. Gates Center for Regenerative Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO, USA.
| | - Brian A Aguado
- Department of Bioengineering, University of California, San Diego, La Jolla, CA, USA; Sanford Consortium for Regenerative Medicine, La Jolla, CA, USA
| | - Tamra Lysaght
- Centre for Biomedical Ethics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Lawrence S B Goldstein
- Sanford Consortium for Regenerative Medicine, La Jolla, CA, USA; Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA, USA; Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
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2
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Valdes P, Henry KW, Fitzgerald MQ, Muralidharan K, Caldwell AB, Ramachandran S, Goldstein LSB, Mobley WC, Galasko DR, Subramaniam S. Limitations of the human iPSC-derived neuron model for early-onset Alzheimer's disease. Mol Brain 2023; 16:75. [PMID: 37924159 PMCID: PMC10623777 DOI: 10.1186/s13041-023-01063-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 10/07/2023] [Indexed: 11/06/2023] Open
Abstract
Non-familial Alzheimer's disease (AD) occurring before 65 years of age is commonly referred to as early-onset Alzheimer's disease (EOAD) and constitutes ~ 5-6% of all AD cases (Mendez et al. in Continuum 25:34-51, 2019). While EOAD exhibits the same clinicopathological changes such as amyloid plaques, neurofibrillary tangles (NFTs), brain atrophy, and cognitive decline (Sirkis et al. in Mol Psychiatry 27:2674-88, 2022; Caldwell et al. in Mol Brain 15:83, 2022) as observed in the more prevalent late-onset AD (LOAD), EOAD patients tend to have more severe cognitive deficits, including visuospatial, language, and executive dysfunction (Sirkis et al. in Mol Psychiatry 27:2674-88, 2022). Patient-derived induced pluripotent stem cells (iPSCs) have been used to model and study penetrative, familial AD (FAD) mutations in APP, PSEN1, and PSEN2 (Valdes et al. in Research Square 1-30, 2022; Caldwell et al. in Sci Adv 6:1-16, 2020) but have been seldom used for sporadic forms of AD that display more heterogeneous disease mechanisms. In this study, we sought to characterize iPSC-derived neurons from EOAD patients via RNA sequencing. A modest difference in expression profiles between EOAD patients and non-demented control (NDC) subjects resulted in a limited number of differentially expressed genes (DEGs). Based on this analysis, we provide evidence that iPSC-derived neuron model systems, likely due to the loss of EOAD-associated epigenetic signatures arising from iPSC reprogramming, may not be ideal models for studying sporadic AD.
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Affiliation(s)
- Phoebe Valdes
- Department of Bioengineering, University of California, La Jolla, San Diego, CA, USA
- Bioengineering Graduate Program, University of California, La Jolla, San Diego, CA, USA
| | - Kenneth W Henry
- Department of Cellular and Molecular Medicine, University of California, La Jolla, San Diego, CA, USA
- Sanford Consortium for Regenerative Medicine, La Jolla, CA, USA
| | - Michael Q Fitzgerald
- Department of Bioengineering, University of California, La Jolla, San Diego, CA, USA
- Bioengineering Graduate Program, University of California, La Jolla, San Diego, CA, USA
| | - Koushik Muralidharan
- Medical Scientist Training Program, University of California, La Jolla, San Diego, CA, USA
- School of Medicine, University of California, La Jolla, San Diego, CA, USA
| | - Andrew B Caldwell
- Department of Bioengineering, University of California, La Jolla, San Diego, CA, USA
| | | | - Lawrence S B Goldstein
- Department of Cellular and Molecular Medicine, University of California, La Jolla, San Diego, CA, USA
- Sanford Stem Cell Clinical Center, University of California, La Jolla, San Diego, CA, USA
| | - William C Mobley
- Department of Neurosciences, University of California, La Jolla, San Diego, CA, USA
| | - Douglas R Galasko
- Department of Neurosciences, University of California, La Jolla, San Diego, CA, USA
| | - Shankar Subramaniam
- Department of Bioengineering, University of California, La Jolla, San Diego, CA, USA.
- Department of Cellular and Molecular Medicine, University of California, La Jolla, San Diego, CA, USA.
- Department of Nanoengineering, University of California, La Jolla, San Diego, CA, USA.
- Department of Computer Science and Engineering, University of California, La Jolla, San Diego, CA, USA.
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3
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Young JE, Goldstein LSB. Human-Induced Pluripotent Stem Cell (hiPSC)-Derived Neurons and Glia for the Elucidation of Pathogenic Mechanisms in Alzheimer's Disease. Methods Mol Biol 2023; 2561:105-133. [PMID: 36399267 DOI: 10.1007/978-1-0716-2655-9_6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Alzheimer's disease (AD) is a common neurodegenerative disorder and a mechanistically complex disease. For the last decade, human models of AD using induced pluripotent stem cells (iPSCs) have emerged as a powerful way to understand disease pathogenesis in relevant human cell types. In this review, we summarize the state of the field and how this technology can apply to studies of both familial and sporadic studies of AD. We discuss patient-derived iPSCs, genome editing, differentiation of neural cell types, and three-dimensional organoids, and speculate on the future of this type of work for increasing our understanding of, and improving therapeutic development for, this devastating disease.
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Affiliation(s)
- Jessica E Young
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, WA, USA. .,Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA, USA.
| | - Lawrence S B Goldstein
- Department of Cellular and Molecular Medicine, Department of Neurosciences, UC San Diego, La Jolla, CA, USA.,Sanford Consortium for Regenerative Medicine, La Jolla, CA, USA
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Mertens J, Herdy JR, Traxler L, Schafer ST, Schlachetzki JCM, Böhnke L, Reid DA, Lee H, Zangwill D, Fernandes DP, Agarwal RK, Lucciola R, Zhou-Yang L, Karbacher L, Edenhofer F, Stern S, Horvath S, Paquola ACM, Glass CK, Yuan SH, Ku M, Szücs A, Goldstein LSB, Galasko D, Gage FH. Age-dependent instability of mature neuronal fate in induced neurons from Alzheimer's patients. Cell Stem Cell 2021; 28:1533-1548.e6. [PMID: 33910058 PMCID: PMC8423435 DOI: 10.1016/j.stem.2021.04.004] [Citation(s) in RCA: 98] [Impact Index Per Article: 32.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 02/17/2021] [Accepted: 04/02/2021] [Indexed: 12/12/2022]
Abstract
Sporadic Alzheimer's disease (AD) exclusively affects elderly people. Using direct conversion of AD patient fibroblasts into induced neurons (iNs), we generated an age-equivalent neuronal model. AD patient-derived iNs exhibit strong neuronal transcriptome signatures characterized by downregulation of mature neuronal properties and upregulation of immature and progenitor-like signaling pathways. Mapping iNs to longitudinal neuronal differentiation trajectory data demonstrated that AD iNs reflect a hypo-mature neuronal identity characterized by markers of stress, cell cycle, and de-differentiation. Epigenetic landscape profiling revealed an underlying aberrant neuronal state that shares similarities with malignant transformation and age-dependent epigenetic erosion. To probe for the involvement of aging, we generated rejuvenated iPSC-derived neurons that showed no significant disease-related transcriptome signatures, a feature that is consistent with epigenetic clock and brain ontogenesis mapping, which indicate that fibroblast-derived iNs more closely reflect old adult brain stages. Our findings identify AD-related neuronal changes as age-dependent cellular programs that impair neuronal identity.
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Affiliation(s)
- Jerome Mertens
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, USA; Neural Aging Laboratory, Institute of Molecular Biology, CMBI, Leopold-Franzens-University Innsbruck, Tyrol, Austria.
| | - Joseph R Herdy
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, USA; Neural Aging Laboratory, Institute of Molecular Biology, CMBI, Leopold-Franzens-University Innsbruck, Tyrol, Austria; Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
| | - Larissa Traxler
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, USA; Neural Aging Laboratory, Institute of Molecular Biology, CMBI, Leopold-Franzens-University Innsbruck, Tyrol, Austria
| | - Simon T Schafer
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Johannes C M Schlachetzki
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Lena Böhnke
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, USA; Neural Aging Laboratory, Institute of Molecular Biology, CMBI, Leopold-Franzens-University Innsbruck, Tyrol, Austria
| | - Dylan A Reid
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Hyungjun Lee
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Dina Zangwill
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Diana P Fernandes
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Ravi K Agarwal
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Raffaella Lucciola
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, USA
| | - Lucia Zhou-Yang
- Neural Aging Laboratory, Institute of Molecular Biology, CMBI, Leopold-Franzens-University Innsbruck, Tyrol, Austria
| | - Lukas Karbacher
- Neural Aging Laboratory, Institute of Molecular Biology, CMBI, Leopold-Franzens-University Innsbruck, Tyrol, Austria
| | - Frank Edenhofer
- Department of Genomics, Stem Cells & Regenerative Medicine, Institute of Molecular Biology, CMBI, Institute of Molecular Biology and CMBI, Leopold-Franzens-University Innsbruck, Tyrol, Austria
| | - Shani Stern
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, USA; Sagol Department of Neurobiology, Faculty of Natural Sciences, University of Haifa, Haifa, Israel
| | - Steve Horvath
- Department of Human Genetics, Department of Biostatistics, University of California, Los Angeles, Los Angeles, CA, USA
| | - Apua C M Paquola
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, USA; Lieber Institute for Brain Development, Baltimore, MD, USA
| | - Christopher K Glass
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA, USA
| | - Shauna H Yuan
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA; University of Minnesota, Twin Cities, Department of Neurology, Minneapolis, MN, USA
| | - Manching Ku
- Department of Pediatrics and Adolescent Medicine, Division of Pediatric Hematology and Oncology, Faculty of Medicine, Medical Center - University of Freiburg, Freiburg, Germany
| | - Attila Szücs
- Neuronal Cell Biology Research Group, Eötvös Loránd University, Budapest, Hungary
| | - Lawrence S B Goldstein
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA; Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA, USA; Sanford Consortium for Regenerative Medicine, La Jolla, CA, USA
| | - Douglas Galasko
- Department of Neurosciences, University of California, San Diego, La Jolla, CA, USA
| | - Fred H Gage
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, CA, USA.
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Affiliation(s)
- Lawrence S. B. Goldstein
- Lawrence S. B. Goldstein is a distinguished professor in the Department of Cellular and Molecular Medicine and in the Department of Neuroscience at the University of California, San Diego, CA, USA
| | - Robert N. Klein
- Robert N. Klein II is chairman of the Yes on Proposition 14 Campaign: Californians for Stem Cell Research, Treatments, and Cures Initiative
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Langness VF, van der Kant R, Das U, Wang L, Chaves RDS, Goldstein LSB. Cholesterol-lowering drugs reduce APP processing to Aβ by inducing APP dimerization. Mol Biol Cell 2020; 32:247-259. [PMID: 33296223 PMCID: PMC8098827 DOI: 10.1091/mbc.e20-05-0345] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Amyloid beta (Aβ) is a major component of amyloid plaques, which are a key pathological hallmark found in the brains of Alzheimer’s disease (AD) patients. We show that statins are effective at reducing Aβ in human neurons from nondemented control subjects, as well as subjects with familial AD and sporadic AD. Aβ is derived from amyloid precursor protein (APP) through sequential proteolytic cleavage by BACE1 and γ-secretase. While previous studies have shown that cholesterol metabolism regulates APP processing to Aβ, the mechanism is not well understood. We used iPSC-derived neurons and bimolecular fluorescence complementation assays in transfected cells to elucidate how altering cholesterol metabolism influences APP processing. Altering cholesterol metabolism using statins decreased the generation of sAPPβ and increased levels of full-length APP (flAPP), indicative of reduced processing of APP by BACE1. We further show that statins decrease flAPP interaction with BACE1 and enhance APP dimerization. Additionally, statin-induced changes in APP dimerization and APP-BACE1 are dependent on cholesterol binding to APP. Our data indicate that statins reduce Aβ production by decreasing BACE1 interaction with flAPP and suggest that this process may be regulated through competition between APP dimerization and APP cholesterol binding.
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Affiliation(s)
- Vanessa F Langness
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093.,Sanford Consortium for Regenerative Medicine, University of California, San Diego, La Jolla, CA 92037
| | - Rik van der Kant
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University, Amsterdam de Boelelaan 1087, 1081 HV Amsterdam, The Netherlands.,Alzheimer Center Amsterdam, Department of Neurology, Amsterdam Neuroscience, Amsterdam UMC, De Boelelaan 1118, 1081 HZ Amsterdam, The Netherlands
| | - Utpal Das
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093.,Sanford Consortium for Regenerative Medicine, University of California, San Diego, La Jolla, CA 92037
| | - Louie Wang
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093.,Sanford Consortium for Regenerative Medicine, University of California, San Diego, La Jolla, CA 92037
| | - Rodrigo Dos Santos Chaves
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093.,Sanford Consortium for Regenerative Medicine, University of California, San Diego, La Jolla, CA 92037
| | - Lawrence S B Goldstein
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093.,Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093.,Sanford Consortium for Regenerative Medicine, University of California, San Diego, La Jolla, CA 92037
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Temple S, Goldstein LSB. Why we need fetal tissue research. Science 2019; 363:207. [PMID: 30655416 DOI: 10.1126/science.aaw6299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Sally Temple
- Sally Temple is the scientific director of the Neural Stem Cell Institute, Rensselaer, NY, USA.
| | - Lawrence S B Goldstein
- Lawrence S. B. Goldstein is a professor in the Department of Cellular and Molecular Medicine at the University of California, San Diego, CA, USA and the scientific director of the Sanford Consortium for Regenerative Medicine.
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van der Kant R, Langness VF, Herrera CM, Williams DA, Fong LK, Leestemaker Y, Steenvoorden E, Rynearson KD, Brouwers JF, Helms JB, Ovaa H, Giera M, Wagner SL, Bang AG, Goldstein LSB. Cholesterol Metabolism Is a Druggable Axis that Independently Regulates Tau and Amyloid-β in iPSC-Derived Alzheimer's Disease Neurons. Cell Stem Cell 2019; 24:363-375.e9. [PMID: 30686764 PMCID: PMC6414424 DOI: 10.1016/j.stem.2018.12.013] [Citation(s) in RCA: 186] [Impact Index Per Article: 37.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 09/26/2018] [Accepted: 12/17/2018] [Indexed: 02/07/2023]
Abstract
Genetic, epidemiologic, and biochemical evidence suggests that predisposition to Alzheimer's disease (AD) may arise from altered cholesterol metabolism, although the molecular pathways that may link cholesterol to AD phenotypes are only partially understood. Here, we perform a phenotypic screen for pTau accumulation in AD-patient iPSC-derived neurons and identify cholesteryl esters (CE), the storage product of excess cholesterol, as upstream regulators of Tau early during AD development. Using isogenic induced pluripotent stem cell (iPSC) lines carrying mutations in the cholesterol-binding domain of APP or APP null alleles, we found that while CE also regulate Aβ secretion, the effects of CE on Tau and Aβ are mediated by independent pathways. Efficacy and toxicity screening in iPSC-derived astrocytes and neurons showed that allosteric activation of CYP46A1 lowers CE specifically in neurons and is well tolerated by astrocytes. These data reveal that CE independently regulate Tau and Aβ and identify a druggable CYP46A1-CE-Tau axis in AD.
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Affiliation(s)
- Rik van der Kant
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Amsterdam Neuroscience, VU University Amsterdam de Boelelaan 1087, 1081 HV Amsterdam, the Netherlands
| | - Vanessa F Langness
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Cheryl M Herrera
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Daniel A Williams
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Lauren K Fong
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Yves Leestemaker
- Oncode Institute and Department of Cell and Chemical Biology, Leiden University Medical Center, Einthovenweg 20, 2333 ZC Leiden, the Netherlands
| | - Evelyne Steenvoorden
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, the Netherlands
| | - Kevin D Rynearson
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jos F Brouwers
- Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, Utrecht University Yalelaan 2, 3584 CM Utrecht, the Netherlands
| | - J Bernd Helms
- Department of Biochemistry and Cell Biology, Faculty of Veterinary Medicine, Utrecht University Yalelaan 2, 3584 CM Utrecht, the Netherlands
| | - Huib Ovaa
- Oncode Institute and Department of Cell and Chemical Biology, Leiden University Medical Center, Einthovenweg 20, 2333 ZC Leiden, the Netherlands
| | - Martin Giera
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, the Netherlands
| | - Steven L Wagner
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA; Research Biologist, VA San Diego Healthcare System, La Jolla, CA 92161, USA
| | - Anne G Bang
- Conrad Prebys Center for Chemical Genomics, Sanford Burnham Prebys Medical Discovery Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Lawrence S B Goldstein
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Sanford Consortium for Regenerative Medicine, La Jolla, CA 92037, USA.
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Fong LK, Yang MM, Dos Santos Chaves R, Reyna SM, Langness VF, Woodruff G, Roberts EA, Young JE, Goldstein LSB. Full-length amyloid precursor protein regulates lipoprotein metabolism and amyloid-β clearance in human astrocytes. J Biol Chem 2018; 293:11341-11357. [PMID: 29858247 DOI: 10.1074/jbc.ra117.000441] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2017] [Revised: 05/11/2018] [Indexed: 02/05/2023] Open
Abstract
Mounting evidence suggests that alterations in cholesterol homeostasis are involved in Alzheimer's disease (AD) pathogenesis. Amyloid precursor protein (APP) or multiple fragments generated by proteolytic processing of APP have previously been implicated in the regulation of cholesterol metabolism. However, the physiological function of APP in regulating lipoprotein homeostasis in astrocytes, which are responsible for de novo cholesterol biosynthesis and regulation in the brain, remains unclear. To address this, here we used CRISPR/Cas9 genome editing to generate isogenic APP-knockout (KO) human induced pluripotent stem cells (hiPSCs) and differentiated them into human astrocytes. We found that APP-KO astrocytes have reduced cholesterol and elevated levels of sterol regulatory element-binding protein (SREBP) target gene transcripts and proteins, which were both downstream consequences of reduced lipoprotein endocytosis. To elucidate which APP fragments regulate cholesterol homeostasis and to examine whether familial AD mutations in APP affect lipoprotein metabolism, we analyzed an isogenic allelic series harboring the APP Swedish and APP V717F variants. Only astrocytes homozygous for the APP Swedish (APPSwe/Swe) mutation, which had reduced full-length APP (FL APP) due to increased β-secretase cleavage, recapitulated the APP-KO phenotypes. Astrocytic internalization of β-amyloid (Aβ), another ligand for low-density lipoprotein (LDL) receptors, was also impaired in APP-KO and APPSwe/Swe astrocytes. Finally, impairing cleavage of FL APP through β-secretase inhibition in APPSwe/Swe astrocytes reversed the LDL and Aβ endocytosis defects. In conclusion, FL APP is involved in the endocytosis of LDL receptor ligands and is required for proper cholesterol homeostasis and Aβ clearance in human astrocytes.
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Affiliation(s)
- Lauren K Fong
- Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, California 92093; Sanford Consortium for Regenerative Medicine, La Jolla, California 92093
| | - Max M Yang
- Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, California 92093; Sanford Consortium for Regenerative Medicine, La Jolla, California 92093
| | - Rodrigo Dos Santos Chaves
- Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, California 92093; Sanford Consortium for Regenerative Medicine, La Jolla, California 92093
| | - Sol M Reyna
- Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, California 92093; Sanford Consortium for Regenerative Medicine, La Jolla, California 92093
| | - Vanessa F Langness
- Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, California 92093; Sanford Consortium for Regenerative Medicine, La Jolla, California 92093
| | - Grace Woodruff
- Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, California 92093; Sanford Consortium for Regenerative Medicine, La Jolla, California 92093
| | - Elizabeth A Roberts
- Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, California 92093; Sanford Consortium for Regenerative Medicine, La Jolla, California 92093
| | - Jessica E Young
- Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, California 92093; Department of Pathology and Institute of Stem Cell and Regenerative Medicine, University of Washington, Seattle, Washington 98195
| | - Lawrence S B Goldstein
- Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, California 92093; Sanford Consortium for Regenerative Medicine, La Jolla, California 92093; Department of Neurosciences, University of California at San Diego, La Jolla, California 92093.
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Young JE, Fong LK, Frankowski H, Petsko GA, Small SA, Goldstein LSB. Stabilizing the Retromer Complex in a Human Stem Cell Model of Alzheimer's Disease Reduces TAU Phosphorylation Independently of Amyloid Precursor Protein. Stem Cell Reports 2018; 10:1046-1058. [PMID: 29503090 PMCID: PMC5919412 DOI: 10.1016/j.stemcr.2018.01.031] [Citation(s) in RCA: 67] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2017] [Revised: 01/25/2018] [Accepted: 01/26/2018] [Indexed: 12/22/2022] Open
Abstract
Developing effective therapeutics for complex diseases such as late-onset, sporadic Alzheimer’s disease (SAD) is difficult due to genetic and environmental heterogeneity in the human population and the limitations of existing animal models. Here, we used hiPSC-derived neurons to test a compound that stabilizes the retromer, a highly conserved multiprotein assembly that plays a pivotal role in trafficking molecules through the endosomal network. Using this human-specific system, we have confirmed previous data generated in murine models and show that retromer stabilization has a potentially beneficial effect on amyloid beta generation from human stem cell-derived neurons. We further demonstrate that manipulation of retromer complex levels within neurons affects pathogenic TAU phosphorylation in an amyloid-independent manner. Taken together, our work demonstrates that retromer stabilization is a promising candidate for therapeutic development in AD and highlights the advantages of testing novel compounds in a human-specific, neuronal system. A retromer stabilizing molecule reduces Aβ and phospho-TAU levels in human neurons The molecule reduces Aβ and pTau in both SAD and FAD cell lines Retromer stabilization reduces tau phosphorylation in an APP-independent manner Confirms studies in mice and highlights hiPSCs as a preclinical model
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Affiliation(s)
- Jessica E Young
- Department of Pathology, University of Washington, Seattle, WA 98109, USA; Institute of Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA 98109, USA.
| | - Lauren K Fong
- Department of Cellular and Molecular Medicine, University of California, San Diego, CA 92093, USA
| | - Harald Frankowski
- Department of Pathology, University of Washington, Seattle, WA 98109, USA; Institute of Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA 98109, USA
| | - Gregory A Petsko
- Appel Alzheimer's Disease Research Institute, Weill Cornell Medical College, New York, NY 10021, USA
| | - Scott A Small
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Department of Neurology, Columbia University, New York, NY 10032, USA
| | - Lawrence S B Goldstein
- Department of Cellular and Molecular Medicine, University of California, San Diego, CA 92093, USA; Sanford Consortium for Regenerative Medicine, University of California, San Diego, CA 92093, USA.
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11
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Panopoulos AD, D'Antonio M, Benaglio P, Williams R, Hashem SI, Schuldt BM, DeBoever C, Arias AD, Garcia M, Nelson BC, Harismendy O, Jakubosky DA, Donovan MKR, Greenwald WW, Farnam K, Cook M, Borja V, Miller CA, Grinstein JD, Drees F, Okubo J, Diffenderfer KE, Hishida Y, Modesto V, Dargitz CT, Feiring R, Zhao C, Aguirre A, McGarry TJ, Matsui H, Li H, Reyna J, Rao F, O'Connor DT, Yeo GW, Evans SM, Chi NC, Jepsen K, Nariai N, Müller FJ, Goldstein LSB, Izpisua Belmonte JC, Adler E, Loring JF, Berggren WT, D'Antonio-Chronowska A, Smith EN, Frazer KA. iPSCORE: A Resource of 222 iPSC Lines Enabling Functional Characterization of Genetic Variation across a Variety of Cell Types. Stem Cell Reports 2017; 8:1086-1100. [PMID: 28410642 PMCID: PMC5390244 DOI: 10.1016/j.stemcr.2017.03.012] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 03/08/2017] [Accepted: 03/13/2017] [Indexed: 11/18/2022] Open
Abstract
Large-scale collections of induced pluripotent stem cells (iPSCs) could serve as powerful model systems for examining how genetic variation affects biology and disease. Here we describe the iPSCORE resource: a collection of systematically derived and characterized iPSC lines from 222 ethnically diverse individuals that allows for both familial and association-based genetic studies. iPSCORE lines are pluripotent with high genomic integrity (no or low numbers of somatic copy-number variants) as determined using high-throughput RNA-sequencing and genotyping arrays, respectively. Using iPSCs from a family of individuals, we show that iPSC-derived cardiomyocytes demonstrate gene expression patterns that cluster by genetic background, and can be used to examine variants associated with physiological and disease phenotypes. The iPSCORE collection contains representative individuals for risk and non-risk alleles for 95% of SNPs associated with human phenotypes through genome-wide association studies. Our study demonstrates the utility of iPSCORE for examining how genetic variants influence molecular and physiological traits in iPSCs and derived cell lines.
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Affiliation(s)
- Athanasia D Panopoulos
- Gene Expression Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Matteo D'Antonio
- Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Paola Benaglio
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Roy Williams
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA; Center for Regenerative Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - Sherin I Hashem
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Bernhard M Schuldt
- Zentrum für Integrative Psychiatrie, Universitätsklinikum Schleswig-Holstein, 24105 Kiel, Germany
| | - Christopher DeBoever
- Bioinformatics and Systems Biology Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA
| | - Angelo D Arias
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Melvin Garcia
- Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Bradley C Nelson
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Olivier Harismendy
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Bioinformatics and Systems Biology Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA
| | - David A Jakubosky
- Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA
| | - Margaret K R Donovan
- Bioinformatics and Systems Biology Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA
| | - William W Greenwald
- Bioinformatics and Systems Biology Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA
| | - KathyJean Farnam
- Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Megan Cook
- Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Victor Borja
- Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Carl A Miller
- Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jonathan D Grinstein
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA
| | - Frauke Drees
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jonathan Okubo
- Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | | | - Yuriko Hishida
- Gene Expression Laboratory, Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Veronica Modesto
- Stem Cell Core, Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Carl T Dargitz
- Stem Cell Core, Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Rachel Feiring
- Stem Cell Core, Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | - Chang Zhao
- Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Aitor Aguirre
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Thomas J McGarry
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Hiroko Matsui
- Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - He Li
- Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Joaquin Reyna
- Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Fangwen Rao
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Daniel T O'Connor
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Gene W Yeo
- Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Sylvia M Evans
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Neil C Chi
- Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, CA 92093, USA
| | - Kristen Jepsen
- Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Naoki Nariai
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Franz-Josef Müller
- Zentrum für Integrative Psychiatrie, Universitätsklinikum Schleswig-Holstein, 24105 Kiel, Germany
| | - Lawrence S B Goldstein
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | | | - Eric Adler
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jeanne F Loring
- Center for Regenerative Medicine, The Scripps Research Institute, La Jolla, CA 92037, USA
| | - W Travis Berggren
- Stem Cell Core, Salk Institute for Biological Studies, La Jolla, CA 92037, USA
| | | | - Erin N Smith
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Kelly A Frazer
- Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA.
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12
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D'Antonio M, Woodruff G, Nathanson JL, D'Antonio-Chronowska A, Arias A, Matsui H, Williams R, Herrera C, Reyna SM, Yeo GW, Goldstein LSB, Panopoulos AD, Frazer KA. High-Throughput and Cost-Effective Characterization of Induced Pluripotent Stem Cells. Stem Cell Reports 2017; 8:1101-1111. [PMID: 28410643 PMCID: PMC5390243 DOI: 10.1016/j.stemcr.2017.03.011] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 03/10/2017] [Accepted: 03/13/2017] [Indexed: 12/19/2022] Open
Abstract
Reprogramming somatic cells to induced pluripotent stem cells (iPSCs) offers the possibility of studying the molecular mechanisms underlying human diseases in cell types difficult to extract from living patients, such as neurons and cardiomyocytes. To date, studies have been published that use small panels of iPSC-derived cell lines to study monogenic diseases. However, to study complex diseases, where the genetic variation underlying the disorder is unknown, a sizable number of patient-specific iPSC lines and controls need to be generated. Currently the methods for deriving and characterizing iPSCs are time consuming, expensive, and, in some cases, descriptive but not quantitative. Here we set out to develop a set of simple methods that reduce cost and increase throughput in the characterization of iPSC lines. Specifically, we outline methods for high-throughput quantification of surface markers, gene expression analysis of in vitro differentiation potential, and evaluation of karyotype with markedly reduced cost.
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Affiliation(s)
- Matteo D'Antonio
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Grace Woodruff
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jason L Nathanson
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | | | - Angelo Arias
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA
| | - Hiroko Matsui
- Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Roy Williams
- Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Cheryl Herrera
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Sol M Reyna
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Gene W Yeo
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Lawrence S B Goldstein
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA.
| | | | - Kelly A Frazer
- Department of Pediatrics, University of California, San Diego, La Jolla, CA 92093, USA; Institute for Genomic Medicine, University of California, San Diego, La Jolla, CA 92093, USA.
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13
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Woodruff G, Reyna SM, Dunlap M, Van Der Kant R, Callender JA, Young JE, Roberts EA, Goldstein LSB. Defective Transcytosis of APP and Lipoproteins in Human iPSC-Derived Neurons with Familial Alzheimer's Disease Mutations. Cell Rep 2016; 17:759-773. [PMID: 27732852 PMCID: PMC5796664 DOI: 10.1016/j.celrep.2016.09.034] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Revised: 07/22/2016] [Accepted: 09/12/2016] [Indexed: 12/16/2022] Open
Abstract
We investigated early phenotypes caused by familial Alzheimer's disease (fAD) mutations in isogenic human iPSC-derived neurons. Analysis of neurons carrying fAD PS1 or APP mutations introduced using genome editing technology at the endogenous loci revealed that fAD mutant neurons had previously unreported defects in the recycling state of endocytosis and soma-to-axon transcytosis of APP and lipoproteins. The endocytosis reduction could be rescued through treatment with a β-secretase inhibitor. Our data suggest that accumulation of β-CTFs of APP, but not Aβ, slow vesicle formation from an endocytic recycling compartment marked by the transcytotic GTPase Rab11. We confirm previous results that endocytosis is affected in AD and extend these to uncover a neuron-specific defect. Decreased lipoprotein endocytosis and transcytosis to the axon suggest that a neuron-specific impairment in endocytic axonal delivery of lipoproteins and other key materials might compromise synaptic maintenance in fAD.
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Affiliation(s)
- Grace Woodruff
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Sol M Reyna
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Mariah Dunlap
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Rik Van Der Kant
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Julia A Callender
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jessica E Young
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Elizabeth A Roberts
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Lawrence S B Goldstein
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA; Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA; Sanford Consortium for Regenerative Medicine, University of California, San Diego, La Jolla, CA 92093, USA.
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14
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Abstract
Amyloid precursor protein (APP) is a key player in Alzheimer's disease (AD). The Aβ fragments of APP are the major constituent of AD-associated amyloid plaques, and mutations or duplications of the gene coding for APP can cause familial AD. Here we review the roles of APP in neuronal development, signaling, intracellular transport, and other aspects of neuronal homeostasis. We suggest that APP acts as a signaling nexus that transduces information about a range of extracellular conditions, including neuronal damage, to induction of intracellular signaling events. Subtle disruptions of APP signaling functions may be major contributors to AD-causing neuronal dysfunction.
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Affiliation(s)
- Rik van der Kant
- Department of Cellular and Molecular Medicine, University of California-San Diego, La Jolla, CA 92093, USA.
| | - Lawrence S B Goldstein
- Department of Cellular and Molecular Medicine, University of California-San Diego, La Jolla, CA 92093, USA.
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15
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Young JE, Boulanger-Weill J, Williams DA, Woodruff G, Buen F, Revilla AC, Herrera C, Israel MA, Yuan SH, Edland SD, Goldstein LSB. Elucidating molecular phenotypes caused by the SORL1 Alzheimer's disease genetic risk factor using human induced pluripotent stem cells. Cell Stem Cell 2015; 16:373-85. [PMID: 25772071 DOI: 10.1016/j.stem.2015.02.004] [Citation(s) in RCA: 117] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Revised: 01/11/2015] [Accepted: 02/10/2015] [Indexed: 12/20/2022]
Abstract
Predisposition to sporadic Alzheimer's disease (SAD) involves interactions between a person's unique combination of genetic variants and the environment. The molecular effect of these variants may be subtle and difficult to analyze with standard in vitro or in vivo models. Here we used hIPSCs to examine genetic variation in the SORL1 gene and possible contributions to SAD-related phenotypes in human neurons. We found that human neurons carrying SORL1 variants associated with an increased SAD risk show a reduced response to treatment with BDNF, at the level of both SORL1 expression and APP processing. shRNA knockdown of SORL1 demonstrates that the differences in BDNF-induced APP processing between genotypes are dependent on SORL1 expression. We propose that the variation in SORL1 expression induction by BDNF is modulated by common genetic variants and can explain how genetic variation in this one locus can contribute to an individual's risk of developing SAD.
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Affiliation(s)
- Jessica E Young
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Jonathan Boulanger-Weill
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Daniel A Williams
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Grace Woodruff
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Floyd Buen
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Arra C Revilla
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Cheryl Herrera
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Mason A Israel
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Shauna H Yuan
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Steven D Edland
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA; Division of Biostatistics, Department of Family and Preventive Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Lawrence S B Goldstein
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA.
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16
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Liu Q, Waltz S, Woodruff G, Ouyang J, Israel MA, Herrera C, Sarsoza F, Tanzi RE, Koo EH, Ringman JM, Goldstein LSB, Wagner SL, Yuan SH. Effect of potent γ-secretase modulator in human neurons derived from multiple presenilin 1-induced pluripotent stem cell mutant carriers. JAMA Neurol 2015; 71:1481-9. [PMID: 25285942 DOI: 10.1001/jamaneurol.2014.2482] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
IMPORTANCE Although considerable effort has been expended developing drug candidates for Alzheimer disease, none have yet succeeded owing to the lack of efficacy or to safety concerns. One potential shortcoming of current approaches to Alzheimer disease drug discovery and development is that they rely primarily on transformed cell lines and animal models that substantially overexpress wild-type or mutant proteins. It is possible that drug development failures thus far are caused in part by the limits of these approaches, which do not accurately reveal how drug candidates will behave in naive human neuronal cells. OBJECTIVE To analyze purified neurons derived from human induced pluripotent stem cells from patients carrying 3 different presenilin 1 (PS1) mutations and nondemented control individuals in the absence of any overexpression. We tested the efficacy of γ-secretase inhibitor and γ-secretase modulator (GSM) in neurons derived from both normal control and 3 PS1 mutations (A246E, H163R, and M146L). DESIGN, SETTING, AND PARTICIPANTS Adult human skin biopsies were obtained from volunteers at the Alzheimer Disease Research Center, University of California, San Diego. Cell cultures were treated with γ-secretase inhibitor or GSM. Comparisons of total β-amyloid (Aβ) and Aβ peptides 38, 40, and 42 in the media were made between vehicle- vs drug-treated cultures. MAIN OUTCOMES AND MEASURES Soluble Aβ levels in the media were measured by enzyme-linked immunosorbent assay. RESULTS As predicted, mutant PS1 neurons exhibited an elevated Aβ42:Aβ40 ratio (P < .05) at the basal state as compared with the nondemented control neurons. Treatment with a potent non-nonsteroidal anti-inflammatory druglike GSM revealed a new biomarker signature that differs from all previous cell types and animals tested. This new signature was the same in both the mutant and control neurons and consisted of a reduction in Aβ42, Aβ40, and Aβ38 and in the Aβ42:Aβ40 ratio, with no change in the total Aβ levels. CONCLUSIONS AND RELEVANCE This biomarker discrepancy is likely due to overexpression of amyloid precursor protein in the transformed cellular models. Our results suggest that biomarker signatures obtained with such models are misleading and that human neurons derived from human induced pluripotent stem cells provide a unique signature that will more accurately reflect drug response in human patients and in cerebrospinal fluid biomarker changes observed during GSM treatment.
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Affiliation(s)
- Qing Liu
- Department of Neurosciences, University of California, San Diego, La Jolla
| | - Shannon Waltz
- Department of Neurosciences, University of California, San Diego, La Jolla
| | - Grace Woodruff
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla
| | - Joe Ouyang
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla3Capitalbio, San Diego, California
| | - Mason A Israel
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla4Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, Texas
| | - Cheryl Herrera
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla
| | - Floyd Sarsoza
- Department of Neurosciences, University of California, San Diego, La Jolla
| | - Rudolph E Tanzi
- Genetics and Aging Research Unit, Department of Neurology, Massachusetts General Hospital, Charlestown
| | - Edward H Koo
- Department of Neurosciences, University of California, San Diego, La Jolla
| | - John M Ringman
- Mary S Easton Center for Alzheimer's Disease Research, Department of Neurology, University of California, Los Angeles
| | - Lawrence S B Goldstein
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla
| | - Steven L Wagner
- Department of Neurosciences, University of California, San Diego, La Jolla
| | - Shauna H Yuan
- Department of Neurosciences, University of California, San Diego, La Jolla
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17
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Weissmiller AM, Natera-Naranjo O, Reyna SM, Pearn ML, Zhao X, Nguyen P, Cheng S, Goldstein LSB, Tanzi RE, Wagner SL, Mobley WC, Wu C. A γ-secretase inhibitor, but not a γ-secretase modulator, induced defects in BDNF axonal trafficking and signaling: evidence for a role for APP. PLoS One 2015; 10:e0118379. [PMID: 25710492 PMCID: PMC4339551 DOI: 10.1371/journal.pone.0118379] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 01/14/2015] [Indexed: 11/19/2022] Open
Abstract
Clues to Alzheimer disease (AD) pathogenesis come from a variety of different sources including studies of clinical and neuropathological features, biomarkers, genomics and animal and cellular models. An important role for amyloid precursor protein (APP) and its processing has emerged and considerable interest has been directed at the hypothesis that Aβ peptides induce changes central to pathogenesis. Accordingly, molecules that reduce the levels of Aβ peptides have been discovered such as γ-secretase inhibitors (GSIs) and modulators (GSMs). GSIs and GSMs reduce Aβ levels through very different mechanisms. However, GSIs, but not GSMs, markedly increase the levels of APP CTFs that are increasingly viewed as disrupting neuronal function. Here, we evaluated the effects of GSIs and GSMs on a number of neuronal phenotypes possibly relevant to their use in treatment of AD. We report that GSI disrupted retrograde axonal trafficking of brain-derived neurotrophic factor (BDNF), suppressed BDNF-induced downstream signaling pathways and induced changes in the distribution within neuronal processes of mitochondria and synaptic vesicles. In contrast, treatment with a novel class of GSMs had no significant effect on these measures. Since knockdown of APP by specific siRNA prevented GSI-induced changes in BDNF axonal trafficking and signaling, we concluded that GSI effects on APP processing were responsible, at least in part, for BDNF trafficking and signaling deficits. Our findings argue that with respect to anti-amyloid treatments, even an APP-specific GSI may have deleterious effects and GSMs may serve as a better alternative.
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Affiliation(s)
- April M. Weissmiller
- Department of Neurosciences, University of California San Diego, San Diego, California, United States of America
| | - Orlangie Natera-Naranjo
- Department of Neurosciences, University of California San Diego, San Diego, California, United States of America
| | - Sol M. Reyna
- Department of Cellular and Molecular Medicine, University of California San Diego, San Diego, California, United States of America
| | - Matthew L. Pearn
- Department of Anesthesiology, University of California San Diego, San Diego, California, United States of America
- V.A. San Diego Healthcare System, San Diego, California, United States of America
| | - Xiaobei Zhao
- Department of Neurosciences, University of California San Diego, San Diego, California, United States of America
| | - Phuong Nguyen
- Department of Neurosciences, University of California San Diego, San Diego, California, United States of America
| | - Soan Cheng
- Department of Neurosciences, University of California San Diego, San Diego, California, United States of America
| | - Lawrence S. B. Goldstein
- Department of Cellular and Molecular Medicine, University of California San Diego, San Diego, California, United States of America
| | - Rudolph E. Tanzi
- Genetics and Aging Research Unit, Department of Neurology, Massachusetts General Hospital, Charlestown, Massachusetts, United States of America
| | - Steven L. Wagner
- Department of Neurosciences, University of California San Diego, San Diego, California, United States of America
| | - William C. Mobley
- Department of Neurosciences, University of California San Diego, San Diego, California, United States of America
| | - Chengbiao Wu
- Department of Neurosciences, University of California San Diego, San Diego, California, United States of America
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18
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Abstract
Our understanding of Alzheimer's disease (AD) is still incomplete and, as a result, we lack effective therapies. Reprogramming to generate human-induced pluripotent stem cells provides a new approach to the generation of human neurons that carry the genomes of people with familial or sporadic AD. Differentiation of such stem cells to human neurons is already providing new insights into AD and molecular pathways that may provide new targets for effective therapy. These pathways include typical amyloid response pathways, as well as pathways leading from altered behavior of amyloid precursor protein to the elevated phosphorylation of tau protein. There is also a need for standardization of models so that isogenic lines differing only in the familial AD mutation can be compared.
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Affiliation(s)
- Lawrence S B Goldstein
- Department of Cellular and Molecular Medicine, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA,
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19
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Abstract
In mouse and human neurons, axonally secreted amyloid precursor protein (APP) fragments are processed in the cell body before being sorted into the axon in a process that requires endocytosis for the processing, but not axonal delivery, of APP. Deposition of potentially neurotoxic Aβ fragments derived from amyloid precursor protein (APP) at synapses may be a key contributor to Alzheimer's disease. However, the location(s) of proteolytic processing and subsequent secretion of APP fragments from highly compartmentalized, euploid neurons that express APP and processing enzymes at normal levels is not well understood. To probe the behavior of endogenous APP, particularly in human neurons, we developed a system using neurons differentiated from human embryonic stem cells, cultured in microfluidic devices, to enable direct biochemical measurements from axons. Using human or mouse neurons in these devices, we measured levels of Aβ, sAPPα, and sAPPβ secreted solely from axons. We found that a majority of the fragments secreted from axons were processed in the soma, and many were dependent on somatic endocytosis for axonal secretion. We also observed that APP and the β-site APP cleaving enzyme were, for the most part, not dependent on endocytosis for axonal entry. These data establish that axonal entry and secretion of APP and its proteolytic processing products traverse different pathways in the somatodendritic compartment before axonal entry.
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Affiliation(s)
- Emily D Niederst
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Sol M Reyna
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093
| | - Lawrence S B Goldstein
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093
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20
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Neumann S, Campbell GE, Szpankowski L, Goldstein LSB, Encalada SE. Characterizing the composition of molecular motors on moving axonal cargo using "cargo mapping" analysis. J Vis Exp 2014:e52029. [PMID: 25406537 DOI: 10.3791/52029] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Understanding the mechanisms by which molecular motors coordinate their activities to transport vesicular cargoes within neurons requires the quantitative analysis of motor/cargo associations at the single vesicle level. The goal of this protocol is to use quantitative fluorescence microscopy to correlate ("map") the position and directionality of movement of live cargo to the composition and relative amounts of motors associated with the same cargo. "Cargo mapping" consists of live imaging of fluorescently labeled cargoes moving in axons cultured on microfluidic devices, followed by chemical fixation during recording of live movement, and subsequent immunofluorescence (IF) staining of the exact same axonal regions with antibodies against motors. Colocalization between cargoes and their associated motors is assessed by assigning sub-pixel position coordinates to motor and cargo channels, by fitting Gaussian functions to the diffraction-limited point spread functions representing individual fluorescent point sources. Fixed cargo and motor images are subsequently superimposed to plots of cargo movement, to "map" them to their tracked trajectories. The strength of this protocol is the combination of live and IF data to record both the transport of vesicular cargoes in live cells and to determine the motors associated to these exact same vesicles. This technique overcomes previous challenges that use biochemical methods to determine the average motor composition of purified heterogeneous bulk vesicle populations, as these methods do not reveal compositions on single moving cargoes. Furthermore, this protocol can be adapted for the analysis of other transport and/or trafficking pathways in other cell types to correlate the movement of individual intracellular structures with their protein composition. Limitations of this protocol are the relatively low throughput due to low transfection efficiencies of cultured primary neurons and a limited field of view available for high-resolution imaging. Future applications could include methods to increase the number of neurons expressing fluorescently labeled cargoes.
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Affiliation(s)
- Sylvia Neumann
- Department of Molecular and Experimental Medicine, Dorris Neuroscience Center, The Scripps Research Institute
| | - George E Campbell
- Department of Molecular and Experimental Medicine, Dorris Neuroscience Center, The Scripps Research Institute
| | - Lukasz Szpankowski
- Department of Cellular and Molecular Medicine, University of California San Diego; Department of Bioengineering, University of California San Diego
| | - Lawrence S B Goldstein
- Department of Cellular and Molecular Medicine, University of California San Diego; Department of Neurosciences, University of California San Diego School of Medicine
| | - Sandra E Encalada
- Department of Molecular and Experimental Medicine, Dorris Neuroscience Center, The Scripps Research Institute;
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21
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Abstract
Axonal transport is indispensable for the distribution of vesicles, organelles, messenger RNAs (mRNAs), and signaling molecules along the axon. This process is mediated by kinesins and dyneins, molecular motors that bind to cargoes and translocate on microtubule tracks. Tight modulation of motor protein activity is necessary, but little is known about the molecules and mechanisms that regulate transport. Moreover, evidence suggests that transport impairments contribute to the initiation or progression of neurodegenerative diseases, or both, but the mechanisms by which motor activity is affected in disease are unclear. In this review, we discuss some of the physical and biophysical properties that influence motor regulation in healthy neurons. We further discuss the evidence for the role of transport in neurodegeneration, highlighting two pathways that may contribute to transport impairment-dependent disease: genetic mutations or variation, and protein aggregation. Understanding how and when transport parameters change in disease will help delineate molecular mechanisms of neurodegeneration.
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Affiliation(s)
- Sandra E Encalada
- Department of Molecular and Experimental Medicine, Dorris Neuroscience Center, The Scripps Research Institute, La Jolla, California 92037;
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22
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Lu P, Woodruff G, Wang Y, Graham L, Hunt M, Wu D, Boehle E, Ahmad R, Poplawski G, Brock J, Goldstein LSB, Tuszynski MH. Long-distance axonal growth from human induced pluripotent stem cells after spinal cord injury. Neuron 2014; 83:789-96. [PMID: 25123310 DOI: 10.1016/j.neuron.2014.07.014] [Citation(s) in RCA: 258] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/07/2014] [Indexed: 12/28/2022]
Abstract
UNLABELLED Human induced pluripotent stem cells (iPSCs) from a healthy 86-year-old male were differentiated into neural stem cells and grafted into adult immunodeficient rats after spinal cord injury. Three months after C5 lateral hemisections, iPSCs survived and differentiated into neurons and glia and extended tens of thousands of axons from the lesion site over virtually the entire length of the rat CNS. These iPSC-derived axons extended through adult white matter of the injured spinal cord, frequently penetrating gray matter and forming synapses with rat neurons. In turn, host supraspinal motor axons penetrated human iPSC grafts and formed synapses. These findings indicate that intrinsic neuronal mechanisms readily overcome the inhibitory milieu of the adult injured spinal cord to extend many axons over very long distances; these capabilities persist even in neurons reprogrammed from very aged human cells. VIDEO ABSTRACT
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Affiliation(s)
- Paul Lu
- Veterans Administration Medical Center, San Diego, CA 92161, USA; Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA.
| | - Grace Woodruff
- Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Yaozhi Wang
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Lori Graham
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Matt Hunt
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Di Wu
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Eileen Boehle
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Ruhel Ahmad
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Gunnar Poplawski
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - John Brock
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Lawrence S B Goldstein
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA; Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Mark H Tuszynski
- Veterans Administration Medical Center, San Diego, CA 92161, USA; Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA.
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23
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Otero MG, Alloatti M, Cromberg LE, Almenar-Queralt A, Encalada SE, Pozo Devoto VM, Bruno L, Goldstein LSB, Falzone TL. Fast axonal transport of the proteasome complex depends on membrane interaction and molecular motor function. J Cell Sci 2014; 127:1537-49. [PMID: 24522182 DOI: 10.1242/jcs.140780] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Protein degradation by the ubiquitin-proteasome system in neurons depends on the correct delivery of the proteasome complex. In neurodegenerative diseases, aggregation and accumulation of proteins in axons link transport defects with degradation impairments; however, the transport properties of proteasomes remain unknown. Here, using in vivo experiments, we reveal the fast anterograde transport of assembled and functional 26S proteasome complexes. A high-resolution tracking system to follow fluorescent proteasomes revealed three types of motion: actively driven proteasome axonal transport, diffusive behavior in a viscoelastic axonema and proteasome-confined motion. We show that active proteasome transport depends on motor function because knockdown of the KIF5B motor subunit resulted in impairment of the anterograde proteasome flux and the density of segmental velocities. Finally, we reveal that neuronal proteasomes interact with intracellular membranes and identify the coordinated transport of fluorescent proteasomes with synaptic precursor vesicles, Golgi-derived vesicles, lysosomes and mitochondria. Taken together, our results reveal fast axonal transport as a new mechanism of proteasome delivery that depends on membrane cargo 'hitch-hiking' and the function of molecular motors. We further hypothesize that defects in proteasome transport could promote abnormal protein clearance in neurodegenerative diseases.
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Affiliation(s)
- Maria G Otero
- Instituto de Biología Celular y Neurociencias (UBA-CONICET), Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires CP 1121, Argentina
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24
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Woodruff G, Young JE, Martinez FJ, Buen F, Gore A, Kinaga J, Li Z, Yuan SH, Zhang K, Goldstein LSB. The presenilin-1 ΔE9 mutation results in reduced γ-secretase activity, but not total loss of PS1 function, in isogenic human stem cells. Cell Rep 2013; 5:974-85. [PMID: 24239350 DOI: 10.1016/j.celrep.2013.10.018] [Citation(s) in RCA: 140] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Revised: 09/06/2013] [Accepted: 10/10/2013] [Indexed: 12/16/2022] Open
Abstract
Presenilin 1 (PS1) is the catalytic core of γ-secretase, which cleaves type 1 transmembrane proteins, including the amyloid precursor protein (APP). PS1 also has γ-secretase-independent functions, and dominant PS1 missense mutations are the most common cause of familial Alzheimer's disease (FAD). Whether PS1 FAD mutations are gain- or loss-of-function remains controversial, primarily because most studies have relied on overexpression in mouse and/or nonneuronal systems. We used isogenic euploid human induced pluripotent stem cell lines to generate and study an allelic series of PS1 mutations, including heterozygous null mutations and homozygous and heterozygous FAD PS1 mutations. Rigorous analysis of this allelic series in differentiated, purified neurons allowed us to resolve this controversy and to conclude that FAD PS1 mutations, expressed at normal levels in the appropriate cell type, impair γ-secretase activity but do not disrupt γ-secretase-independent functions of PS1. Thus, FAD PS1 mutations do not act as simple loss of PS1 function but instead dominantly gain an activity toxic to some, but not all, PS1 functions.
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Affiliation(s)
- Grace Woodruff
- Department of Cellular and Molecular Medicine, Institute for Genomic Medicine and Institute of Engineering in Medicine, University of California, San Diego, La Jolla, CA 92093, USA
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25
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Almenar-Queralt A, Kim SN, Benner C, Herrera CM, Kang DE, Garcia-Bassets I, Goldstein LSB. Presenilins regulate neurotrypsin gene expression and neurotrypsin-dependent agrin cleavage via cyclic AMP response element-binding protein (CREB) modulation. J Biol Chem 2013; 288:35222-36. [PMID: 24145027 DOI: 10.1074/jbc.m113.513705] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Presenilins, the catalytic components of the γ-secretase complex, are upstream regulators of multiple cellular pathways via regulation of gene transcription. However, the underlying mechanisms and the genes regulated by these pathways are poorly characterized. In this study, we identify Tequila and its mammalian ortholog Prss12 as genes negatively regulated by presenilins in Drosophila larval brains and mouse embryonic fibroblasts, respectively. Prss12 encodes the serine protease neurotrypsin, which cleaves the heparan sulfate proteoglycan agrin. Altered neurotrypsin activity causes serious synaptic and cognitive defects; despite this, the molecular processes regulating neurotrypsin expression and activity are poorly understood. Using γ-secretase drug inhibitors and presenilin mutants in mouse embryonic fibroblasts, we found that a mature γ-secretase complex was required to repress neurotrypsin expression and agrin cleavage. We also determined that PSEN1 endoproteolysis or processing of well known γ-secretase substrates was not essential for this process. At the transcriptional level, PSEN1/2 removal induced cyclic AMP response element-binding protein (CREB)/CREB-binding protein binding, accumulation of activating histone marks at the neurotrypsin promoter, and neurotrypsin transcriptional and functional up-regulation that was dependent on GSK3 activity. Upon PSEN1/2 reintroduction, this active epigenetic state was replaced by a methyl CpG-binding protein 2 (MeCP2)-containing repressive state and reduced neurotrypsin expression. Genome-wide analysis revealed hundreds of other mouse promoters in which CREB binding is similarly modulated by the presence/absence of presenilins. Our study thus identifies Tequila and neurotrypsin as new genes repressed by presenilins and reveals a novel mechanism used by presenilins to modulate CREB signaling based on controlling CREB recruitment.
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26
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Duncan JE, Lytle NK, Zuniga A, Goldstein LSB. The Microtubule Regulatory Protein Stathmin Is Required to Maintain the Integrity of Axonal Microtubules in Drosophila. PLoS One 2013; 8:e68324. [PMID: 23840848 PMCID: PMC3694009 DOI: 10.1371/journal.pone.0068324] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Accepted: 05/22/2013] [Indexed: 12/25/2022] Open
Abstract
Axonal transport, a form of long-distance, bi-directional intracellular transport that occurs between the cell body and synaptic terminal, is critical in maintaining the function and viability of neurons. We have identified a requirement for the stathmin (stai) gene in the maintenance of axonal microtubules and regulation of axonal transport in Drosophila. The stai gene encodes a cytosolic phosphoprotein that regulates microtubule dynamics by partitioning tubulin dimers between pools of soluble tubulin and polymerized microtubules, and by directly binding to microtubules and promoting depolymerization. Analysis of stai function in Drosophila, which has a single stai gene, circumvents potential complications with studies performed in vertebrate systems in which mutant phenotypes may be compensated by genetic redundancy of other members of the stai gene family. This has allowed us to identify an essential function for stai in the maintenance of the integrity of axonal microtubules. In addition to the severe disruption in the abundance and architecture of microtubules in the axons of stai mutant Drosophila, we also observe additional neurological phenotypes associated with loss of stai function including a posterior paralysis and tail-flip phenotype in third instar larvae, aberrant accumulation of transported membranous organelles in stai deficient axons, a progressive bang-sensitive response to mechanical stimulation reminiscent of the class of Drosophila mutants used to model human epileptic seizures, and a reduced adult lifespan. Reductions in the levels of Kinesin-1, the primary anterograde motor in axonal transport, enhance these phenotypes. Collectively, our results indicate that stai has an important role in neuronal function, likely through the maintenance of microtubule integrity in the axons of nerves of the peripheral nervous system necessary to support and sustain long-distance axonal transport.
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Affiliation(s)
- Jason E. Duncan
- Department of Biology, Willamette University, Salem, Oregon, United States of America
- * E-mail:
| | - Nikki K. Lytle
- Department of Biology, Willamette University, Salem, Oregon, United States of America
| | - Alfredo Zuniga
- Department of Biology, Willamette University, Salem, Oregon, United States of America
| | - Lawrence S. B. Goldstein
- Howard Hughes Medical Institute, Department of Cellular and Molecular Medicine, School of Medicine, University of California San Diego, La Jolla, California, United States of America
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27
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Abstract
Neurons and other cells require intracellular transport of essential components for viability and function. Previous work has shown that while net amyloid precursor protein (APP) transport is generally anterograde, individual vesicles containing APP move bi-directionally. This discrepancy highlights our poor understanding of the in vivo regulation of APP-vesicle transport. Here, we show that reduction of presenilin (PS) or suppression of gamma-secretase activity substantially increases anterograde and retrograde velocities for APP vesicles. Strikingly, PS deficiency has no effect on an unrelated cargo vesicle class containing synaptotagmin, which is powered by a different kinesin motor. Increased velocities caused by PS or gamma-secretase reduction require functional kinesin-1 and dynein motors. Together, our findings suggest that a normal function of PS is to repress kinesin-1 and dynein motor activity during axonal transport of APP vesicles. Furthermore, our data suggest that axonal transport defects induced by loss of PS-mediated regulatory effects on APP-vesicle motility could be a major cause of neuronal and synaptic defects observed in Alzheimer's Disease (AD) pathogenesis. Thus, perturbations of APP/PS transport could contribute to early neuropathology observed in AD, and highlight a potential novel therapeutic pathway for early intervention, prior to neuronal loss and clinical manifestation of disease.
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28
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Abstract
Human pluripotent stem cells provide enormous opportunities to treat disease using cell therapy. But human stem cells can also drive biomedical and cell biological discoveries in a human model system, which can be directly linked to understanding disease or developing new therapies. Finally, rigorous scientific studies of these cells can and should inform the many science and medical policy issues that confront the translation of these technologies to medicine. In this paper, I discuss these issues using amyotrophic lateral sclerosis as an example.
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Affiliation(s)
- Lawrence S B Goldstein
- Department of Cellular and Molecular Medicine, University of California, San Diego School of Medicine, La Jolla, CA 92093, USA.
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29
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Weaver C, Leidel C, Szpankowski L, Farley NM, Shubeita GT, Goldstein LSB. Endogenous GSK-3/shaggy regulates bidirectional axonal transport of the amyloid precursor protein. Traffic 2013; 14:295-308. [PMID: 23279138 DOI: 10.1111/tra.12037] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2012] [Revised: 12/20/2012] [Accepted: 12/27/2012] [Indexed: 12/13/2022]
Abstract
Neurons rely on microtubule (MT) motor proteins such as kinesin-1 and dynein to transport essential cargos between the cell body and axon terminus. Defective axonal transport causes abnormal axonal cargo accumulations and is connected to neurodegenerative diseases, including Alzheimer's disease (AD). Glycogen synthase kinase 3 (GSK-3) has been proposed to be a central player in AD and to regulate axonal transport by the MT motor protein kinesin-1. Using genetic, biochemical and biophysical approaches in Drosophila melanogaster, we find that endogenous GSK-3 is a required negative regulator of both kinesin-1-mediated and dynein-mediated axonal transport of the amyloid precursor protein (APP), a key contributor to AD pathology. GSK-3 also regulates transport of an unrelated cargo, embryonic lipid droplets. By measuring the forces motors generate in vivo, we find that GSK-3 regulates transport by altering the activity of kinesin-1 motors but not their binding to the cargo. These findings reveal a new relationship between GSK-3 and APP, and demonstrate that endogenous GSK-3 is an essential in vivo regulator of bidirectional APP transport in axons and lipid droplets in embryos. Furthermore, they point to a new regulatory mechanism in which GSK-3 controls the number of active motors that are moving a cargo.
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Affiliation(s)
- Carole Weaver
- Department of Cellular and Molecular Medicine, School of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
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30
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Goff DJ, Court Recart A, Sadarangani A, Chun HJ, Barrett CL, Krajewska M, Leu H, Low-Marchelli J, Ma W, Shih AY, Wei J, Zhai D, Geron I, Pu M, Bao L, Chuang R, Balaian L, Gotlib J, Minden M, Martinelli G, Rusert J, Dao KH, Shazand K, Wentworth P, Smith KM, Jamieson CAM, Morris SR, Messer K, Goldstein LSB, Hudson TJ, Marra M, Frazer KA, Pellecchia M, Reed JC, Jamieson CHM. A Pan-BCL2 inhibitor renders bone-marrow-resident human leukemia stem cells sensitive to tyrosine kinase inhibition. Cell Stem Cell 2013; 12:316-28. [PMID: 23333150 DOI: 10.1016/j.stem.2012.12.011] [Citation(s) in RCA: 147] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2012] [Revised: 11/09/2012] [Accepted: 12/18/2012] [Indexed: 10/27/2022]
Abstract
Leukemia stem cells (LSCs) play a pivotal role in the resistance of chronic myeloid leukemia (CML) to tyrosine kinase inhibitors (TKIs) and its progression to blast crisis (BC), in part, through the alternative splicing of self-renewal and survival genes. To elucidate splice-isoform regulators of human BC LSC maintenance, we performed whole-transcriptome RNA sequencing, splice-isoform-specific quantitative RT-PCR (qRT-PCR), nanoproteomics, stromal coculture, and BC LSC xenotransplantation analyses. Cumulatively, these studies show that the alternative splicing of multiple prosurvival BCL2 family genes promotes malignant transformation of myeloid progenitors into BC LSCS that are quiescent in the marrow niche and that contribute to therapeutic resistance. Notably, sabutoclax, a pan-BCL2 inhibitor, renders marrow-niche-resident BC LSCs sensitive to TKIs at doses that spare normal progenitors. These findings underscore the importance of alternative BCL2 family splice-isoform expression in BC LSC maintenance and suggest that the combinatorial inhibition of prosurvival BCL2 family proteins and BCR-ABL may eliminate dormant LSCs and obviate resistance.
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Affiliation(s)
- Daniel J Goff
- Stem Cell Program, Department of Medicine, Moores Cancer Center, University of California San Diego, 3855 Health Sciences Drive, La Jolla, CA 92093, USA
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31
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Abstract
A crucial problem in liver disease biology and a major obstacle to the development of new therapies is the inability to conduct mechanistic studies of live human hepatocytes. Liver tissue from patients is difficult to obtain and only reveals the disease aftermath, while animal models lack the significant genetic diversity of humans. Monogenic metabolic disorders of the liver are an ideal platform to explore the complex gene-environment interactions and the role of genetic variation in the onset and progression of liver disease. Human induced pluripotent stem cell (hIPSC) technology provides an unprecedented opportunity to generate live cellular models of disease for therapeutic candidate discovery and cell replacement therapy. In this review, we discuss the potential of hIPSC to increase our understanding of human disease with a focus on the current efforts to model metabolic diseases of the liver and to generate suitable populations of human hepatocytes for cell transplantation.
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Affiliation(s)
- Maria Paulina Ordonez
- Department of Pediatric Gastroenterology, Hepatology and Nutrition, University of California, La Jolla, San Diego, CA 92093-0695, USA.
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32
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Abstract
The American Society for Cell Biology is targeting the first week of October 2012 (the week before Nobel Prize winners are announced) to launch the We Are Research initiative. The goal of this initiative is to mobilize practicing junior and senior scientists, including graduate students, postdocs, and other lab members, to make contact with their elected officials and neighbors and explain to them why Federal support and investment in biomedical research is vital to the health and economic welfare of the United States. This initiative is designed to illustrate how important people are to scientific research and to supply our representatives with reliable and accurate information in the form of letters, emails, telephone calls, and personal visits.
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Affiliation(s)
- Lawrence S B Goldstein
- Department of Cellular and Molecular Medicine and Department of Neurosciences, School of Medicine, University of California, San Diego, La Jolla, CA 92093, USA.
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33
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Abstract
Human pluripotent stem cells can differentiate into disease-relevant cell types, which capture the unique genome of an individual patient and provide insight into pathological mechanisms of human disease. Recently, human stem cell models for Alzheimer's disease (AD), the most common neurodegenerative dementia, have been described. Stem cell-derived neurons from patients with familial and sporadic AD and Down's syndrome recapitulate human disease phenotypes such as amyloid β peptide production, hyperphosphorylation of tau protein and endosomal abnormalities. Treatment of human neurons with small molecules can modulate these phenotypes, demonstrating the utility of this system for drug development and screening. This review will highlight the current AD stem cell models and discuss the remaining challenges and potential future directions of this field.
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Affiliation(s)
- Jessica E Young
- Department of Cellular and Molecular Medicine, USCD School of Medicine,9500 Gilman Drive, La Jolla, CA 92093, USA
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34
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Rodrigues EM, Weissmiller AM, Goldstein LSB. Enhanced β-secretase processing alters APP axonal transport and leads to axonal defects. Hum Mol Genet 2012; 21:4587-601. [PMID: 22843498 DOI: 10.1093/hmg/dds297] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Alzheimer's disease (AD) is a neurodegenerative disease pathologically characterized by amyloid plaques and neurofibrillary tangles in the brain. Before these hallmark features appear, signs of axonal transport defects develop, though the initiating events are not clear. Enhanced amyloidogenic processing of amyloid precursor protein (APP) plays an integral role in AD pathogenesis, and previous work suggests that both the Aβ region and the C-terminal fragments (CTFs) of APP can cause transport defects. However, it remains unknown if APP processing affects the axonal transport of APP itself, and whether increased APP processing is sufficient to promote axonal dystrophy. We tested the hypothesis that β-secretase cleavage site mutations of APP alter APP axonal transport directly. We found that the enhanced β-secretase cleavage reduces the anterograde axonal transport of APP, while inhibited β-cleavage stimulates APP anterograde axonal transport. Transport behavior of APP after treatment with β- or γ-secretase inhibitors suggests that the amount of β-secretase cleaved CTFs (βCTFs) of APP underlies these transport differences. Consistent with these findings, βCTFs have reduced anterograde axonal transport compared with full-length, wild-type APP. Finally, a gene-targeted mouse with familial AD (FAD) Swedish mutations to APP, which enhance the β-cleavage of APP, develops axonal dystrophy in the absence of mutant protein overexpression, amyloid plaque deposition and synaptic degradation. These results suggest that the enhanced β-secretase processing of APP can directly impair the anterograde axonal transport of APP and are sufficient to lead to axonal defects in vivo.
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Affiliation(s)
- Elizabeth M Rodrigues
- Division of Biological Sciences, University of California, San Diego, La Jolla, California 92093, USA
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35
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Abstract
Although it is well established that axonal transport defects are part of the initiation or progression of some neurodegenerative diseases, the precise role of these defects in disease development is poorly understood. Thus, in this article, rather than enumerate the already well-reviewed evidence that there are transport deficits in disease, I will focus on a discussion of two crucial and unanswered questions about the possible role of axonal transport defects in HD and AD. (1) Are alterations in axonal transport caused by changes in the normal function of proteins mutated or altered in HD and AD and/or do such alterations in transport occur as a result of the formation of toxic aggregates of peptides or proteins? (2) Do alterations in axonal transport contribute to the causes of HD and AD or are they early, or late, secondary consequences of other cellular defects caused by disease-induction?
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Affiliation(s)
- Lawrence S B Goldstein
- Department of Cellular and Molecular Medicine and Department of Neurosciences, UCSD School of Medicine, 9500 Gilman Drive, La Jolla, CA 92093-0695, USA.
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36
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Ordonez MP, Roberts EA, Kidwell CU, Yuan SH, Plaisted WC, Goldstein LSB. Disruption and therapeutic rescue of autophagy in a human neuronal model of Niemann Pick type C1. Hum Mol Genet 2012; 21:2651-62. [PMID: 22437840 DOI: 10.1093/hmg/dds090] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
An unresolved issue about many neurodegenerative diseases is why neurons are particularly sensitive to defects in ubiquitous cellular processes. One example is Niemann Pick type C1, caused by defects in cholesterol trafficking in all cells, but where neurons are preferentially damaged. Understanding this selective failure is limited by the difficulty in obtaining live human neurons from affected patients. To solve this problem, we generated neurons with decreased function of NPC1 from human embryonic stem cells and used them to test the hypothesis that defective cholesterol handling leads to enhanced pathological phenotypes in neurons. We found that human NPC1 neurons have strong spontaneous activation of autophagy, and, contrary to previous reports in patient fibroblasts, a block of autophagic progression leading to defective mitochondrial clearance. Mitochondrial fragmentation is an exceptionally severe phenotype in NPC1 neurons compared with fibroblasts, causing abnormal accumulation of mitochondrial proteins. Contrary to expectation, these abnormal phenotypes were rescued by treatment with the autophagy inhibitor 3-methyladenine and by treatment with the potential therapeutic cyclodextrin, which mobilizes cholesterol from the lysosomal compartment. Our findings suggest that neurons are especially sensitive to lysosomal cholesterol accumulation because of autophagy disruption and accumulation of fragmented mitochondria, thus defining a new route to effective drug development for NPC1 disease.
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Affiliation(s)
- M Paulina Ordonez
- Department of Cellular and Molecular Medicine, Howard Hughes Medical Institute, University of California San Diego, La Jolla, CA 92093, USA
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37
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Reis GF, Yang G, Szpankowski L, Weaver C, Shah SB, Robinson JT, Hays TS, Danuser G, Goldstein LSB. Molecular motor function in axonal transport in vivo probed by genetic and computational analysis in Drosophila. Mol Biol Cell 2012; 23:1700-14. [PMID: 22398725 PMCID: PMC3338437 DOI: 10.1091/mbc.e11-11-0938] [Citation(s) in RCA: 60] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Amyloid precursor protein (APP) vesicle movement by kinesin-1 and cytoplasmic dynein exhibits kinesin-1–dependent velocity. Our data also suggest that kinesin-1 and cytoplasmic dynein motors assemble in stable mixtures on APP vesicles and that their direction and velocity are controlled at least in part by dynein IC. Bidirectional axonal transport driven by kinesin and dynein along microtubules is critical to neuronal viability and function. To evaluate axonal transport mechanisms, we developed a high-resolution imaging system to track the movement of amyloid precursor protein (APP) vesicles in Drosophila segmental nerve axons. Computational analyses of a large number of moving vesicles in defined genetic backgrounds with partial reduction or overexpression of motor proteins enabled us to test with high precision existing and new models of motor activity and coordination in vivo. We discovered several previously unknown features of vesicle movement, including a surprising dependence of anterograde APP vesicle movement velocity on the amount of kinesin-1. This finding is largely incompatible with the biophysical properties of kinesin-1 derived from in vitro analyses. Our data also suggest kinesin-1 and cytoplasmic dynein motors assemble in stable mixtures on APP vesicles and their direction and velocity are controlled at least in part by dynein intermediate chain.
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Affiliation(s)
- Gerald F Reis
- Howard Hughes Medical Institute, University of California, San Diego, La Jolla, CA 92093, USA
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38
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Israel MA, Yuan SH, Bardy C, Reyna SM, Mu Y, Herrera C, Hefferan MP, Van Gorp S, Nazor KL, Boscolo FS, Carson CT, Laurent LC, Marsala M, Gage FH, Remes AM, Koo EH, Goldstein LSB. Probing sporadic and familial Alzheimer's disease using induced pluripotent stem cells. Nature 2012; 482:216-20. [PMID: 22278060 PMCID: PMC3338985 DOI: 10.1038/nature10821] [Citation(s) in RCA: 857] [Impact Index Per Article: 71.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2011] [Accepted: 01/04/2012] [Indexed: 02/06/2023]
Abstract
Our understanding of Alzheimer’s disease pathogenesis is currently limited by difficulties in obtaining live neurons from patients and the inability to model the sporadic form of the disease. It may be possible to overcome these challenges by reprogramming primary cells from patients into induced pluripotent stem cells (iPSCs). Here we reprogrammed primary fibroblasts from two patients with familial Alzheimer’s disease, both caused by a duplication of the amyloid-β precursor protein gene1 (APP; termed APPDp), two with sporadic Alzheimer’s disease (termed sAD1, sAD2) and two non-demented control individuals into iPSC lines. Neurons from differentiated cultures were purified with fluorescence-activated cell sorting and characterized. Purified cultures contained more than 90% neurons, clustered with fetal brain messenger RNA samples by microarray criteria, and could form functional synaptic contacts. Virtually all cells exhibited normal electrophysiological activity. Relative to controls, iPSC-derived, purified neurons from the two APPDp patients and patient sAD2 exhibited significantly higher levels of the pathological markers amyloid-β(1–40), phospho-tau(Thr 231) and active glycogen synthase kinase-3β (aGSK-3β). Neurons from APPDp and sAD2 patients also accumulated large RAB5-positive early endosomes compared to controls. Treatment of purified neurons with β-secretase inhibitors, but not γ-secretase inhibitors, caused significant reductions in phospho-Tau(Thr 231) and aGSK-3β levels. These results suggest a direct relationship between APP proteolytic processing, but not amyloid-β, in GSK-3β activation and tau phosphorylation in human neurons. Additionally, we observed that neurons with the genome of one sAD patient exhibited the phenotypes seen in familial Alzheimer’s disease samples. More generally, we demonstrate that iPSC technology can be used to observe phenotypes relevant to Alzheimer’s disease, even though it can take decades for overt disease to manifest in patients.
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Affiliation(s)
- Mason A Israel
- Howard Hughes Medical Institute and Department of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, California 92093, USA
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Killian RL, Flippin JD, Herrera CM, Almenar-Queralt A, Goldstein LSB. Kinesin light chain 1 suppression impairs human embryonic stem cell neural differentiation and amyloid precursor protein metabolism. PLoS One 2012; 7:e29755. [PMID: 22272245 PMCID: PMC3260181 DOI: 10.1371/journal.pone.0029755] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2011] [Accepted: 12/05/2011] [Indexed: 12/22/2022] Open
Abstract
The etiology of sporadic Alzheimer disease (AD) is largely unknown, although evidence implicates the pathological hallmark molecules amyloid beta (Aβ) and phosphorylated Tau. Work in animal models suggests that altered axonal transport caused by Kinesin-1 dysfunction perturbs levels of both Aβ and phosphorylated Tau in neural tissues, but the relevance of Kinesin-1 dependent functions to the human disease is unknown. To begin to address this issue, we generated human embryonic stem cells (hESC) expressing reduced levels of the kinesin light chain 1 (KLC1) Kinesin-1 subunit to use as a source of human neural cultures. Despite reduction of KLC1, undifferentiated hESC exhibited apparently normal colony morphology and pluripotency marker expression. Differentiated neural cultures derived from KLC1-suppressed hESC contained neural rosettes but further differentiation revealed obvious morphological changes along with reduced levels of microtubule-associated neural proteins, including Tau and less secreted Aβ, supporting the previously established connection between KLC1, Tau and Aβ. Intriguingly, KLC1-suppressed neural precursors (NPs), isolated using a cell surface marker signature known to identify cells that give rise to neurons and glia, unlike control cells, failed to proliferate. We suggest that KLC1 is required for normal human neural differentiation, ensuring proper metabolism of AD-associated molecules APP and Tau and for proliferation of NPs. Because impaired APP metabolism is linked to AD, this human cell culture model system will not only be a useful tool for understanding the role of KLC1 in regulating the production, transport and turnover of APP and Tau in neurons, but also in defining the essential function(s) of KLC1 in NPs and their progeny. This knowledge should have important implications for human neurodevelopmental and neurodegenerative diseases.
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Affiliation(s)
- Rhiannon L. Killian
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California, United States of America
- Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, California, United States of America
| | - Jessica D. Flippin
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California, United States of America
| | - Cheryl M. Herrera
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California, United States of America
| | - Angels Almenar-Queralt
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California, United States of America
- * E-mail: (LSBG); (AA-Q)
| | - Lawrence S. B. Goldstein
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California, United States of America
- Howard Hughes Medical Institute, University of California San Diego, La Jolla, California, United States of America
- * E-mail: (LSBG); (AA-Q)
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Abstract
I describe a number of valuable lessons I learned from participating in California's Proposition 71 effort about the role that scientists and rigorous scientific advice can play in a public political process. I describe how scientists can provide valuable information and advice and how they can also gain a great deal from the experience that is valuable to a practicing research scientist. Finally, I argue that in the future, building similar broad coalitions to support biomedical and other areas of scientific research will be essential to protect publicly funded science. Thus, a key lesson from the Proposition 71 experience is that engagement of scientists with diverse nonscientific groups can make a big difference and that scientists must actively engage with the public in the future if we are to contribute robustly to the medical and economic health of our communities.
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Affiliation(s)
- Lawrence S B Goldstein
- Howard Hughes Medical Institute, Department of Cellular and Molecular Medicine, School of Medicine, and UCSD Stem Cell Program, University of California, San Diego, La Jolla, CA 92093, USA.
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41
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Henthorn KS, Roux MS, Herrera C, Goldstein LSB. A role for kinesin heavy chain in controlling vesicle transport into dendrites in Drosophila. Mol Biol Cell 2011; 22:4038-46. [PMID: 21880894 PMCID: PMC3204066 DOI: 10.1091/mbc.e10-07-0572] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2010] [Revised: 07/11/2011] [Accepted: 08/25/2011] [Indexed: 12/02/2022] Open
Abstract
The unique architecture of neurons requires the establishment and maintenance of polarity, which relies in part on microtubule-based transport to deliver essential cargo into dendrites. To test different models of differential motor protein regulation and to understand how different compartments in neurons are supplied with necessary functional proteins, we studied mechanisms of dendritic transport, using Drosophila as a model system. Our data suggest that dendritic targeting systems in Drosophila and mammals are evolutionarily conserved, since mammalian cargoes are moved into appropriate domains in Drosophila. In a genetic screen for mutants that mislocalize the dendritic marker human transferrin receptor (hTfR), we found that kinesin heavy chain (KHC) may function as a dendritic motor. Our analysis of dendritic and axonal phenotypes of KHC loss-of-function clones revealed a role for KHC in maintaining polarity of neurons, as well as ensuring proper axonal outgrowth. In addition we identified adenomatous polyposis coli 1 (APC1) as an interaction partner of KHC in controlling directed transport and modulating kinesin function in neurons.
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Affiliation(s)
- Kristina Schimmelpfeng Henthorn
- Howard Hughes Medical Institute and Department of Cellular and Molecular Medicine, University of California, San Diego, School of Medicine, La Jolla, CA 92093-0683
| | - Meike Sabina Roux
- Department for Neuroanatomy and Molecular Brain Research, Ruhr-Universität Bochum, D-44780 Bochum, Germany
| | - Cheryl Herrera
- Howard Hughes Medical Institute and Department of Cellular and Molecular Medicine, University of California, San Diego, School of Medicine, La Jolla, CA 92093-0683
| | - Lawrence S. B. Goldstein
- Howard Hughes Medical Institute and Department of Cellular and Molecular Medicine, University of California, San Diego, School of Medicine, La Jolla, CA 92093-0683
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DeQuach JA, Yuan SH, Goldstein LSB, Christman KL. Decellularized porcine brain matrix for cell culture and tissue engineering scaffolds. Tissue Eng Part A 2011; 17:2583-92. [PMID: 21883047 DOI: 10.1089/ten.tea.2010.0724] [Citation(s) in RCA: 164] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The extracellular matrix (ECM) plays important roles in influencing cellular behavior such as attachment, differentiation, and proliferation. However, in conventional culture and tissue engineering strategies, single proteins are frequently utilized, which do not mimic the complex extracellular microenvironment seen in vivo. In this study we report a method to decellularize brain tissue using detergents. This decellularized brain matrix is rich in glycosaminoglycans and contains collagen I, collagen III, collagen IV, collagen V, collagen VI, perlecan, and laminin. By further processing the material into a liquid form, the brain matrix can be used as a cell culture coating. Neurons derived from human induced pluripotent stem cells plated on the brain matrix express neuronal markers and assume neuronal morphology. Additionally, the same material can potentially be used as a scaffold for tissue engineering as it reassembles upon injection in vivo to form a gel. Thus, our work demonstrates the ability to use decellularized brain ECM for cell culture and tissue engineering applications.
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Affiliation(s)
- Jessica A DeQuach
- Department of Bioengineering, University of California, San Diego, La Jolla, California 92092, USA
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43
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Encalada SE, Szpankowski L, Xia CH, Goldstein LSB. Stable kinesin and dynein assemblies drive the axonal transport of mammalian prion protein vesicles. Cell 2011; 144:551-65. [PMID: 21335237 DOI: 10.1016/j.cell.2011.01.021] [Citation(s) in RCA: 153] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2010] [Revised: 11/12/2010] [Accepted: 01/18/2011] [Indexed: 01/19/2023]
Abstract
Kinesin and dynein are opposite-polarity microtubule motors that drive the tightly regulated transport of a variety of cargoes. Both motors can bind to cargo, but their overall composition on axonal vesicles and whether this composition directly modulates transport activity are unknown. Here we characterize the intracellular transport and steady-state motor subunit composition of mammalian prion protein (PrP(C)) vesicles. We identify Kinesin-1 and cytoplasmic dynein as major PrP(C) vesicle motor complexes and show that their activities are tightly coupled. Regulation of normal retrograde transport by Kinesin-1 is independent of dynein-vesicle attachment and requires the vesicle association of a complete Kinesin-1 heavy and light chain holoenzyme. Furthermore, motor subunits remain stably associated with stationary as well as with moving vesicles. Our data suggest a coordination model wherein PrP(C) vesicles maintain a stable population of associated motors whose activity is modulated by regulatory factors instead of by structural changes to motor-cargo associations.
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Affiliation(s)
- Sandra E Encalada
- Department of Cellular and Molecular Medicine, School of Medicine, University of California, San Diego, La Jolla, 92093, USA.
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Yuan SH, Martin J, Elia J, Flippin J, Paramban RI, Hefferan MP, Vidal JG, Mu Y, Killian RL, Israel MA, Emre N, Marsala S, Marsala M, Gage FH, Goldstein LSB, Carson CT. Cell-surface marker signatures for the isolation of neural stem cells, glia and neurons derived from human pluripotent stem cells. PLoS One 2011; 6:e17540. [PMID: 21407814 PMCID: PMC3047583 DOI: 10.1371/journal.pone.0017540] [Citation(s) in RCA: 288] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2010] [Accepted: 02/08/2011] [Indexed: 12/22/2022] Open
Abstract
Background Neural induction of human pluripotent stem cells often yields heterogeneous cell populations that can hamper quantitative and comparative analyses. There is a need for improved differentiation and enrichment procedures that generate highly pure populations of neural stem cells (NSC), glia and neurons. One way to address this problem is to identify cell-surface signatures that enable the isolation of these cell types from heterogeneous cell populations by fluorescence activated cell sorting (FACS). Methodology/Principal Findings We performed an unbiased FACS- and image-based immunophenotyping analysis using 190 antibodies to cell surface markers on naïve human embryonic stem cells (hESC) and cell derivatives from neural differentiation cultures. From this analysis we identified prospective cell surface signatures for the isolation of NSC, glia and neurons. We isolated a population of NSC that was CD184+/CD271−/CD44−/CD24+ from neural induction cultures of hESC and human induced pluripotent stem cells (hiPSC). Sorted NSC could be propagated for many passages and could differentiate to mixed cultures of neurons and glia in vitro and in vivo. A population of neurons that was CD184−/CD44−/CD15LOW/CD24+ and a population of glia that was CD184+/CD44+ were subsequently purified from cultures of differentiating NSC. Purified neurons were viable, expressed mature and subtype-specific neuronal markers, and could fire action potentials. Purified glia were mitotic and could mature to GFAP-expressing astrocytes in vitro and in vivo. Conclusions/Significance These findings illustrate the utility of immunophenotyping screens for the identification of cell surface signatures of neural cells derived from human pluripotent stem cells. These signatures can be used for isolating highly pure populations of viable NSC, glia and neurons by FACS. The methods described here will enable downstream studies that require consistent and defined neural cell populations.
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Affiliation(s)
- Shauna H. Yuan
- Howard Hughes Medical Institute and Department of Cellular and Molecular Medicine, School of Medicine, University of California San Diego, La Jolla, California, United States of America
- Department of Neurosciences, School of Medicine, University of California San Diego, La Jolla, California, United States of America
| | - Jody Martin
- BD Biosciences, La Jolla, California, United States of America
| | - Jeanne Elia
- BD Biosciences, La Jolla, California, United States of America
| | - Jessica Flippin
- Howard Hughes Medical Institute and Department of Cellular and Molecular Medicine, School of Medicine, University of California San Diego, La Jolla, California, United States of America
| | | | - Mike P. Hefferan
- Anesthesiology Research Laboratory, Department of Anesthesiology, University of California San Diego, La Jolla, California, United States of America
| | - Jason G. Vidal
- BD Biosciences, La Jolla, California, United States of America
| | - Yangling Mu
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, California, United States of America
| | - Rhiannon L. Killian
- Howard Hughes Medical Institute and Department of Cellular and Molecular Medicine, School of Medicine, University of California San Diego, La Jolla, California, United States of America
- Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, California, United States of America
| | - Mason A. Israel
- Howard Hughes Medical Institute and Department of Cellular and Molecular Medicine, School of Medicine, University of California San Diego, La Jolla, California, United States of America
- Biomedical Sciences Graduate Program, University of California San Diego, La Jolla, California, United States of America
| | - Nil Emre
- BD Biosciences, La Jolla, California, United States of America
| | - Silvia Marsala
- Anesthesiology Research Laboratory, Department of Anesthesiology, University of California San Diego, La Jolla, California, United States of America
| | - Martin Marsala
- Anesthesiology Research Laboratory, Department of Anesthesiology, University of California San Diego, La Jolla, California, United States of America
- Institute of Neurobiology, Slovak Academy of Sciences, Košice, Slovakia
| | - Fred H. Gage
- Laboratory of Genetics, The Salk Institute for Biological Studies, La Jolla, California, United States of America
| | - Lawrence S. B. Goldstein
- Howard Hughes Medical Institute and Department of Cellular and Molecular Medicine, School of Medicine, University of California San Diego, La Jolla, California, United States of America
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45
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Falzone TL, Gunawardena S, McCleary D, Reis GF, Goldstein LSB. Kinesin-1 transport reductions enhance human tau hyperphosphorylation, aggregation and neurodegeneration in animal models of tauopathies. Hum Mol Genet 2010; 19:4399-408. [PMID: 20817925 DOI: 10.1093/hmg/ddq363] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Neurodegeneration induced by abnormal hyperphosphorylation and aggregation of the microtubule-associated protein tau defines neurodegenerative tauopathies. Destabilization of microtubules by loss of tau function and filament formation by toxic gain of function are two mechanisms suggested for how abnormal tau triggers neuronal loss. Recent experiments in kinesin-1 deficient mice suggested that axonal transport defects can initiate biochemical changes that induce activation of axonal stress kinase pathways leading to abnormal tau hyperphosphorylation. Here we show using Drosophila and mouse models of tauopathies that reductions in axonal transport can exacerbate human tau protein hyperphosphorylation, formation of insoluble aggregates and tau-dependent neurodegeneration. Together with previous work, our results suggest that non-lethal reductions in axonal transport, and perhaps other types of minor axonal stress, are sufficient to induce and/or accelerate abnormal tau behavior characteristic of Alzheimer's disease and other neurodegenerative tauopathies.
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Affiliation(s)
- Tomás L Falzone
- Department of Cellular and Molecular Medicine, Howard Hughes Medical Institute, University of California-San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
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46
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Taylor PL, Barker RA, Blume KG, Cattaneo E, Colman A, Deng H, Edgar H, Fox IJ, Gerstle C, Goldstein LSB, High KA, Lyall A, Parkman R, Pitossi FJ, Prentice ED, Rooke HM, Sipp DA, Srivastava A, Stayn S, Steinberg GK, Wagers AJ, Weissman IL. Patients beware: commercialized stem cell treatments on the web. Cell Stem Cell 2010; 7:43-9. [PMID: 20621049 DOI: 10.1016/j.stem.2010.06.001] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A report by the International Society for Stem Cell Research (ISSCR)'s Task Force on Unproven Stem Cell Treatments outlines development of resources for patients, their families, and physicians seeking information on stem cell treatments.
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47
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Lian I, Kim J, Okazawa H, Zhao J, Zhao B, Yu J, Chinnaiyan A, Israel MA, Goldstein LSB, Abujarour R, Ding S, Guan KL. The role of YAP transcription coactivator in regulating stem cell self-renewal and differentiation. Genes Dev 2010; 24:1106-18. [PMID: 20516196 DOI: 10.1101/gad.1903310] [Citation(s) in RCA: 569] [Impact Index Per Article: 40.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Yes-associated protein (YAP) is a potent transcription coactivator acting via binding to the TEAD transcription factor, and plays a critical role in organ size regulation. YAP is phosphorylated and inhibited by the Lats kinase, a key component of the Hippo tumor suppressor pathway. Elevated YAP protein levels and gene amplification have been implicated in human cancer. In this study, we report that YAP is inactivated during embryonic stem (ES) cell differentiation, as indicated by decreased protein levels and increased phosphorylation. Consistently, YAP is elevated during induced pluripotent stem (iPS) cell reprogramming. YAP knockdown leads to a loss of ES cell pluripotency, while ectopic expression of YAP prevents ES cell differentiation in vitro and maintains stem cell phenotypes even under differentiation conditions. Moreover, YAP binds directly to promoters of a large number of genes known to be important for stem cells and stimulates their expression. Our observations establish a critical role of YAP in maintaining stem cell pluripotency.
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Affiliation(s)
- Ian Lian
- Moores Cancer Center, University of California at San Diego, La Jolla, California 92093, USA
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48
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Abe N, Almenar-Queralt A, Lillo C, Shen Z, Lozach J, Briggs SP, Williams DS, Goldstein LSB, Cavalli V. Sunday driver interacts with two distinct classes of axonal organelles. J Biol Chem 2009; 284:34628-39. [PMID: 19801628 PMCID: PMC2787325 DOI: 10.1074/jbc.m109.035022] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2009] [Revised: 09/25/2009] [Indexed: 11/06/2022] Open
Abstract
The extreme polarized morphology of neurons poses a challenging problem for intracellular trafficking pathways. The distant synaptic terminals must communicate via axonal transport with the cell soma for neuronal survival, function, and repair. Multiple classes of organelles transported along axons may establish and maintain the polarized morphology of neurons, as well as control signaling and neuronal responses to extracellular cues such as neurotrophic or stress factors. We reported previously that the motor-binding protein Sunday Driver (syd), also known as JIP3 or JSAP1, links vesicular axonal transport to injury signaling. To better understand syd function in axonal transport and in the response of neurons to injury, we developed a purification strategy based on anti-syd antibodies conjugated to magnetic beads to identify syd-associated axonal vesicles. Electron microscopy analyses revealed two classes of syd-associated vesicles of distinct morphology. To identify the molecular anatomy of syd vesicles, we determined their protein composition by mass spectrometry. Gene Ontology analyses of each vesicle protein content revealed their unique identity and indicated that one class of syd vesicles belongs to the endocytic pathway, whereas another may belong to an anterogradely transported vesicle pool. To validate these findings, we examined the transport and localization of components of syd vesicles within axons of mouse sciatic nerve. Together, our results lead us to propose that endocytic syd vesicles function in part to carry injury signals back to the cell body, whereas anterograde syd vesicles may play a role in axonal outgrowth and guidance.
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Affiliation(s)
- Namiko Abe
- From the Department of Anatomy and Neurobiology, Washington University in St. Louis, St. Louis, Missouri 63110
| | | | | | - Zhouxin Shen
- the Section of Cell and Developmental Biology, Division of Biological Sciences, University of California, San Diego, La Jolla, California 92093, and
| | - Jean Lozach
- the Department of Cellular and Molecular Medicine, Howard Hughes Medical Institute
| | - Steven P. Briggs
- the Section of Cell and Developmental Biology, Division of Biological Sciences, University of California, San Diego, La Jolla, California 92093, and
| | - David S. Williams
- the Departments of Pharmacology and Neurosciences, and
- the Departments of Ophthalmology and Neurosciences, Jules Stein Eye Institute, UCLA, Los Angeles, California 90095
| | | | - Valeria Cavalli
- From the Department of Anatomy and Neurobiology, Washington University in St. Louis, St. Louis, Missouri 63110
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49
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Shah SB, Nolan R, Davis E, Stokin GB, Niesman I, Canto I, Glabe C, Goldstein LSB. Examination of potential mechanisms of amyloid-induced defects in neuronal transport. Neurobiol Dis 2009; 36:11-25. [PMID: 19497367 DOI: 10.1016/j.nbd.2009.05.016] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2009] [Revised: 05/03/2009] [Accepted: 05/25/2009] [Indexed: 01/31/2023] Open
Abstract
Microtubule-based neuronal transport pathways are impaired during the progression of Alzheimer's disease and other neurodegenerative conditions. However, mechanisms leading to defects in transport remain to be determined. We quantified morphological changes in neuronal cells following treatment with fibrils and unaggregated peptides of beta-amyloid (Abeta). Abeta fibrils induce axonal and dendritic swellings indicative of impaired transport. In contrast, Abeta peptides induce a necrotic phenotype in both neurons and non-neuronal cells. We tested several popular hypotheses by which aggregated Abeta could disrupt transport. Using fluorescent polystyrene beads, we developed experimental models of physical blockage and localized release of reactive oxygen species (ROS) that reliably induce swellings. Like the beads, Abeta fibrils localize in close proximity to swellings; however, fibril internalization is not required for disrupting transport. ROS and membrane permeability are also unlikely to be responsible for fibril-mediated toxicity. Collectively, our results indicate that multiple initiating factors converge upon pathways of defective transport.
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Affiliation(s)
- Sameer B Shah
- Fischell Department of Bioengineering, University of Maryland, College Park, MD, USA
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50
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Stokin GB, Almenar-Queralt A, Gunawardena S, Rodrigues EM, Falzone T, Kim J, Lillo C, Mount SL, Roberts EA, McGowan E, Williams DS, Goldstein LSB. Amyloid precursor protein-induced axonopathies are independent of amyloid-beta peptides. Hum Mol Genet 2008; 17:3474-86. [PMID: 18694898 DOI: 10.1093/hmg/ddn240] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Overexpression of amyloid precursor protein (APP), as well as mutations in the APP and presenilin genes, causes rare forms of Alzheimer's disease (AD). These genetic changes have been proposed to cause AD by elevating levels of amyloid-beta peptides (Abeta), which are thought to be neurotoxic. Since overexpression of APP also causes defects in axonal transport, we tested whether defects in axonal transport were the result of Abeta poisoning of the axonal transport machinery. Because directly varying APP levels also alters APP domains in addition to Abeta, we perturbed Abeta generation selectively by combining APP transgenes in Drosophila and mice with presenilin-1 (PS1) transgenes harboring mutations that cause familial AD (FAD). We found that combining FAD mutant PS1 with FAD mutant APP increased Abeta42/Abeta40 ratios and enhanced amyloid deposition as previously reported. Surprisingly, however, this combination suppressed rather than increased APP-induced axonal transport defects in both Drosophila and mice. In addition, neuronal apoptosis induced by expression of FAD mutant human APP in Drosophila was suppressed by co-expressing FAD mutant PS1. We also observed that directly elevating Abeta with fusions to the Familial British and Danish Dementia-related BRI protein did not enhance axonal transport phenotypes in APP transgenic mice. Finally, we observed that perturbing Abeta ratios in the mouse by combining FAD mutant PS1 with FAD mutant APP did not enhance APP-induced behavioral defects. A potential mechanism to explain these findings was suggested by direct analysis of axonal transport in the mouse, which revealed that axonal transport or entry of APP into axons is reduced by FAD mutant PS1. Thus, we suggest that APP-induced axonal defects are not caused by Abeta.
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Affiliation(s)
- Gorazd B Stokin
- Department of Cellular and Molecular Medicine, Howard Hughes Medical Institute, School of Medicine, University of California, San Diego, La Jolla, CA 92093-0683, USA
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