1
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Jin M, Iwamoto Y, Shirazinejad C, Drubin DG. Intersectin1 promotes clathrin-mediated endocytosis by organizing and stabilizing endocytic protein interaction networks. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.22.590579. [PMID: 38712149 PMCID: PMC11071352 DOI: 10.1101/2024.04.22.590579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
During clathrin-mediated endocytosis (CME), dozens of proteins are recruited to nascent CME sites on the plasma membrane. Coordination of endocytic protein recruitment in time and space is important for efficient CME. Here, we show that the multivalent scaffold protein intersectin1 (ITSN1) promotes CME by organizing and stabilizing endocytic protein interaction networks. By live-cell imaging of genome-edited cells, we observed that endogenously labeled ITSN1 is recruited to CME sites shortly after they begin to assemble. Knocking down ITSN1 impaired endocytic protein recruitment during the stabilization stage of CME site assembly. Artificially locating ITSN1 to the mitochondria surface was sufficient to assemble puncta consisting of CME initiation proteins, including EPS15, FCHO, adaptor proteins, the AP2 complex and epsin1 (EPN1), and the vesicle scission GTPase dynamin2 (DNM2). ITSN1 can form puncta and recruit DNM2 independently of EPS15/FCHO or EPN1. Our work redefines ITSN1's primary endocytic role as organizing and stabilizing the CME protein interaction networks rather than a previously suggested role in initiation and provides new insights into the multi-step and multi-zone organization of CME site assembly.
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Affiliation(s)
- Meiyan Jin
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
- Current Address: Department of Biology, University of Florida, Gainesville, Fl 32611, USA
| | - Yuichiro Iwamoto
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
| | - Cyna Shirazinejad
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
| | - David G. Drubin
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720, USA
- Lead author
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2
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Zhang T, Hale AT, Guo S, York JD. Coordinated inositide lipid-phosphatase activities of synaptojanin modulates actin cytoskeleton organization. Adv Biol Regul 2024; 91:101012. [PMID: 38220563 DOI: 10.1016/j.jbior.2023.101012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 12/27/2023] [Indexed: 01/16/2024]
Abstract
Synaptojanin proteins are evolutionarily conserved regulators of vesicle transport and membrane homeostasis. Disruption of synaptojanin function has been implicated in a wide range of neurological disorders. Synaptojanins act as dual-functional lipid phosphatases capable of hydrolyzing a variety of phosphoinositides (PIPs) through autonomous SAC1-like PIP 4-phosphatase and PIP2 5-phosphatase domains. The rarity of an evolutionary configuration of tethering two distinct enzyme activities in a single protein prompted us to investigate their individual and combined roles in budding yeast. Both PIP and PIP2 phosphatase activities are encoded by multiple gene products and are independently essential for cell viability. In contrast, we observed that the synaptojanin proteins utilized both lipid-phosphatase activities to properly coordinate polarized distribution of actin during the cell cycle. Expression of each activity untethered (in trans) failed to properly reconstitute the basal actin regulatory activity; whereas tethering (in cis), even through synthetic linkers, was sufficient to complement these defects. Studies of chimeric proteins harboring PIP and PIP2 phosphatase domains from a variety of gene products indicate synaptojanin proteins have highly specialized activities and that the length of the linker between the lipid-phosphatase domains is critical for actin regulatory activity. Our data are consistent with synaptojanin possessing a strict requirement for both two-domain configuration for some but not all functions and provide mechanistic insights into a coordinated role of tethering distinct lipid-phosphatase activities.
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Affiliation(s)
- Tong Zhang
- Departments of Pharmacology and Cancer Biology, Howard Hughes Medical Institute, Duke University Medical Center, Durham, NC, 27710, USA
| | - Andrew T Hale
- Department of Biochemistry, Vanderbilt University, Nashville, TN, 37232, USA
| | - Shuling Guo
- Departments of Pharmacology and Cancer Biology, Howard Hughes Medical Institute, Duke University Medical Center, Durham, NC, 27710, USA
| | - John D York
- Departments of Pharmacology and Cancer Biology, Howard Hughes Medical Institute, Duke University Medical Center, Durham, NC, 27710, USA; Department of Biochemistry, Vanderbilt University, Nashville, TN, 37232, USA.
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3
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Song SH, Augustine GJ. Different mechanisms of synapsin-induced vesicle clustering at inhibitory and excitatory synapses. Cell Rep 2023; 42:113004. [PMID: 37597184 DOI: 10.1016/j.celrep.2023.113004] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 06/26/2023] [Accepted: 08/02/2023] [Indexed: 08/21/2023] Open
Abstract
Synapsins cluster synaptic vesicles (SVs) to provide a reserve pool (RP) of SVs that maintains synaptic transmission during sustained activity. However, it is unclear how synapsins cluster SVs. Here we show that either liquid-liquid phase separation (LLPS) or tetramerization-dependent cross-linking can cluster SVs, depending on whether a synapse is excitatory or inhibitory. Cell-free reconstitution reveals that both mechanisms can cluster SVs, with tetramerization being more effective. At inhibitory synapses, perturbing synapsin-dependent LLPS impairs SV clustering and synchronization of gamma-aminobutyric acid (GABA) release, while preventing synapsin tetramerization does not. At glutamatergic synapses, the opposite is true: synapsin tetramerization enhances clustering of glutamatergic SVs and mobilization of these SVs from the RP, while synapsin LLPS does not. Comparison of inhibitory and excitatory transmission during prolonged synaptic activity reveals that synapsin LLPS serves as a brake to limit GABA release, while synapsin tetramerization enables rapid mobilization of SVs from the RP to sustain glutamate release.
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Affiliation(s)
- Sang-Ho Song
- Neuroscience and Mental Health Program, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 308232, Singapore
| | - George J Augustine
- Neuroscience and Mental Health Program, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 308232, Singapore.
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4
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Yu Y, Yoshimura SH. Self-assembly of CIP4 drives actin-mediated asymmetric pit-closing in clathrin-mediated endocytosis. Nat Commun 2023; 14:4602. [PMID: 37528083 PMCID: PMC10393992 DOI: 10.1038/s41467-023-40390-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Accepted: 07/23/2023] [Indexed: 08/03/2023] Open
Abstract
Clathrin-mediated endocytosis is pivotal to signal transduction pathways between the extracellular environment and the intracellular space. Evidence from live-cell imaging and super-resolution microscopy of mammalian cells suggests an asymmetric distribution of actin fibres near the clathrin-coated pit, which induces asymmetric pit-closing rather than radial constriction. However, detailed molecular mechanisms of this 'asymmetricity' remain elusive. Herein, we used high-speed atomic force microscopy to demonstrate that CIP4, a multi-domain protein with a classic F-BAR domain and intrinsically disordered regions, is necessary for asymmetric pit-closing. Strong self-assembly of CIP4 via intrinsically disordered regions, together with stereospecific interactions with the curved membrane and actin-regulating proteins, generates a small actin-rich environment near the pit, which deforms the membrane and closes the pit. Our results provide mechanistic insights into how disordered and structured domain collaboration promotes spatio-temporal actin polymerisation near the plasma membrane.
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Affiliation(s)
- Yiming Yu
- Graduate School of Biostudies, Kyoto University, Kyoto, 606-8501, Japan
| | - Shige H Yoshimura
- Graduate School of Biostudies, Kyoto University, Kyoto, 606-8501, Japan.
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5
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Zhou X, Feliciano P, Shu C, Wang T, Astrovskaya I, Hall JB, Obiajulu JU, Wright JR, Murali SC, Xu SX, Brueggeman L, Thomas TR, Marchenko O, Fleisch C, Barns SD, Snyder LG, Han B, Chang TS, Turner TN, Harvey WT, Nishida A, O'Roak BJ, Geschwind DH, Michaelson JJ, Volfovsky N, Eichler EE, Shen Y, Chung WK. Integrating de novo and inherited variants in 42,607 autism cases identifies mutations in new moderate-risk genes. Nat Genet 2022; 54:1305-1319. [PMID: 35982159 PMCID: PMC9470534 DOI: 10.1038/s41588-022-01148-2] [Citation(s) in RCA: 130] [Impact Index Per Article: 65.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Accepted: 06/28/2022] [Indexed: 12/16/2022]
Abstract
To capture the full spectrum of genetic risk for autism, we performed a two-stage analysis of rare de novo and inherited coding variants in 42,607 autism cases, including 35,130 new cases recruited online by SPARK. We identified 60 genes with exome-wide significance (P < 2.5 × 10-6), including five new risk genes (NAV3, ITSN1, MARK2, SCAF1 and HNRNPUL2). The association of NAV3 with autism risk is primarily driven by rare inherited loss-of-function (LoF) variants, with an estimated relative risk of 4, consistent with moderate effect. Autistic individuals with LoF variants in the four moderate-risk genes (NAV3, ITSN1, SCAF1 and HNRNPUL2; n = 95) have less cognitive impairment than 129 autistic individuals with LoF variants in highly penetrant genes (CHD8, SCN2A, ADNP, FOXP1 and SHANK3) (59% vs 88%, P = 1.9 × 10-6). Power calculations suggest that much larger numbers of autism cases are needed to identify additional moderate-risk genes.
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Affiliation(s)
- Xueya Zhou
- Department of Pediatrics, Columbia University Medical Center, New York, NY, USA.,Department of Systems Biology, Columbia University Medical Center, New York, NY, USA
| | | | - Chang Shu
- Department of Pediatrics, Columbia University Medical Center, New York, NY, USA.,Department of Systems Biology, Columbia University Medical Center, New York, NY, USA
| | - Tianyun Wang
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA.,Department of Medical Genetics, Center for Medical Genetics, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China.,Neuroscience Research Institute, Department of Neurobiology, School of Basic Medical Sciences, Peking University Health Science Center; Key Laboratory for Neuroscience, Ministry of Education of China & National Health Commission of China, Beijing, China
| | | | | | - Joseph U Obiajulu
- Department of Pediatrics, Columbia University Medical Center, New York, NY, USA.,Department of Systems Biology, Columbia University Medical Center, New York, NY, USA
| | | | - Shwetha C Murali
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA.,Howard Hughes Medical Institute, University of Washington, Seattle, WA, USA
| | | | - Leo Brueggeman
- Department of Psychiatry, University of Iowa Carver College of Medicine, Iowa City, IA, USA
| | - Taylor R Thomas
- Department of Psychiatry, University of Iowa Carver College of Medicine, Iowa City, IA, USA
| | | | | | | | | | - Bing Han
- Simons Foundation, New York, NY, USA
| | - Timothy S Chang
- Program in Neurogenetics, Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | - Tychele N Turner
- Department of Genetics, Washington University, St. Louis, MO, USA
| | - William T Harvey
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA
| | - Andrew Nishida
- Department of Molecular & Medical Genetics, Oregon Health & Science University, Portland, OR, USA
| | - Brian J O'Roak
- Department of Molecular & Medical Genetics, Oregon Health & Science University, Portland, OR, USA
| | - Daniel H Geschwind
- Program in Neurogenetics, Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, USA
| | | | - Jacob J Michaelson
- Department of Psychiatry, University of Iowa Carver College of Medicine, Iowa City, IA, USA
| | | | - Evan E Eichler
- Department of Genome Sciences, University of Washington School of Medicine, Seattle, WA, USA.,Howard Hughes Medical Institute, University of Washington, Seattle, WA, USA
| | - Yufeng Shen
- Department of Systems Biology, Columbia University Medical Center, New York, NY, USA.,Department of Biomedical Informatics, Columbia University Medical Center, New York, NY, USA
| | - Wendy K Chung
- Department of Pediatrics, Columbia University Medical Center, New York, NY, USA. .,Simons Foundation, New York, NY, USA. .,Department of Medicine, Columbia University Medical Center, New York, NY, USA.
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6
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Hwang R, Dang LH, Chen J, Lee JH, Marquer C. Triplication of Synaptojanin 1 in Alzheimer's Disease Pathology in Down Syndrome. Curr Alzheimer Res 2022; 19:795-807. [PMID: 36464875 DOI: 10.2174/1567205020666221202102832] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Revised: 10/29/2022] [Accepted: 11/02/2022] [Indexed: 12/12/2022]
Abstract
Down Syndrome (DS), caused by triplication of human chromosome 21 (Hsa21) is the most common form of intellectual disability worldwide. Recent progress in healthcare has resulted in a dramatic increase in the lifespan of individuals with DS. Unfortunately, most will develop Alzheimer's disease like dementia (DS-AD) as they age. Understanding similarities and differences between DSAD and the other forms of the disease - i.e., late-onset AD (LOAD) and autosomal dominant AD (ADAD) - will provide important clues for the treatment of DS-AD. In addition to the APP gene that codes the precursor of the main component of amyloid plaques found in the brain of AD patients, other genes on Hsa21 are likely to contribute to disease initiation and progression. This review focuses on SYNJ1, coding the phosphoinositide phosphatase synaptojanin 1 (SYNJ1). First, we highlight the function of SYNJ1 in the brain. We then summarize the involvement of SYNJ1 in the different forms of AD at the genetic, transcriptomic, proteomic and neuropathology levels in humans. We further examine whether results in humans correlate with what has been described in murine and cellular models of the disease and report possible mechanistic links between SYNJ1 and the progression of the disease. Finally, we propose a set of questions that would further strengthen and clarify the role of SYNJ1 in the different forms of AD.
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Grants
- U19 AG068054, U01 AG051412, UL1TR001873, R01 AG058918, R01 AG058918 S1, P30AG10161, P30AG72975, R01AG15819, R01AG17917, R01AG03-6836, U01AG46152, U01AG61356, U01AG046139, P50 AG016574, R01 AG032990, U01AG046139, R01AG01-8023, U01AG006576, U01AG006786, R01AG025711, R01AG017216, R01AG003949, R01NS080820, U24NS07-2026, P30AG19610, U01AG046170, RF1AG057440, U24AG061340 NIH/NIA , National Institutes of Health
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Affiliation(s)
- Robert Hwang
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Irving Medical Center, New York City, NY, 10032, USA
| | - Lam-Ha Dang
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Irving Medical Center, New York City, NY, 10032, USA
- G.H. Sergievsky Center, Columbia University Medical Center, New York, NY 10032, USA
- Departments of Epidemiology and Neurology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Jacinda Chen
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Irving Medical Center, New York City, NY, 10032, USA
| | - Joseph H Lee
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Irving Medical Center, New York City, NY, 10032, USA
- G.H. Sergievsky Center, Columbia University Medical Center, New York, NY 10032, USA
- Departments of Epidemiology and Neurology, Columbia University Medical Center, New York, NY, 10032, USA
| | - Catherine Marquer
- Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Irving Medical Center, New York City, NY, 10032, USA
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York City, NY, 10032, USA
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7
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Kovermann M, Weininger U, Löw C. Completing the family of human EH domains: Solution structure of the internal EH domain of γ-synergin. Protein Sci 2021; 31:811-821. [PMID: 34967068 PMCID: PMC8927860 DOI: 10.1002/pro.4269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Revised: 12/11/2021] [Accepted: 12/24/2021] [Indexed: 11/05/2022]
Abstract
Eps15 homology (EH) domains are universal interaction domains to establish networks of protein-protein interactions in the cell. These networks mainly coordinate cellular functions including endocytosis, actin remodeling and other intracellular signaling pathways. They are well characterized in structural terms, except for the internal EH domain from human γ-synergin (EHγ). Here, we complete the family of EH domain structures by determining the solution structure of the EHγ domain. The structural ensemble follows the canonical EH domain fold and the identified binding site is similar to other known EH domains. But EHγ differs significantly in the N- and C-terminal regions. The N-terminal α-helix is shortened compared to known homologs, while the C-terminal one is fully formed. A significant proportion of the remaining N- and C-terminal regions are well structured, a feature not seen in other EH domains. Single mutations in both the N-terminal and the C-terminal structured extensions lead to the loss of the distinct three-dimensional fold and turn EHγ into a molten globule like state. Therefore, we propose that the structural extensions in EHγ function as a clamp and are undoubtedly required to maintain its tertiary fold. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Michael Kovermann
- Department of Chemistry, University of Konstanz, Universitätsstrasse 10, 78457, Konstanz, Germany.,Konstanz Research School Chemical Biology KoRS-CB, University of Konstanz, Universitätsstrasse 10, 78457, Konstanz, Germany
| | - Ulrich Weininger
- Institute of Physics, Biophysics, Martin-Luther-University Halle-Wittenberg, D-06120 Halle (Saale), Germany
| | - Christian Löw
- Centre for Structural Systems Biology (CSSB), Notkestrasse 85, D-22607 Hamburg, Germany Molecular Biology Laboratory (EMBL), Hamburg Unit c/o Deutsches Elektronen Synchrotron (DESY), Notkestrasse 85, D-22607, Hamburg, Germany
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8
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Chen H, Wang T, Huang S, Zeng P. New novel non-MHC genes were identified for cervical cancer with an integrative analysis approach of transcriptome-wide association study. J Cancer 2021; 12:840-848. [PMID: 33403041 PMCID: PMC7778537 DOI: 10.7150/jca.47918] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 10/18/2020] [Indexed: 12/28/2022] Open
Abstract
Although genome-wide association studies (GWAS) have successfully identified multiple genetic variants associated with cervical cancer, the functional role of those variants is not well understood. To bridge such gap, we integrated the largest cervical cancer GWAS (N = 9,347) with gene expression measured in six human tissues to perform a multi-tissue transcriptome-wide association study (TWAS). We identified a total of 20 associated genes in the European population, especially four novel non-MHC genes (i.e. WDR19, RP11-384K6.2, RP11-384K6.6 and ITSN1). Further, we attempted to validate our results in another independent cervical cancer GWAS from the East Asian population (N = 3,314) and re-discovered four genes including WDR19, HLA-DOB, MICB and OR2B8P. In our subsequent co-expression analysis, we discovered SLAMF7 and LTA were co-expressed in TCGA tumor samples and showed both WDR19 and ITSN1 were enriched in "plasma membrane". Using the protein-protein interaction analysis we observed strong interactions between the proteins produced by genes that are associated with cervical cancer. Overall, our study identified multiple candidate genes, especially four non-MHC genes, which may be causally associated with the risk of cervical cancer. However, further investigations with larger sample size are warranted to validate our findings in diverse populations.
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Affiliation(s)
- Haimiao Chen
- Department of Epidemiology and Biostatistics, School of Public Health, Xuzhou Medical University, Xuzhou, Jiangsu, 221004, China
| | - Ting Wang
- Department of Epidemiology and Biostatistics, School of Public Health, Xuzhou Medical University, Xuzhou, Jiangsu, 221004, China
| | - Shuiping Huang
- Department of Epidemiology and Biostatistics, School of Public Health, Xuzhou Medical University, Xuzhou, Jiangsu, 221004, China
- Center for Medical Statistics and Data Analysis, School of Public Health, Xuzhou Medical University, Xuzhou, Jiangsu, 221004, China
| | - Ping Zeng
- Department of Epidemiology and Biostatistics, School of Public Health, Xuzhou Medical University, Xuzhou, Jiangsu, 221004, China
- Center for Medical Statistics and Data Analysis, School of Public Health, Xuzhou Medical University, Xuzhou, Jiangsu, 221004, China
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9
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Overhoff M, De Bruyckere E, Kononenko NL. Mechanisms of neuronal survival safeguarded by endocytosis and autophagy. J Neurochem 2020; 157:263-296. [PMID: 32964462 DOI: 10.1111/jnc.15194] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 08/21/2020] [Accepted: 09/08/2020] [Indexed: 12/11/2022]
Abstract
Multiple aspects of neuronal physiology crucially depend on two cellular pathways, autophagy and endocytosis. During endocytosis, extracellular components either unbound or recognized by membrane-localized receptors (termed "cargo") become internalized into plasma membrane-derived vesicles. These can serve to either recycle the material back to the plasma membrane or send it for degradation to lysosomes. Autophagy also uses lysosomes as a terminal degradation point, although instead of degrading the plasma membrane-derived cargo, autophagy eliminates detrimental cytosolic material and intracellular organelles, which are transported to lysosomes by means of double-membrane vesicles, referred to as autophagosomes. Neurons, like all non-neuronal cells, capitalize on autophagy and endocytosis to communicate with the environment and maintain protein and organelle homeostasis. Additionally, the highly polarized, post-mitotic nature of neurons made them adopt these two pathways for cell-specific functions. These include the maintenance of the synaptic vesicle pool in the pre-synaptic terminal and the long-distance transport of signaling molecules. Originally discovered independently from each other, it is now clear that autophagy and endocytosis are closely interconnected and share several common participating molecules. Considering the crucial role of autophagy and endocytosis in cell type-specific functions in neurons, it is not surprising that defects in both pathways have been linked to the pathology of numerous neurodegenerative diseases. In this review, we highlight the recent knowledge of the role of endocytosis and autophagy in neurons with a special focus on synaptic physiology and discuss how impairments in genes coding for autophagy and endocytosis proteins can cause neurodegeneration.
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Affiliation(s)
- Melina Overhoff
- CECAD Cluster of Excellence, Institute for Genetics, University of Cologne, Cologne, Germany
| | - Elodie De Bruyckere
- CECAD Cluster of Excellence, Institute for Genetics, University of Cologne, Cologne, Germany
| | - Natalia L Kononenko
- CECAD Cluster of Excellence, Institute for Genetics, University of Cologne, Cologne, Germany
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10
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Gubar O, Croisé P, Kropyvko S, Gryaznova T, Tóth P, Blangy A, Vitale N, Rynditch A, Gasman S, Ory S. The atypical Rho GTPase RhoU interacts with intersectin-2 to regulate endosomal recycling pathways. J Cell Sci 2020; 133:jcs234104. [PMID: 32737221 DOI: 10.1242/jcs.234104] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 07/21/2020] [Indexed: 01/22/2023] Open
Abstract
Rho GTPases play a key role in various membrane trafficking processes. RhoU is an atypical small Rho GTPase related to Rac/Cdc42, which possesses unique N- and C-terminal domains that regulate its function and its subcellular localization. RhoU localizes at the plasma membrane, on endosomes and in cell adhesion structures where it governs cell signaling, differentiation and migration. However, despite its endomembrane localization, RhoU function in vesicular trafficking has been unexplored. Here, we identified intersectins (ITSNs) as new binding partners for RhoU and showed that the second PxxP motif at the N terminus of RhoU mediated interactions with the SH3 domains of ITSNs. To evaluate the function of RhoU and ITSNs in vesicular trafficking, we used fluorescent transferrin as a cargo for uptake experiments. We showed that silencing of either RhoU or ITSN2, but not ITSN1, increased transferrin accumulation in early endosomes, resulting from a defect in fast vesicle recycling. Concomitantly, RhoU and ITSN2 colocalized to a subset of Rab4-positive vesicles, suggesting that a RhoU-ITSN2 interaction may occur on fast recycling endosomes to regulate the fate of vesicular cargos.
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Affiliation(s)
- Olga Gubar
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000 Strasbourg, France
- Institute of Molecular Biology and Genetics NASU, 150 Zabolotnogo Street, Kyiv 03680, Ukraine
| | - Pauline Croisé
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000 Strasbourg, France
| | - Sergii Kropyvko
- Institute of Molecular Biology and Genetics NASU, 150 Zabolotnogo Street, Kyiv 03680, Ukraine
| | - Tetyana Gryaznova
- Institute of Molecular Biology and Genetics NASU, 150 Zabolotnogo Street, Kyiv 03680, Ukraine
| | - Petra Tóth
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000 Strasbourg, France
| | - Anne Blangy
- Centre de Recherche en Biologie Cellulaire de Montpellier (CRBM), Univ. Montpellier, CNRS, 34000 Montpellier, France
| | - Nicolas Vitale
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000 Strasbourg, France
| | - Alla Rynditch
- Institute of Molecular Biology and Genetics NASU, 150 Zabolotnogo Street, Kyiv 03680, Ukraine
| | - Stéphane Gasman
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000 Strasbourg, France
| | - Stéphane Ory
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives, F-67000 Strasbourg, France
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11
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Pankivskyi S, Pastré D, Steiner E, Joshi V, Rynditch A, Hamon L. ITSN1 regulates SAM68 solubility through SH3 domain interactions with SAM68 proline-rich motifs. Cell Mol Life Sci 2020; 78:1745-1763. [PMID: 32780150 PMCID: PMC7904728 DOI: 10.1007/s00018-020-03610-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 06/03/2020] [Accepted: 07/22/2020] [Indexed: 02/06/2023]
Abstract
SAM68 is an mRNA-binding protein involved in mRNA processing in the nucleus that forms membraneless compartments called SAM68 Nuclear Bodies (SNBs). We found that intersectin 1 (ITSN1), a multidomain scaffold protein harboring five soluble SH3 domains, interacts with SAM68 proline-rich motifs (PRMs) surrounded by self-adhesive low complexity domains. While SAM68 is poorly soluble in vitro, the interaction of ITSN1 SH3 domains and mRNA with SAM68 enhances its solubility. In HeLa cells, the interaction between the first ITSN1 SH3 domain (SH3A) and P0, the N-terminal PRM of SAM68, induces the dissociation of SNBs. In addition, we reveal the ability of another SH3 domain (SH3D) of ITSN1 to bind to mRNAs. ITSN1 and mRNA may thus act in concert to promote SAM68 solubilization, consistent with the absence of mRNA in SNBs in cells. Together, these results support the notion of a specific chaperoning of PRM-rich SAM68 within nuclear ribonucleoprotein complexes by ITSN1 that may regulate the processing of a fraction of nuclear mRNAs, notably SAM68-controlled splicing events related to higher neuronal functions or cancer progression. This observation may also serve as a putative model of the interaction between other PRM-rich RBPs and signaling proteins harboring SH3 domains.
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Affiliation(s)
- S Pankivskyi
- SABNP, Univ Evry, INSERM U1204, Université Paris-Saclay, 91025, Evry, France.,Institute of Molecular Biology and Genetics, The National Academy of Sciences, 150 Zabolotnogo Street, Kyiv, 03680, Ukraine
| | - D Pastré
- SABNP, Univ Evry, INSERM U1204, Université Paris-Saclay, 91025, Evry, France
| | - E Steiner
- SABNP, Univ Evry, INSERM U1204, Université Paris-Saclay, 91025, Evry, France
| | - V Joshi
- SABNP, Univ Evry, INSERM U1204, Université Paris-Saclay, 91025, Evry, France
| | - A Rynditch
- Institute of Molecular Biology and Genetics, The National Academy of Sciences, 150 Zabolotnogo Street, Kyiv, 03680, Ukraine.
| | - L Hamon
- SABNP, Univ Evry, INSERM U1204, Université Paris-Saclay, 91025, Evry, France.
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12
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Gowrisankaran S, Houy S, Del Castillo JGP, Steubler V, Gelker M, Kroll J, Pinheiro PS, Schwitters D, Halbsgut N, Pechstein A, van Weering JRT, Maritzen T, Haucke V, Raimundo N, Sørensen JB, Milosevic I. Endophilin-A coordinates priming and fusion of neurosecretory vesicles via intersectin. Nat Commun 2020; 11:1266. [PMID: 32152276 PMCID: PMC7062783 DOI: 10.1038/s41467-020-14993-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 02/12/2020] [Indexed: 12/17/2022] Open
Abstract
Endophilins-A are conserved endocytic adaptors with membrane curvature-sensing and -inducing properties. We show here that, independently of their role in endocytosis, endophilin-A1 and endophilin-A2 regulate exocytosis of neurosecretory vesicles. The number and distribution of neurosecretory vesicles were not changed in chromaffin cells lacking endophilin-A, yet fast capacitance and amperometry measurements revealed reduced exocytosis, smaller vesicle pools and altered fusion kinetics. The levels and distributions of the main exocytic and endocytic factors were unchanged, and slow compensatory endocytosis was not robustly affected. Endophilin-A’s role in exocytosis is mediated through its SH3-domain, specifically via a direct interaction with intersectin-1, a coordinator of exocytic and endocytic traffic. Endophilin-A not able to bind intersectin-1, and intersectin-1 not able to bind endophilin-A, resulted in similar exocytic defects in chromaffin cells. Altogether, we report that two endocytic proteins, endophilin-A and intersectin-1, are enriched on neurosecretory vesicles and regulate exocytosis by coordinating neurosecretory vesicle priming and fusion. Endophilins-A are conserved membrane-associated proteins required for endocytosis. Here, the authors report that endophilins-A also promote exocytosis of neurosecretory vesicles by coordinating priming and fusion through intersectin-1, independently of their roles in different types of endocytosis.
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Affiliation(s)
- Sindhuja Gowrisankaran
- European Neuroscience Institute-A Joint Initiative of the University Medical Center Göttingen and the Max Planck Society Göttingen, Göttingen, Germany
| | - Sébastien Houy
- University of Copenhagen, Department for Neuroscience, Faculty of Health and Medical Sciences, Copenhagen, Denmark
| | - Johanna G Peña Del Castillo
- European Neuroscience Institute-A Joint Initiative of the University Medical Center Göttingen and the Max Planck Society Göttingen, Göttingen, Germany
| | - Vicky Steubler
- European Neuroscience Institute-A Joint Initiative of the University Medical Center Göttingen and the Max Planck Society Göttingen, Göttingen, Germany
| | - Monika Gelker
- European Neuroscience Institute-A Joint Initiative of the University Medical Center Göttingen and the Max Planck Society Göttingen, Göttingen, Germany
| | - Jana Kroll
- European Neuroscience Institute-A Joint Initiative of the University Medical Center Göttingen and the Max Planck Society Göttingen, Göttingen, Germany
| | - Paulo S Pinheiro
- University of Copenhagen, Department for Neuroscience, Faculty of Health and Medical Sciences, Copenhagen, Denmark.,Center for Neuroscience and Cell Biology, University of Coimbra, Coimbra, Portugal
| | - Dirk Schwitters
- European Neuroscience Institute-A Joint Initiative of the University Medical Center Göttingen and the Max Planck Society Göttingen, Göttingen, Germany
| | - Nils Halbsgut
- European Neuroscience Institute-A Joint Initiative of the University Medical Center Göttingen and the Max Planck Society Göttingen, Göttingen, Germany
| | - Arndt Pechstein
- Leibniz Research Institute for Molecular Pharmacology, Molecular Physiology and Cell Biology Section, Berlin, Germany
| | - Jan R T van Weering
- Department of Clinical Genetics, Center for Neurogenomics and Cognitive Research, Amsterdam UMC, Amsterdam, The Netherlands
| | - Tanja Maritzen
- Leibniz Research Institute for Molecular Pharmacology, Molecular Physiology and Cell Biology Section, Berlin, Germany
| | - Volker Haucke
- Leibniz Research Institute for Molecular Pharmacology, Molecular Physiology and Cell Biology Section, Berlin, Germany
| | - Nuno Raimundo
- Institute for Cellular Biochemistry, University Medical Center Göttingen (UMG), Göttingen, Germany
| | - Jakob B Sørensen
- University of Copenhagen, Department for Neuroscience, Faculty of Health and Medical Sciences, Copenhagen, Denmark.
| | - Ira Milosevic
- European Neuroscience Institute-A Joint Initiative of the University Medical Center Göttingen and the Max Planck Society Göttingen, Göttingen, Germany.
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13
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Girouard MP, Simas T, Hua L, Morquette B, Khazaei MR, Unsain N, Johnstone AD, Rambaldi I, Sanz RL, Di Raddo ME, Gamage KK, Yong Y, Willis DE, Verge VMK, Barker PA, Deppmann C, Fournier AE. Collapsin Response Mediator Protein 4 (CRMP4) Facilitates Wallerian Degeneration and Axon Regeneration following Sciatic Nerve Injury. eNeuro 2020; 7:ENEURO.0479-19.2020. [PMID: 32001550 PMCID: PMC7053045 DOI: 10.1523/eneuro.0479-19.2020] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 01/14/2020] [Accepted: 01/15/2020] [Indexed: 11/29/2022] Open
Abstract
In contrast to neurons in the CNS, damaged neurons from the peripheral nervous system (PNS) regenerate, but this process can be slow and imperfect. Successful regeneration is orchestrated by cytoskeletal reorganization at the tip of the proximal axon segment and cytoskeletal disassembly of the distal segment. Collapsin response mediator protein 4 (CRMP4) is a cytosolic phospho-protein that regulates the actin and microtubule cytoskeleton. During development, CRMP4 promotes growth cone formation and dendrite development. Paradoxically, in the adult CNS, CRMP4 impedes axon regeneration. Here, we investigated the involvement of CRMP4 in peripheral nerve injury in male and female Crmp4-/- mice following sciatic nerve injury. We find that sensory axon regeneration and Wallerian degeneration are impaired in Crmp4-/- mice following sciatic nerve injury. In vitro analysis of dissociated dorsal root ganglion (DRG) neurons from Crmp4-/- mice revealed that CRMP4 functions in the proximal axon segment to promote the regrowth of severed DRG neurons and in the distal axon segment where it facilitates Wallerian degeneration through calpain-dependent formation of harmful CRMP4 fragments. These findings reveal an interesting dual role for CRMP4 in proximal and distal axon segments of injured sensory neurons that coordinately facilitate PNS axon regeneration.
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Affiliation(s)
- Marie-Pier Girouard
- Department of Neurology and Neurosurgery, Montréal Neurological Institute and Hospital, Montréal, Québec H3A 2B4, Canada
| | - Tristan Simas
- Department of Neurology and Neurosurgery, Montréal Neurological Institute and Hospital, Montréal, Québec H3A 2B4, Canada
| | - Luyang Hua
- Department of Neurology and Neurosurgery, Montréal Neurological Institute and Hospital, Montréal, Québec H3A 2B4, Canada
| | - Barbara Morquette
- Department of Neurology and Neurosurgery, Montréal Neurological Institute and Hospital, Montréal, Québec H3A 2B4, Canada
| | - Mohamad R Khazaei
- Department of Neurology and Neurosurgery, Montréal Neurological Institute and Hospital, Montréal, Québec H3A 2B4, Canada
| | - Nicolas Unsain
- Instituto de Investigación Médica Mercedes y Martín Ferreyra (INIMEC), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), 5016 Córdoba, Argentina
| | - Aaron D Johnstone
- Department of Neurology and Neurosurgery, Montréal Neurological Institute and Hospital, Montréal, Québec H3A 2B4, Canada
| | - Isabel Rambaldi
- Department of Neurology and Neurosurgery, Montréal Neurological Institute and Hospital, Montréal, Québec H3A 2B4, Canada
| | - Ricardo L Sanz
- Department of Neurology and Neurosurgery, Montréal Neurological Institute and Hospital, Montréal, Québec H3A 2B4, Canada
| | | | - Kanchana K Gamage
- Department of Biology, University of Virginia, Charlottesville, Virginia 22903
| | - Yu Yong
- Department of Biology, University of Virginia, Charlottesville, Virginia 22903
| | - Dianna E Willis
- Brain and Mind Research Institute, Weill Cornell Medicine, New York, New York 10065
- Burke Institute, Weill Cornell Medicine, White Plains, New York 10605
| | - Valerie M K Verge
- Department of Anatomy, Physiology and Pharmacology, University of Saskatchewan-CMSNRC, Saskatoon, Saskatchewan S7N 5E5, Canada
| | - Philip A Barker
- Department of Neurology and Neurosurgery, Montréal Neurological Institute and Hospital, Montréal, Québec H3A 2B4, Canada
- Department of Biology, University of British Columbia, Kelowna, British Columbia V1V 1V7, Canada
| | | | - Alyson E Fournier
- Department of Neurology and Neurosurgery, Montréal Neurological Institute and Hospital, Montréal, Québec H3A 2B4, Canada
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14
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Traub LM. A nanobody-based molecular toolkit provides new mechanistic insight into clathrin-coat initiation. eLife 2019; 8:41768. [PMID: 31038455 PMCID: PMC6524969 DOI: 10.7554/elife.41768] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 04/24/2019] [Indexed: 12/21/2022] Open
Abstract
Besides AP-2 and clathrin triskelia, clathrin coat inception depends on a group of early-arriving proteins including Fcho1/2 and Eps15/R. Using genome-edited cells, we described the role of the unstructured Fcho linker in stable AP-2 membrane deposition. Here, expanding this strategy in combination with a new set of llama nanobodies against EPS15 shows an FCHO1/2–EPS15/R partnership plays a decisive role in coat initiation. A nanobody containing an Asn-Pro-Phe peptide within the complementarity-determining region 3 loop is a function-blocking pseudoligand for tandem EPS15/R EH domains. Yet, in living cells, EH domains gathered at clathrin-coated structures are poorly accessible, indicating residence by endogenous NPF-bearing partners. Forcibly sequestering cytosolic EPS15 in genome-edited cells with nanobodies tethered to early endosomes or mitochondria changes the subcellular location and availability of EPS15. This combined approach has strong effects on clathrin coat structure and function by dictating the stability of AP-2 assemblies at the plasma membrane.
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Affiliation(s)
- Linton M Traub
- Department of Cell Biology, School of Medicine, University of Pittsburgh, Pittsburgh, United States
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15
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Bertschmann J, Thalappilly S, Riabowol K. The ING1a model of rapid cell senescence. Mech Ageing Dev 2019; 177:109-117. [DOI: 10.1016/j.mad.2018.06.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2018] [Revised: 05/21/2018] [Accepted: 06/16/2018] [Indexed: 12/17/2022]
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16
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Zuidema A, Wang W, Kreft M, Te Molder L, Hoekman L, Bleijerveld OB, Nahidiazar L, Janssen H, Sonnenberg A. Mechanisms of integrin αVβ5 clustering in flat clathrin lattices. J Cell Sci 2018; 131:jcs221317. [PMID: 30301780 DOI: 10.1242/jcs.221317] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 09/27/2018] [Indexed: 12/17/2023] Open
Abstract
The family of integrin transmembrane receptors is essential for the normal function of multicellular organisms by facilitating cell-extracellular matrix adhesion. The vitronectin-binding integrin αVβ5 localizes to focal adhesions (FAs) as well as poorly characterized flat clathrin lattices (FCLs). Here, we show that, in human keratinocytes, αVβ5 is predominantly found in FCLs, and formation of the αVβ5-containing FCLs requires the presence of vitronectin as ligand, Ca2+, and the clathrin adaptor proteins ARH (also known as LDLRAP1), Numb and EPS15/EPS15L1. Integrin chimeras, containing the extracellular and transmembrane domains of β5 and the cytoplasmic domains of β1 or β3, almost exclusively localize in FAs. Interestingly, lowering actomyosin-mediated contractility promotes integrin redistribution to FLCs in an integrin tail-dependent manner, while increasing cellular tension favors αVβ5 clustering in FAs. Our findings strongly indicate that clustering of integrin αVβ5 in FCLs is dictated by the β5 subunit cytoplasmic domain, cellular tension and recruitment of specific adaptor proteins to the β5 subunit cytoplasmic domains.
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Affiliation(s)
- Alba Zuidema
- Division of Cell Biology I, The Netherlands Cancer Institute, Plesmanlaan 121, Amsterdam 1066 CX, The Netherlands
| | - Wei Wang
- Division of Cell Biology I, The Netherlands Cancer Institute, Plesmanlaan 121, Amsterdam 1066 CX, The Netherlands
| | - Maaike Kreft
- Division of Cell Biology I, The Netherlands Cancer Institute, Plesmanlaan 121, Amsterdam 1066 CX, The Netherlands
| | - Lisa Te Molder
- Division of Cell Biology I, The Netherlands Cancer Institute, Plesmanlaan 121, Amsterdam 1066 CX, The Netherlands
| | - Liesbeth Hoekman
- Mass spectrometry/Proteomics Facility, The Netherlands Cancer Institute, Plesmanlaan 121, Amsterdam 1066 CX, The Netherlands
| | - Onno B Bleijerveld
- Mass spectrometry/Proteomics Facility, The Netherlands Cancer Institute, Plesmanlaan 121, Amsterdam 1066 CX, The Netherlands
| | - Leila Nahidiazar
- Division of Cell Biology I, The Netherlands Cancer Institute, Plesmanlaan 121, Amsterdam 1066 CX, The Netherlands
| | - Hans Janssen
- Electron Microscopy Facility, The Netherlands Cancer Institute, Plesmanlaan 121, Amsterdam 1066 CX, The Netherlands
| | - Arnoud Sonnenberg
- Division of Cell Biology I, The Netherlands Cancer Institute, Plesmanlaan 121, Amsterdam 1066 CX, The Netherlands
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17
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Predescu D, Qin S, Patel M, Bardita C, Bhalli R, Predescu S. Epsin15 Homology Domains: Role in the Pathogenesis of Pulmonary Arterial Hypertension. Front Physiol 2018; 9:1393. [PMID: 30333761 PMCID: PMC6176378 DOI: 10.3389/fphys.2018.01393] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Accepted: 09/13/2018] [Indexed: 12/24/2022] Open
Abstract
Intersectin-1s (ITSN) deficiency and expression of a biologically active ITSN fragment, result of granzyme B cleavage under inflammatory conditions associated with pulmonary arterial hypertension (PAH), are characteristics of lung tissue of human and animal models of PAH. Recently, we have shown that this ITSN fragment comprising two Epsin15 homology domains (EHITSN) triggers endothelial cell (EC) proliferation and the plexiform arteriopathy in PAH. Limited evidence also indicates that the EH domains of endocytic proteins such as ITSN, upregulate compensatory endocytic pathways in cells with impaired vesicular trafficking. Thus, we sought to investigate whether the EHITSN may be involved in this compensatory mechanism for improving the EC endocytic dysfunction induced by ITSN deficiency and possibly contribute to PAH pathogenesis. We used stably-transfected human pulmonary artery ECs expressing the Myc-EHITSN (ECEH-ITSN) and ITSN knockout heterozygous mice (K0ITSN+/-) transduced with the Myc-EHITSN, in conjunction with functional assays: the biotin assay for caveolae internalization and 8 nm gold (Au)- and dinitrophenylated (DNP)-albumin perfusion of murine lung microvasculature. Pulmonary artery ECs of PAH patients (ECPAH), ITSN knockdown ECs (ECKD-ITSN), the monocrotaline (MCT)-induced mouse and rat models of PAH, as well as untreated animals, served as controls. ELISA via streptavidin-HRP or anti-DNP antibody (Ab), applied on ECs and lung lysates indicated greater than 30% increase in biotin internalization in ECEH-ITSN compared to ECCtrl. Despite their endocytic deficiency, ECPAH internalized biotin similar to ECCtrl which is twofold higher compared to ECKD-ITSN. Moreover, the lung microvascular bed of Myc-EHITSN-transduced mice and MCT-treated animals showed greater than twofold increase in DNP-BSA transendothelial transport, all compared to untreated controls. Electron microscopy (EM) revealed the increased occurrence of non-conventional endocytic/transcytotic structures (i.e., caveolae clusters, tubulo-vesicular and enlarged endocytic structures, membranous rings), usually underrepresented. Most of these structures were labeled by Au-BSA, consistent with their involvement in the transendothelial transport. Furthermore, ITSN deficiency and EHITSN expression alter the subcellular localization of the EH-binding protein 1 (EHBP1) and cortical actin organization, altogether supporting the increase occurrence/trafficking of the alternative endocytic structures. Thus, the EHITSN by shifting the physiological vesicular (caveolae) transport toward the alternative endocytic pathways is a significant contributor to the dysfunctional molecular phenotype of ECPAH.
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Affiliation(s)
- Dan Predescu
- Division of Pulmonary Medicine, Critical Care and Sleep Medicine, Department of Internal Medicine, Rush Medical College, Rush University, Chicago, IL, United States
| | - Shanshan Qin
- Division of Pulmonary Medicine, Critical Care and Sleep Medicine, Department of Internal Medicine, Rush Medical College, Rush University, Chicago, IL, United States
| | - Monal Patel
- Division of Pulmonary Medicine, Critical Care and Sleep Medicine, Department of Internal Medicine, Rush Medical College, Rush University, Chicago, IL, United States
| | - Cristina Bardita
- Division of Pulmonary Medicine, Critical Care and Sleep Medicine, Department of Internal Medicine, Rush Medical College, Rush University, Chicago, IL, United States
| | - Rabia Bhalli
- Division of Pulmonary Medicine, Critical Care and Sleep Medicine, Department of Internal Medicine, Rush Medical College, Rush University, Chicago, IL, United States
| | - Sanda Predescu
- Division of Pulmonary Medicine, Critical Care and Sleep Medicine, Department of Internal Medicine, Rush Medical College, Rush University, Chicago, IL, United States
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18
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Milovanovic D, Wu Y, Bian X, De Camilli P. A liquid phase of synapsin and lipid vesicles. Science 2018; 361:604-607. [PMID: 29976799 DOI: 10.1126/science.aat5671] [Citation(s) in RCA: 303] [Impact Index Per Article: 50.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Accepted: 06/25/2018] [Indexed: 12/14/2022]
Abstract
Neurotransmitter-containing synaptic vesicles (SVs) form tight clusters at synapses. These clusters act as a reservoir from which SVs are drawn for exocytosis during sustained activity. Several components associated with SVs that are likely to help form such clusters have been reported, including synapsin. Here we found that synapsin can form a distinct liquid phase in an aqueous environment. Other scaffolding proteins could coassemble into this condensate but were not necessary for its formation. Importantly, the synapsin phase could capture small lipid vesicles. The synapsin phase rapidly disassembled upon phosphorylation by calcium/calmodulin-dependent protein kinase II, mimicking the dispersion of synapsin 1 that occurs at presynaptic sites upon stimulation. Thus, principles of liquid-liquid phase separation may apply to the clustering of SVs at synapses.
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Affiliation(s)
- Dragomir Milovanovic
- Departments of Neuroscience and Cell Biology, Howard Hughes Medical Institute, Kavli Institute for Neuroscience, Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven, CT, USA
| | - Yumei Wu
- Departments of Neuroscience and Cell Biology, Howard Hughes Medical Institute, Kavli Institute for Neuroscience, Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven, CT, USA
| | - Xin Bian
- Departments of Neuroscience and Cell Biology, Howard Hughes Medical Institute, Kavli Institute for Neuroscience, Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven, CT, USA
| | - Pietro De Camilli
- Departments of Neuroscience and Cell Biology, Howard Hughes Medical Institute, Kavli Institute for Neuroscience, Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven, CT, USA.
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19
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Gryaznova T, Gubar O, Burdyniuk M, Kropyvko S, Rynditch A. WIP/ITSN1 complex is involved in cellular vesicle trafficking and formation of filopodia-like protrusions. Gene 2018; 674:49-56. [PMID: 29958948 DOI: 10.1016/j.gene.2018.06.078] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 06/24/2018] [Indexed: 01/12/2023]
Abstract
WIP (WASP interacting protein) together with N-WASP (neural Wiskott-Aldrich syndrome protein) regulates actin polymerization that is crucial for invadopodia and filopodia formation. Recently, we reported the WIP interaction with ITSN1 which is highly implicated in endo-/exocytosis, apoptosis, mitogenic signaling and cytoskeleton rearrangements. Here we demonstrate that the WIP/ITSN1 complex is involved in the transferrin receptor recycling and partially co-localizes with a marker of the fast recycling endosomes, RAB4. Moreover, ITSN1 recruits WIP to RAB4-positive vesicles upon overexpression. Our data indicate that WIP enhances the interaction of N-WASP with ITSN1 and promotes ITSN1/β-actin association. Moreover, the WIP/ITSN1-L complex facilitates formation of filopodia-like protrusions in MCF-7 cells. Thus, WIP/ITSN1 complex is involved in the cellular vesicle trafficking and actin-dependent membrane processes.
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Affiliation(s)
- Tetyana Gryaznova
- Institute of Molecular Biology and Genetics, 150 Zabolotnogo Street, Kyiv 03680, Ukraine.
| | - Olga Gubar
- Institute of Molecular Biology and Genetics, 150 Zabolotnogo Street, Kyiv 03680, Ukraine
| | - Mariia Burdyniuk
- Institute of Molecular Biology and Genetics, 150 Zabolotnogo Street, Kyiv 03680, Ukraine
| | - Sergii Kropyvko
- Institute of Molecular Biology and Genetics, 150 Zabolotnogo Street, Kyiv 03680, Ukraine
| | - Alla Rynditch
- Institute of Molecular Biology and Genetics, 150 Zabolotnogo Street, Kyiv 03680, Ukraine
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20
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Dergai O, Dergai M, Rynditch A. Ubiquitin-ligase AIP4 controls differential ubiquitination and stability of isoforms of the scaffold protein ITSN1. FEBS Lett 2018; 592:2259-2267. [PMID: 29851086 DOI: 10.1002/1873-3468.13118] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 05/12/2018] [Accepted: 05/17/2018] [Indexed: 11/07/2022]
Abstract
At present, the role of ubiquitination of cargoes internalized from the plasma membrane is better understood than the consequences of ubiquitination of proteins comprising the endocytic machinery. Here, we show that the E3 ubiquitin ligase AIP4/ITCH contributes to the differential ubiquitination of isoforms of the endocytic scaffold protein intersectin1 (ITSN1). The major isoform ITSN1-s is monoubiquitinated, whereas the minor one, ITSN1-22a undergoes a combination of mono- and oligoubiquitination. The monoubiquitination is required for ITSN1-s stability, whereas the oligoubiquitination of ITSN1-22a causes its proteasomal degradation. This explains the observed low abundance of the minor isoform in cells. Thus, different modes of ubiquitination regulated by AIP4 have opposite effects on ITSN1 isoform stability.
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Affiliation(s)
- Oleksandr Dergai
- Institute of Molecular Biology and Genetics, The National Academy of Science of Ukraine, Kyiv, Ukraine
| | - Mykola Dergai
- Institute of Molecular Biology and Genetics, The National Academy of Science of Ukraine, Kyiv, Ukraine
| | - Alla Rynditch
- Institute of Molecular Biology and Genetics, The National Academy of Science of Ukraine, Kyiv, Ukraine
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21
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Intersectin goes nuclear: secret life of an endocytic protein. Biochem J 2018; 475:1455-1472. [PMID: 29599122 DOI: 10.1042/bcj20170897] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2017] [Revised: 03/22/2018] [Accepted: 03/26/2018] [Indexed: 01/22/2023]
Abstract
Intersectin 1-short (ITSN1-s) is a 1220 amino acid ubiquitously expressed scaffold protein presenting a multidomain structure that allows to spatiotemporally regulate the functional interaction of a plethora of proteins. Besides its well-established role in endocytosis, ITSN1-s is involved in the regulation of cell signaling and is implicated in tumorigenesis processes, although the signaling pathways involved are still poorly understood. Here, we identify ITSN1-s as a nucleocytoplasmic trafficking protein. We show that, by binding to importin (IMP)α, a small fraction of ITSN1-s localizes in the cell nucleus at the steady state, where it preferentially associates with the nuclear envelope and interacts with lamin A/C. However, upon pharmacological ablation of chromosome region maintenance 1 (CRM-1)-dependent nuclear export pathway, the protein accumulates into the nucleus, thus revealing its moonlighting nature. Analysis of deletion mutants revealed that the coiled coil (CC) and Src homology (SH3) regions play the major role in its nucleocytoplasmic shuttling. While no evidence of nuclear localization signal (NLS) was detected in the CC region, a functional bipartite NLS was identified within the SH3D region of ITSN1-s (RKKNPGGWWEGELQARGKKRQIGW-1127), capable of conferring energy-dependent nuclear accumulation to reporter proteins and whose mutational ablation affects nuclear import of the whole SH3 region. Thus, ITSN1-s is an endocytic protein, which shuttles between the nucleus and the cytoplasm in a CRM-1- and IMPα-dependent fashion.
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22
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Ioannou MS, Kulasekaran G, Fotouhi M, Morein JJ, Han C, Tse S, Nossova N, Han T, Mannard E, McPherson PS. Intersectin-s interaction with DENND2B facilitates recycling of epidermal growth factor receptor. EMBO Rep 2017; 18:2119-2130. [PMID: 29030480 DOI: 10.15252/embr.201744034] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2017] [Revised: 09/19/2017] [Accepted: 09/20/2017] [Indexed: 11/09/2022] Open
Abstract
Epidermal growth factor (EGF) activates the EGF receptor (EGFR) and stimulates its internalization and trafficking to lysosomes for degradation. However, a percentage of EGFR undergoes ligand-independent endocytosis and is rapidly recycled back to the plasma membrane. Importantly, alterations in EGFR recycling are a common hallmark of cancer, and yet, our understanding of the machineries controlling the fate of endocytosed EGFR is incomplete. Intersectin-s is a multi-domain adaptor protein that is required for internalization of EGFR Here, we discover that intersectin-s binds DENND2B, a guanine nucleotide exchange factor for the exocytic GTPase Rab13, and this interaction promotes recycling of ligand-free EGFR to the cell surface. Intriguingly, upon EGF treatment, DENND2B is phosphorylated by protein kinase D and dissociates from intersectin-s, allowing for receptor targeting to degradation. Our study thus reveals a novel mechanism controlling the fate of internalized EGFR with important implications for cancer.
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Affiliation(s)
- Maria S Ioannou
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Gopinath Kulasekaran
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Maryam Fotouhi
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Justin J Morein
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Chanshuai Han
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Sarah Tse
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Nadya Nossova
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Tony Han
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Erin Mannard
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Peter S McPherson
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
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23
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Jeganathan N, Predescu D, Predescu S. Intersectin-1s deficiency in pulmonary pathogenesis. Respir Res 2017; 18:168. [PMID: 28874189 PMCID: PMC5585975 DOI: 10.1186/s12931-017-0652-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 08/28/2017] [Indexed: 02/07/2023] Open
Abstract
Intersectin-1s (ITSN-1s), a multidomain adaptor protein, plays a vital role in endocytosis, cytoskeleton rearrangement and cell signaling. Recent studies have demonstrated that deficiency of ITSN-1s is a crucial early event in pulmonary pathogenesis. In lung cancer, ITSN-1s deficiency impairs Eps8 ubiquitination and favors Eps8-mSos1 interaction which activates Rac1 leading to enhanced lung cancer cell proliferation, migration and metastasis. Restoring ITSN-1s deficiency in lung cancer cells facilitates cytoskeleton changes favoring mesenchymal to epithelial transformation and impairs lung cancer progression. ITSN-1s deficiency in acute lung injury leads to impaired endocytosis which leads to ubiquitination and degradation of growth factor receptors such as Alk5. This deficiency is counterbalanced by microparticles which, via paracrine effects, transfer Alk5/TGFβRII complex to non-apoptotic cells. In the presence of ITSN-1s deficiency, Alk5-restored cells signal via Erk1/2 MAPK pathway leading to restoration and repair of lung architecture. In inflammatory conditions such as pulmonary artery hypertension, ITSN-1s full length protein is cleaved by granzyme B into EHITSN and SH3A-EITSN fragments. The EHITSN fragment leads to pulmonary cell proliferation via activation of p38 MAPK and Elk-1/c-Fos signaling. In vivo, ITSN-1s deficient mice transduced with EHITSN plasmid develop pulmonary vascular obliteration and plexiform lesions consistent with pathological findings seen in severe pulmonary arterial hypertension. These novel findings have significantly contributed to understanding the mechanisms and pathogenesis involved in pulmonary pathology. As demonstrated in these studies, genetically modified ITSN-1s expression mouse models will be a valuable tool to further advance our understanding of pulmonary pathology and lead to novel targets for treating these conditions.
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Affiliation(s)
| | - Dan Predescu
- Department of Pharmacology and Division of Pulmonary and Critical Care Medicine, Rush University, 1750 W. Harrison Street, 1415 Jelke, Chicago, IL, 60612, USA
| | - Sanda Predescu
- Department of Pharmacology and Division of Pulmonary and Critical Care Medicine, Rush University Medical Center and Rush Medical College, 1750 W. Harrison Street, 1535 Jelke, Chicago, IL, 60612, USA
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24
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Hernández-Vásquez MN, Adame-García SR, Hamoud N, Chidiac R, Reyes-Cruz G, Gratton JP, Côté JF, Vázquez-Prado J. Cell adhesion controlled by adhesion G protein-coupled receptor GPR124/ADGRA2 is mediated by a protein complex comprising intersectins and Elmo-Dock. J Biol Chem 2017; 292:12178-12191. [PMID: 28600358 DOI: 10.1074/jbc.m117.780304] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 05/30/2017] [Indexed: 11/06/2022] Open
Abstract
Developmental angiogenesis and the maintenance of the blood-brain barrier involve endothelial cell adhesion, which is linked to cytoskeletal dynamics. GPR124 (also known as TEM5/ADGRA2) is an adhesion G protein-coupled receptor family member that plays a pivotal role in brain angiogenesis and in ensuring a tight blood-brain barrier. However, the signaling properties of GPR124 remain poorly defined. Here, we show that ectopic expression of GPR124 promotes cell adhesion, additive to extracellular matrix-dependent effect, coupled with filopodia and lamellipodia formation and an enrichment of a pool of the G protein-coupled receptor at actin-rich cellular protrusions containing VASP, a filopodial marker. Accordingly, GPR124-expressing cells also displayed increased activation of both Rac and Cdc42 GTPases. Mechanistically, we uncover novel direct interactions between endogenous GPR124 and the Rho guanine nucleotide exchange factors Elmo/Dock and intersectin (ITSN). Small fragments of either Elmo or ITSN1 that bind GPR124 blocked GPR124-induced cell adhesion. In addition, Gβγ interacts with the C-terminal tail of GPR124 and promotes the formation of a GPR124-Elmo complex. Furthermore, GPR124 also promotes the activation of the Elmo-Dock complex, as measured by Elmo phosphorylation on a conserved C-terminal tyrosine residue. Interestingly, Elmo and ITSN1 also interact with each other independently of their GPR124-recognition regions. Moreover, endogenous phospho-Elmo and ITSN1 co-localize with GPR124 at lamellipodia of adhering endothelial cells, where GPR124 expression contributes to polarity acquisition during wound healing. Collectively, our results indicate that GPR124 promotes cell adhesion via Elmo-Dock and ITSN. This constitutes a previously unrecognized complex formed of atypical and conventional Rho guanine nucleotide exchange factors for Rac and Cdc42 that is putatively involved in GPR124-dependent angiogenic responses.
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Affiliation(s)
- Magda Nohemí Hernández-Vásquez
- Department of Pharmacology, Center for Research and Advanced Studies of the National Polytechnic Institute (CINVESTAV-IPN), Mexico City 14740, Mexico
| | - Sendi Rafael Adame-García
- Department of Cell Biology, Center for Research and Advanced Studies of the National Polytechnic Institute (CINVESTAV-IPN), Mexico City 14740, Mexico
| | - Noumeira Hamoud
- Institut de Recherches Cliniques de Montréal, Université de Montréal, Montreal, Quebec H3T 1J4, Canada
| | - Rony Chidiac
- Department of Pharmacology, Faculty of Medicine, Université de Montréal, Montreal, Quebec H3T 1J4, Canada
| | - Guadalupe Reyes-Cruz
- Department of Cell Biology, Center for Research and Advanced Studies of the National Polytechnic Institute (CINVESTAV-IPN), Mexico City 14740, Mexico
| | - Jean Philippe Gratton
- Department of Pharmacology, Faculty of Medicine, Université de Montréal, Montreal, Quebec H3T 1J4, Canada
| | - Jean-François Côté
- Institut de Recherches Cliniques de Montréal, Université de Montréal, Montreal, Quebec H3T 1J4, Canada
| | - José Vázquez-Prado
- Department of Pharmacology, Center for Research and Advanced Studies of the National Polytechnic Institute (CINVESTAV-IPN), Mexico City 14740, Mexico.
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25
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Herrero-Garcia E, O'Bryan JP. Intersectin scaffold proteins and their role in cell signaling and endocytosis. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1864:23-30. [PMID: 27746143 DOI: 10.1016/j.bbamcr.2016.10.005] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Accepted: 10/08/2016] [Indexed: 11/29/2022]
Abstract
Intersectins (ITSNs) are a family of multi-domain proteins involved in regulation of diverse cellular pathways. These scaffold proteins are well known for regulating endocytosis but also play important roles in cell signaling pathways including kinase regulation and Ras activation. ITSNs participate in several human cancers, such as neuroblastomas and glioblastomas, while their downregulation is associated with lung injury. Alterations in ITSN expression have been found in neurodegenerative diseases such as Down Syndrome and Alzheimer's disease. Binding proteins for ITSNs include endocytic regulatory factors, cytoskeleton related proteins (i.e. actin or dynamin), signaling proteins as well as herpes virus proteins. This review will summarize recent studies on ITSNs, highlighting the importance of these scaffold proteins in the aforementioned processes.
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Affiliation(s)
- Erika Herrero-Garcia
- Department of Pharmacology, University of Illinois at Chicago, Chicago, IL 60612, USA; Jesse Brown VA Medical Center, Chicago, IL 60612, USA
| | - John P O'Bryan
- Department of Pharmacology, University of Illinois at Chicago, Chicago, IL 60612, USA; Jesse Brown VA Medical Center, Chicago, IL 60612, USA.
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26
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Snetkov X, Weisswange I, Pfanzelter J, Humphries AC, Way M. NPF motifs in the vaccinia virus protein A36 recruit intersectin-1 to promote Cdc42:N-WASP-mediated viral release from infected cells. Nat Microbiol 2016; 1:16141. [PMID: 27670116 DOI: 10.1038/nmicrobiol.2016.141] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 07/12/2016] [Indexed: 11/09/2022]
Abstract
During its egress, vaccinia virus transiently recruits AP-2 and clathrin after fusion with the plasma membrane. This recruitment polarizes the viral protein A36 beneath the virus, enhancing actin polymerization and the spread of infection. We now demonstrate that three NPF motifs in the C-terminus of A36 recruit AP-2 and clathrin by interacting directly with the Epsin15 homology domains of Eps15 and intersectin-1. A36 is the first identified viral NPF motif containing protein shown to interact with endocytic machinery. Vaccinia still induces actin tails in the absence of the A36 NPF motifs. Their loss, however, reduces the cell-to-cell spread of vaccinia. This is due to a significant reduction in virus release from infected cells, as the lack of intersectin-1 recruitment leads to a loss of Cdc42 activation, impairing N-WASP-driven Arp2/3-mediated actin polymerization. Our results suggest that initial A36-mediated virus release plays a more important role than A36-driven super-repulsion in promoting the cell-to-cell spread of vaccinia.
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Affiliation(s)
- Xenia Snetkov
- Cellular Signalling and Cytoskeletal Function Laboratory, The Francis Crick Institute, Lincoln's Inn Fields Laboratory, 44 Lincoln's Inn Fields, London WC2A 3LY, UK
| | - Ina Weisswange
- Cellular Signalling and Cytoskeletal Function Laboratory, The Francis Crick Institute, Lincoln's Inn Fields Laboratory, 44 Lincoln's Inn Fields, London WC2A 3LY, UK
| | - Julia Pfanzelter
- Cellular Signalling and Cytoskeletal Function Laboratory, The Francis Crick Institute, Lincoln's Inn Fields Laboratory, 44 Lincoln's Inn Fields, London WC2A 3LY, UK
| | - Ashley C Humphries
- Cellular Signalling and Cytoskeletal Function Laboratory, The Francis Crick Institute, Lincoln's Inn Fields Laboratory, 44 Lincoln's Inn Fields, London WC2A 3LY, UK
| | - Michael Way
- Cellular Signalling and Cytoskeletal Function Laboratory, The Francis Crick Institute, Lincoln's Inn Fields Laboratory, 44 Lincoln's Inn Fields, London WC2A 3LY, UK
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27
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Yu H, Wang MJ, Xuan NX, Shang ZC, Wu J. Molecular dynamics simulation of the interactions between EHD1 EH domain and multiple peptides. J Zhejiang Univ Sci B 2016; 16:883-96. [PMID: 26465136 DOI: 10.1631/jzus.b1500106] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
OBJECTIVE To provide essential information for peptide inhibitor design, the interactions of Eps15 homology domain of Eps15 homology domain-containing protein 1 (EHD1 EH domain) with three peptides containing NPF (asparagine-proline-phenylalanine), DPF (aspartic acid-proline-phenylalanine), and GPF (glycine-proline-phenylalanine) motifs were deciphered at the atomic level. The binding affinities and the underlying structure basis were investigated. METHODS Molecular dynamics (MD) simulations were performed on EHD1 EH domain/peptide complexes for 60 ns using the GROMACS package. The binding free energies were calculated and decomposed by molecular mechanics/generalized Born surface area (MM/GBSA) method using the AMBER package. The alanine scanning was performed to evaluate the binding hot spot residues using FoldX software. RESULTS The different binding affinities for the three peptides were affected dominantly by van der Waals interactions. Intermolecular hydrogen bonds provide the structural basis of contributions of van der Waals interactions of the flanking residues to the binding. CONCLUSIONS van der Waals interactions should be the main consideration when we design peptide inhibitors of EHD1 EH domain with high affinities. The ability to form intermolecular hydrogen bonds with protein residues can be used as the factor for choosing the flanking residues.
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Affiliation(s)
- Hua Yu
- Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Mao-jun Wang
- Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Nan-xia Xuan
- Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Zhi-cai Shang
- Department of Chemistry, Zhejiang University, Hangzhou 310027, China
| | - Jun Wu
- Department of Chemistry, Zhejiang University, Hangzhou 310027, China
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28
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Picas L, Gaits-Iacovoni F, Goud B. The emerging role of phosphoinositide clustering in intracellular trafficking and signal transduction. F1000Res 2016; 5. [PMID: 27092250 PMCID: PMC4821294 DOI: 10.12688/f1000research.7537.1] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/23/2016] [Indexed: 01/03/2023] Open
Abstract
Phosphoinositides are master regulators of multiple cellular processes: from vesicular trafficking to signaling, cytoskeleton dynamics, and cell growth. They are synthesized by the spatiotemporal regulated activity of phosphoinositide-metabolizing enzymes. The recent observation that some protein modules are able to cluster phosphoinositides suggests that alternative or complementary mechanisms might operate to stabilize the different phosphoinositide pools within cellular compartments. Herein, we discuss the different known and potential molecular players that are prone to engage phosphoinositide clustering and elaborate on how such a mechanism might take part in the regulation of intracellular trafficking and signal transduction.
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Affiliation(s)
- Laura Picas
- Centre de Biochimie Structurale, CNRS UMR 5048, INSERM U1054, Université de Montpellier, Montpellier, France
| | - Frederique Gaits-Iacovoni
- INSERM, UMR1048, Université Toulouse III, Institut des Maladies Métaboliques et Cardiovasculaires, Toulouse, France
| | - Bruno Goud
- Institut Curie, PSL Research University, CNRS UMR 144, Paris, France
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29
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Pilmore E, Hamilton KL. The Role of MicroRNAs in the Regulation of K(+) Channels in Epithelial Tissue. Front Physiol 2015; 6:352. [PMID: 26648872 PMCID: PMC4664832 DOI: 10.3389/fphys.2015.00352] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Accepted: 11/09/2015] [Indexed: 12/27/2022] Open
Abstract
Our understanding of the modulation of proteins has shifted in direction with the discovery of microRNAs (miRs) over twenty years ago. MiRs are now in the “limelight” as these non-coding pieces of RNA (generally ~22 nucleotides long) result in altered translation and function of proteins. Indeed, miRs are now reported to be potential biomarkers of disease. Epithelial K+ channels play many roles in electrolyte and fluid homeostasis of the human body and have been suggested to be therapeutic targets of disease. Interestingly, the role of miRs in modulating K+ channels of epithelial tissues is only emerging now. This minireview focuses on recent novel findings into the role of miRs in the regulation of K+ channels of epithelia.
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Affiliation(s)
- Elliot Pilmore
- Department of Physiology, Otago School of Medical Sciences, University of Otago Dunedin, New Zealand
| | - Kirk L Hamilton
- Department of Physiology, Otago School of Medical Sciences, University of Otago Dunedin, New Zealand
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30
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Yang X, Yan F, He Z, Liu S, Cheng Y, Wei K, Gan S, Yuan J, Wang S, Xiao Y, Ren K, Liu N, Hu X, Ding X, Hu X, Xiang S. ITSN2L Interacts with and Negatively Regulates RABEP1. Int J Mol Sci 2015; 16:28242-54. [PMID: 26633357 PMCID: PMC4691038 DOI: 10.3390/ijms161226091] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2015] [Revised: 10/28/2015] [Accepted: 11/02/2015] [Indexed: 01/26/2023] Open
Abstract
Intersectin-2Long (ITSN2L) is a multi-domain protein participating in endocytosis and exocytosis. In this study, RABEP1 was identified as a novel ITSN2L interacting protein using a yeast two-hybrid screen from a human brain cDNA library and this interaction, specifically involving the ITSN2L CC domain and RABEP1 CC3 regions, was further confirmed by in vitro GST (glutathione-S-transferase) pull-down and in vivo co-immunoprecipitation assays. Corroboratively, we observed that these two proteins co-localize in the cytoplasm of mammalian cells. Furthermore, over-expression of ITSN2L promotes RABEP1 degradation and represses RABEP1-enhanced endosome aggregation, indicating that ITSN2L acts as a negative regulator of RABEP1. Finally, we showed that ITSN2L and RABEP1 play opposite roles in regulating endocytosis. Taken together, our results indicate that ITSN2L interacts with RABEP1 and stimulates its degradation in regulation of endocytosis.
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Affiliation(s)
- Xiaoxu Yang
- Key Laboratory of Protein Chemistry and Developmental Biology of State Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, China.
| | - Feng Yan
- Key Laboratory of Protein Chemistry and Developmental Biology of State Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, China.
| | - Zhicheng He
- Key Laboratory of Protein Chemistry and Developmental Biology of State Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, China.
| | - Shan Liu
- Key Laboratory of Protein Chemistry and Developmental Biology of State Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, China.
| | - Yeqing Cheng
- Key Laboratory of Protein Chemistry and Developmental Biology of State Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, China.
| | - Ke Wei
- Key Laboratory of Protein Chemistry and Developmental Biology of State Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, China.
| | - Shiquan Gan
- Key Laboratory of Protein Chemistry and Developmental Biology of State Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, China.
| | - Jing Yuan
- Key Laboratory of Protein Chemistry and Developmental Biology of State Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, China.
| | - Shang Wang
- Key Laboratory of Protein Chemistry and Developmental Biology of State Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, China.
| | - Ye Xiao
- Key Laboratory of Protein Chemistry and Developmental Biology of State Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, China.
| | - Kaiqun Ren
- Key Laboratory of Protein Chemistry and Developmental Biology of State Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, China.
| | - Ning Liu
- Key Laboratory of Protein Chemistry and Developmental Biology of State Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, China.
| | - Xiang Hu
- Key Laboratory of Protein Chemistry and Developmental Biology of State Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, China.
| | - Xiaofeng Ding
- Key Laboratory of Protein Chemistry and Developmental Biology of State Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, China.
| | - Xingwang Hu
- Key Laboratory of Protein Chemistry and Developmental Biology of State Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, China.
- Department of Dermatology, Xiangya Hospital, Central South University, Changsha 410081, China.
| | - Shuanglin Xiang
- Key Laboratory of Protein Chemistry and Developmental Biology of State Ministry of Education, College of Life Sciences, Hunan Normal University, Changsha 410081, China.
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31
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Abstract
Endocytosis, the process whereby the plasma membrane invaginates to form vesicles, is essential for bringing many substances into the cell and for membrane turnover. The mechanism driving clathrin-mediated endocytosis (CME) involves > 50 different protein components assembling at a single location on the plasma membrane in a temporally ordered and hierarchal pathway. These proteins perform precisely choreographed steps that promote receptor recognition and clustering, membrane remodeling, and force-generating actin-filament assembly and turnover to drive membrane invagination and vesicle scission. Many critical aspects of the CME mechanism are conserved from yeast to mammals and were first elucidated in yeast, demonstrating that it is a powerful system for studying endocytosis. In this review, we describe our current mechanistic understanding of each step in the process of yeast CME, and the essential roles played by actin polymerization at these sites, while providing a historical perspective of how the landscape has changed since the preceding version of the YeastBook was published 17 years ago (1997). Finally, we discuss the key unresolved issues and where future studies might be headed.
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Affiliation(s)
- Bruce L Goode
- Brandeis University, Department of Biology, Rosenstiel Center, Waltham, Massachusetts 02454
| | - Julian A Eskin
- Brandeis University, Department of Biology, Rosenstiel Center, Waltham, Massachusetts 02454
| | - Beverly Wendland
- The Johns Hopkins University, Department of Biology, Baltimore, Maryland 21218
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32
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Bradford MK, Whitworth K, Wendland B. Pan1 regulates transitions between stages of clathrin-mediated endocytosis. Mol Biol Cell 2015; 26:1371-85. [PMID: 25631817 PMCID: PMC4454182 DOI: 10.1091/mbc.e14-11-1510] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
The Saccharomyces cerevisiae endocytic protein Pan1 is critical for coat interactions during three transitions of the endocytic pathway. Pan1 depletion arrests endocytosis and causes actin misregulation, leading to actin flares that are connected to the coat but not the membrane. The Pan1 central region is critical for endocytic and essential functions. Endocytosis is a well-conserved process by which cells invaginate small portions of the plasma membrane to create vesicles containing extracellular and transmembrane cargo proteins. Dozens of proteins and hundreds of specific binding interactions are needed to coordinate and regulate these events. Saccharomyces cerevisiae is a powerful model system with which to study clathrin-mediated endocytosis (CME). Pan1 is believed to be a scaffolding protein due to its interactions with numerous proteins that act throughout the endocytic process. Previous research characterized many Pan1 binding interactions, but due to Pan1's essential nature, the exact mechanisms of Pan1's function in endocytosis have been difficult to define. We created a novel Pan1-degron allele, Pan1-AID, in which Pan1 can be specifically and efficiently degraded in <1 h upon addition of the plant hormone auxin. The loss of Pan1 caused a delay in endocytic progression and weakened connections between the coat/actin machinery and the membrane, leading to arrest in CME. In addition, we determined a critical role for the central region of Pan1 in endocytosis and viability. The regions important for endocytosis and viability can be separated, suggesting that Pan1 may have a distinct role in the cell that is essential for viability.
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Affiliation(s)
| | - Karen Whitworth
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218
| | - Beverly Wendland
- Department of Biology, Johns Hopkins University, Baltimore, MD 21218
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33
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Zhang Y, Persson S, Hirst J, Robinson MS, van Damme D, Sánchez-Rodríguez C. Change your TPLATE, change your fate: plant CME and beyond. TRENDS IN PLANT SCIENCE 2015; 20:41-8. [PMID: 25278268 DOI: 10.1016/j.tplants.2014.09.002] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Revised: 09/03/2014] [Accepted: 09/04/2014] [Indexed: 05/05/2023]
Abstract
Clathrin-mediated endocytosis (CME) is the predominant and evolutionarily conserved pathway by which eukaryotes internalize cargoes (i.e., plasma membrane proteins, lipids, and extracellular material) that are engaged in a variety of processes. Initiation of CME relies on adaptor proteins, which precisely select the cargoes for internalization, recruit the clathrin cage, and start membrane curvature. The recently identified CME early adaptor complex, the TPLATE complex (TPC), is essential for CME in plants. Phylogenetic analyses suggest that the TPC evolved from an ancient protein complex involved in vesicle trafficking in early eukaryotes, which raises questions about CME evolution and adaptation within the eukaryotic Kingdoms. In this review, we focus on the early events of plant CME and explore evolutionary aspects related to CME in other eukaryotes.
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Affiliation(s)
- Yi Zhang
- Max-Planck-Institute for Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany
| | - Staffan Persson
- Max-Planck-Institute for Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany; ARC Centre of Excellence in Plant Cell Walls, School of Botany, University of Melbourne, Parkville 3010, VIC, Australia
| | - Jennifer Hirst
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, UK
| | - Margaret S Robinson
- Cambridge Institute for Medical Research, University of Cambridge, Cambridge CB2 0XY, UK
| | - Daniel van Damme
- Department of Plant Systems Biology, VIB, Technologiepark 927, B-9052 Gent, Belgium; Department of Plant Biotechnology and Bioinformatics, Gent University, B-9052 Gent, Belgium
| | - Clara Sánchez-Rodríguez
- Max-Planck-Institute for Molecular Plant Physiology, Am Mühlenberg 1, 14476 Potsdam-Golm, Germany.
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34
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Ding X, Yang Z, Zhou F, Hu X, Zhou C, Luo C, He Z, Liu Q, Li H, Yan F, Wang F, Xiang S, Zhang J. Human intersectin 2 (ITSN2) binds to Eps8 protein and enhances its degradation. BMB Rep 2014; 45:183-8. [PMID: 22449706 DOI: 10.5483/bmbrep.2012.45.3.183] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Participates in actin remodeling through Rac and receptor endocytosis via Rab5. Here, we used yeast two-hybrid system with Eps8 as bait to screen a human brain cDNA library. ITSN2 was identified as the novel binding factor of Eps8. The interaction between ITSN2 and Eps8 was demonstrated by the in vivo co-immunoprecipitation and colocalization assays and the in vitro GST pull-down assays. Furthermore, we mapped the interaction domains to the region between amino acids 260-306 of Eps8 and the coiled-coil domain of ITSN2. In addition, protein stability assays and immunofluorescence analysis showed ITSN2 overexpression induced the degradation of Eps8 proteins, which was markedly alleviated with the lysosome inhibitor NH4Cl treatment. Taken together, our results suggested ITSN2 interacts with Eps8 and stimulates the degradation of Eps8 proteins.
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Affiliation(s)
- Xiaofeng Ding
- Key Laboratory of Protein Chemistry and Development Biology of State Education Ministry of China, College of Life Science, Hunan Normal University, Changsha, China
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35
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Abstract
Dynamin is a large GTPase that mediates plasma membrane fission during clathrin-mediated endocytosis. Dynamin assembles into polymers on the necks of budding membranes in cells and has been shown to undergo GTP-dependent conformational changes that lead to membrane fission in vitro. Recent efforts have shed new light on the mechanisms of dynamin-mediated fission, yet exactly how dynamin performs this function in vivo is still not fully understood. Dynamin interacts with a number of proteins during the endocytic process. These interactions are mediated by the C-terminal proline-rich domain (PRD) of dynamin binding to SH3 domain-containing proteins. Three of these dynamin-binding partners (intersectin, amphiphysin and endophilin) have been shown to play important roles in the clathrin-mediated endocytosis process. They promote dynamin-mediated plasma membrane fission by regulating three important sequential steps in the process: recruitment of dynamin to sites of endocytosis; assembly of dynamin into a functional fission complex at the necks of clathrin-coated pits (CCPs); and regulation of dynamin-stimulated GTPase activity, a key requirement for fission.
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36
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Xie S, Naslavsky N, Caplan S. Diacylglycerol kinase α regulates tubular recycling endosome biogenesis and major histocompatibility complex class I recycling. J Biol Chem 2014; 289:31914-31926. [PMID: 25248744 DOI: 10.1074/jbc.m114.594291] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Major histocompatibility complex class I (MHC I) presents intracellular-derived peptides to cytotoxic T lymphocytes and its subcellular itinerary is important in regulating the immune response. While a number of diacylglycerol kinase isoforms have been implicated in clathrin-dependent internalization, MHC I lacks the typical motifs known to mediate clathrin-dependent endocytosis. Here we show that depletion of diacylglycerol kinase α (DGKα), a kinase devoid of a clathrin-dependent adaptor protein complex 2 binding site, caused a delay in MHC I recycling to the plasma membrane without affecting the rate of MHC I internalization. We demonstrate that DGKα knock-down causes accumulation of intracellular and surface MHC I, resulting from decreased degradation. Furthermore, we provide evidence that DGKα is required for the generation of phosphatidic acid required for tubular recycling endosome (TRE) biogenesis. Moreover, we show that DGKα forms a complex with the TRE hub protein, MICAL-L1. Given that MICAL-L1 and the F-BAR-containing membrane-tubulating protein Syndapin2 associate selectively with phosphatidic acid, we propose a positive feedback loop in which DGKα generates phosphatidic acid to drive its own recruitment to TRE via its interaction with MICAL-L1. Our data support a novel role for the involvement of DGKα in TRE biogenesis and MHC I recycling.
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Affiliation(s)
- Shuwei Xie
- Department of Biochemistry and Molecular Biology and the Fred and Pamela Buffett Cancer Center, The University of Nebraska Medical Center, Omaha, Nebraska 68198
| | - Naava Naslavsky
- Department of Biochemistry and Molecular Biology and the Fred and Pamela Buffett Cancer Center, The University of Nebraska Medical Center, Omaha, Nebraska 68198.
| | - Steve Caplan
- Department of Biochemistry and Molecular Biology and the Fred and Pamela Buffett Cancer Center, The University of Nebraska Medical Center, Omaha, Nebraska 68198
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Bardita C, Predescu D, Justice MJ, Petrache I, Predescu S. In vivo knockdown of intersectin-1s alters endothelial cell phenotype and causes microvascular remodeling in the mouse lungs. Apoptosis 2013; 18:57-76. [PMID: 23054079 PMCID: PMC3543613 DOI: 10.1007/s10495-012-0762-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Intersectin-1s (ITSN-1s) is a general endocytic protein involved in regulating lung vascular permeability and endothelial cells (ECs) survival, via MEK/Erk1/2MAPK signaling. To investigate the in vivo effects of ITSN-1s deficiency and the resulting ECs apoptosis on pulmonary vasculature and lung homeostasis, we used an ITSN-1s knocked-down (KDITSN) mouse generated by repeated delivery of a specific siRNA targeting ITSN-1 gene (siRNAITSN). Biochemical and histological analyses as well as electron microscopy (EM) revealed that acute KDITSN [3-days (3d) post-siRNAITSN treatment] inhibited Erk1/2MAPK pro-survival signaling, causing significant ECs apoptosis and lung injury; at 10d of KDITSN, caspase-3 activation was at peak, terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL)-positive ECs showed 3.4-fold increase, the mean linear intercept (MLI) showed 48 % augment and pulmonary microvessel density as revealed by aquaporin-1 staining (AQP-1) decreased by 30 %, all compared to controls; pulmonary function was altered. Concomitantly, expression of several growth factors known to activate Erk1/2MAPK and suppress Bad pro-apoptotic activity increased. KDITSN altered Smads activity, downstream of the transforming growth factor beta-receptor-1 (TβR1), as shown by subcellular fractionation and immunoblot analyses. Moreover, 24d post-siRNAITSN, surviving ECs became hyper-proliferative and apoptotic-resistant against ITSN-1s deficiency, as demonstrated by EM imaging, 5-bromo-deoxyuridine (BrdU) incorporation and Bad-Ser112/155 phosphorylation, respectively, leading to increased microvessel density and repair of the injured lungs, as well as matrix deposition. In sum, ECs endocytic dysfunction and apoptotic death caused by KDITSN contribute to the initial lung injury and microvascular loss, followed by endothelial phenotypic changes and microvascular remodeling in the remaining murine pulmonary microvascular bed.
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Affiliation(s)
- Cristina Bardita
- Department of Pharmacology, Rush University, 1735 W. Harrison St., Chicago, IL 60612, USA
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Humphries AC, Way M. The non-canonical roles of clathrin and actin in pathogen internalization, egress and spread. Nat Rev Microbiol 2013; 11:551-60. [PMID: 24020073 DOI: 10.1038/nrmicro3072] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The role of clathrin in pathogen entry has received much attention and has highlighted the adaptability of clathrin during internalization. Recent studies have now uncovered additional roles for clathrin and have put the spotlight on its role in pathogen spread. Here, we discuss the manipulation of clathrin by pathogens, with specific attention to the processes that occur at the plasma membrane. In the majority of cases, both clathrin and the actin cytoskeleton are hijacked, so we also examine the interplay between these two systems and their role during pathogen internalization, egress and spread.
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Affiliation(s)
- Ashley C Humphries
- Cancer Research UK London Research Institute, 44 Lincoln’s Inn Fields, London WC2A 3LY, UK
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39
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Srila W, Yamabhai M. Identification of Amino Acid Residues Responsible for the Binding to Anti-FLAG™ M2 Antibody Using a Phage Display Combinatorial Peptide Library. Appl Biochem Biotechnol 2013; 171:583-9. [DOI: 10.1007/s12010-013-0326-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2013] [Accepted: 06/10/2013] [Indexed: 12/12/2022]
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Stabilization of actin bundles by a dynamin 1/cortactin ring complex is necessary for growth cone filopodia. J Neurosci 2013; 33:4514-26. [PMID: 23467367 DOI: 10.1523/jneurosci.2762-12.2013] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Dynamin GTPase, a key molecule in endocytosis, mechanically severs the invaginated membrane upon GTP hydrolysis. Dynamin functions also in regulating actin cytoskeleton, but the mechanisms are yet to be defined. Here we show that dynamin 1, a neuronal isoform of dynamin, and cortactin form ring complexes, which twine around F-actin bundles and stabilize them. By negative-staining EM, dynamin 1-cortactin complexes appeared as "open" or "closed" rings depending on guanine nucleotide conditions. By pyrene actin assembly assay, dynamin 1 stimulated actin assembly in mouse brain cytosol. In vitro incubation of F-actin with both dynamin 1 and cortactin led to the formation of long and thick actin bundles, on which dynamin 1 and cortactin were periodically colocalized in puncta. A depolymerization assay revealed that dynamin 1 and cortactin increased the stability of actin bundles, most prominently in the presence of GTP. In rat cortical neurons and human neuroblastoma cell line, SH-SY5Y, both dynamin 1 and cortactin localized on actin filaments and the bundles at growth cone filopodia as revealed by immunoelectron microscopy. In SH-SY5Y cell, acute inhibition of dynamin 1 by application of dynamin inhibitor led to growth cone collapse. Cortactin knockdown also reduced growth cone filopodia. Together, our results strongly suggest that dynamin 1 and cortactin ring complex mechanically stabilizes F-actin bundles in growth cone filopodia. Thus, the GTPase-dependent mechanochemical enzyme property of dynamin is commonly used both in endocytosis and regulation of F-actin bundles by a dynamin 1-cortactin complex.
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41
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Vertebrate intersectin1 is repurposed to facilitate cortical midline connectivity and higher order cognition. J Neurosci 2013; 33:4055-65. [PMID: 23447614 DOI: 10.1523/jneurosci.4428-12.2013] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Invertebrate studies have highlighted a role for EH and SH3 domain Intersectin (Itsn) proteins in synaptic vesicle recycling and morphology. Mammals have two Itsn genes (Itsn1 and Itsn2), both of which can undergo alternative splicing to include DBL/PH and C2 domains not present in invertebrate Itsn proteins. To probe for specific and redundant functions of vertebrate Itsn genes, we generated Itsn1, Itsn2, and double mutant mice. While invertebrate mutants showed severe synaptic abnormalities, basal synaptic transmission and plasticity were unaffected at Schaffer CA1 synapses in mutant mice. Surprisingly, intercortical tracts-corpus callosum, ventral hippocampal, and anterior commissures-failed to cross the midline in mice lacking Itsn1, but not Itsn2. In contrast, tracts extending within hemispheres and those that decussate to more caudal brain segments appeared normal. Itsn1 mutant mice showed severe deficits in Morris water maze and contextual fear memory tasks, whereas mice lacking Itsn2 showed normal learning and memory. Thus, coincident with the acquisition of additional signaling domains, vertebrate Itsn1 has been functionally repurposed to also facilitate interhemispheric connectivity essential for high order cognitive functions.
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Bhattacharyya S, Mulherkar N, Chandran K. Endocytic pathways involved in filovirus entry: advances, implications and future directions. Viruses 2013; 4:3647-64. [PMID: 23342373 PMCID: PMC3528284 DOI: 10.3390/v4123647] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Detailed knowledge of the host-virus interactions that accompany filovirus entry into cells is expected to identify determinants of viral virulence and host range, and to yield targets for the development of antiviral therapeutics. While it is generally agreed that filovirus entry into the host cytoplasm requires viral internalization into acidic endosomal compartments and proteolytic cleavage of the envelope glycoprotein by endo/lysosomal cysteine proteases, our understanding of the specific endocytic pathways co-opted by filoviruses remains limited. This review addresses the current knowledge on cellular endocytic pathways implicated in filovirus entry, highlights the consensus as well as controversies, and discusses important remaining questions.
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Affiliation(s)
- Suchita Bhattacharyya
- Department of Atomic Energy-Centre for Excellence in Basic Sciences, University of Mumbai, Health Centre Building, Vidyanagari, Kalina, Santacruz East, Mumbai 400098, India; E-Mail:
| | - Nirupama Mulherkar
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, 1300 Morris Park Ave, Bronx, NY 10461, USA; E-Mail:
| | - Kartik Chandran
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, 1300 Morris Park Ave, Bronx, NY 10461, USA; E-Mail:
- Author to whom correspondence should be addressed; E-Mail: ; Tel.: +1-718-430-8851
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Emerging roles for intersectin (ITSN) in regulating signaling and disease pathways. Int J Mol Sci 2013; 14:7829-52. [PMID: 23574942 PMCID: PMC3645719 DOI: 10.3390/ijms14047829] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Revised: 04/02/2013] [Accepted: 04/03/2013] [Indexed: 01/10/2023] Open
Abstract
Intersectins (ITSNs) represent a family of multi-domain adaptor proteins that regulate endocytosis and cell signaling. ITSN genes are highly conserved and present in all metazoan genomes examined thus far. Lower eukaryotes have only one ITSN gene, whereas higher eukaryotes have two ITSN genes. ITSN was first identified as an endocytic scaffold protein, and numerous studies reveal a conserved role for ITSN in endocytosis. Subsequently, ITSNs were found to regulate multiple signaling pathways including receptor tyrosine kinases (RTKs), GTPases, and phosphatidylinositol 3-kinase Class 2beta (PI3KC2β). ITSN has also been implicated in diseases such as Down Syndrome (DS), Alzheimer Disease (AD), and other neurodegenerative disorders. This review summarizes the evolutionary conservation of ITSN, the latest research on the role of ITSN in endocytosis, the emerging roles of ITSN in regulating cell signaling pathways, and the involvement of ITSN in human diseases such as DS, AD, and cancer.
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44
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The ING1a tumor suppressor regulates endocytosis to induce cellular senescence via the Rb-E2F pathway. PLoS Biol 2013; 11:e1001502. [PMID: 23472054 PMCID: PMC3589274 DOI: 10.1371/journal.pbio.1001502] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2012] [Accepted: 01/24/2013] [Indexed: 02/07/2023] Open
Abstract
An age-associated isoform of ING1, ING1a, induces cell senescence by altering endocytosis, subsequently activating the retinoblastoma tumor suppressor. The INhibitor of Growth (ING) proteins act as type II tumor suppressors and epigenetic regulators, being stoichiometric members of histone acetyltransferase and histone deacetylase complexes. Expression of the alternatively spliced ING1a tumor suppressor increases >10-fold during replicative senescence. ING1a overexpression inhibits growth; induces a large flattened cell morphology and the expression of senescence-associated β-galactosidase; increases Rb, p16, and cyclin D1 levels; and results in the accumulation of senescence-associated heterochromatic foci. Here we identify ING1a-regulated genes and find that ING1a induces the expression of a disproportionate number of genes whose products encode proteins involved in endocytosis. Intersectin 2 (ITSN2) is most affected by ING1a, being rapidly induced >25-fold. Overexpression of ITSN2 independently induces expression of the p16 and p57KIP2 cyclin-dependent kinase inhibitors, which act to block Rb inactivation, acting as downstream effectors of ING1a. ITSN2 is also induced in normally senescing cells, consistent with elevated levels of ING1a inducing ITSN2 as part of a normal senescence program. Inhibition of endocytosis or altering the stoichiometry of endosome components such as Rab family members similarly induces senescence. Knockdown of ITSN2 also blocks the ability of ING1a to induce a senescent phenotype, confirming that ITSN2 is a major transducer of ING1a-induced senescence signaling. These data identify a pathway by which ING1a induces senescence and indicate that altered endocytosis activates the Rb pathway, subsequently effecting a senescent phenotype. Alternative splicing of several genes including the p16 and p53 tumor suppressors has been reported to increase during replicative senescence of normal diploid cells, but the biological functions of most alternative transcripts are unknown. We have found that a splicing product of the ING1 epigenetic regulator, ING1a, also increases during senescence; moreover, forced expression of ING1a at these levels in otherwise growth-competent cells can induce senescence. In this study we have determined that a major mechanism by which ING1a induces senescence is through inhibiting endocytosis; this subsequently activates the retinoblastoma (Rb) tumor suppressor pathway by increasing Rb levels and preventing its inactivation through multiple mechanisms. Our study also establishes a link between endocytosis and oxidative stress and suggests that multiple mechanisms that induce cellular senescence may do so by inhibiting normal endocytic processes, thereby affecting normal signal transduction pathways including those mitogenic pathways required for cell growth.
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Tsushima H, Malabarba MG, Confalonieri S, Senic-Matuglia F, Verhoef LGGC, Bartocci C, D'Ario G, Cocito A, Di Fiore PP, Salcini AE. A snapshot of the physical and functional wiring of the Eps15 homology domain network in the nematode. PLoS One 2013; 8:e56383. [PMID: 23424658 PMCID: PMC3570524 DOI: 10.1371/journal.pone.0056383] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2012] [Accepted: 01/13/2013] [Indexed: 12/12/2022] Open
Abstract
Protein interaction modules coordinate the connections within and the activity of intracellular signaling networks. The Eps15 Homology (EH) module, a protein-protein interaction domain that is a key feature of the EH-network, was originally identified in a few proteins involved in endocytosis and vesicle trafficking, and has subsequently also been implicated in actin reorganization, nuclear shuttling, and DNA repair. Here we report an extensive characterization of the physical connections and of the functional wirings of the EH-network in the nematode. Our data show that one of the major physiological roles of the EH-network is in neurotransmission. In addition, we found that the proteins of the network intersect, and possibly coordinate, a number of “territories” of cellular activity including endocytosis/recycling/vesicle transport, actin dynamics, general metabolism and signal transduction, ubiquitination/degradation of proteins, DNA replication/repair, and miRNA biogenesis and processing.
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Affiliation(s)
- Hanako Tsushima
- IFOM, Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy
| | - Maria Grazia Malabarba
- IFOM, Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy
- Dipartimento di Medicina, Chirurgia ed Odontoiatria, Università degli Studi di Milano, Milan, Italy
| | | | | | | | - Cristina Bartocci
- IFOM, Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy
| | - Giovanni D'Ario
- IFOM, Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy
| | - Andrea Cocito
- IFOM, Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy
| | - Pier Paolo Di Fiore
- IFOM, Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy
- Dipartimento di Medicina, Chirurgia ed Odontoiatria, Università degli Studi di Milano, Milan, Italy
- Istituto Europeo di Oncologia, Milan, Italy
- * E-mail: (PPDF); (AES)
| | - Anna Elisabetta Salcini
- IFOM, Fondazione Istituto FIRC di Oncologia Molecolare, Milan, Italy
- Biotech Research and Innovation Centre (BRIC), University of Copenhagen, Copenhagen, Denmark
- * E-mail: (PPDF); (AES)
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Gubar O, Morderer D, Tsyba L, Croisé P, Houy S, Ory S, Gasman S, Rynditch A. Intersectin: The Crossroad between Vesicle Exocytosis and Endocytosis. Front Endocrinol (Lausanne) 2013; 4:109. [PMID: 23986746 PMCID: PMC3753573 DOI: 10.3389/fendo.2013.00109] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2013] [Accepted: 08/09/2013] [Indexed: 12/24/2022] Open
Abstract
Intersectins (ITSNs) are a family of highly conserved proteins with orthologs from nematodes to mammals. In vertebrates, ITSNs are encoded by two genes (itsn1 and itsn2), which act as scaffolds that were initially discovered as proteins involved in endocytosis. Further investigation demonstrated that ITSN1 is also implicated in several other processes including regulated exocytosis, thereby suggesting a role for ITSN1 in the coupling between exocytosis and endocytosis in excitatory cells. Despite a high degree of conservation amongst orthologs, ITSN function is not so well preserved as they have acquired new properties during evolution. In this review, we will discuss the role of ITSN1 and its orthologs in exo- and endocytosis, in particular in neurons and neuroendocrine cells.
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Affiliation(s)
- Olga Gubar
- State Key Laboratory of Molecular and Cellular Biology, Institute of Molecular Biology and Genetics, Kyiv, Ukraine
- Department of Functional Genomics, Institute of Molecular Biology and Genetics, Kyiv, Ukraine
- Institut des Neurosciences Cellulaires et Intégratives, Centre National de la Recherche Scientifique-Unité Propre de Recherche 3212, Université de Strasbourg, Strasbourg, France
| | - Dmytro Morderer
- State Key Laboratory of Molecular and Cellular Biology, Institute of Molecular Biology and Genetics, Kyiv, Ukraine
- Department of Functional Genomics, Institute of Molecular Biology and Genetics, Kyiv, Ukraine
| | - Lyudmila Tsyba
- Department of Functional Genomics, Institute of Molecular Biology and Genetics, Kyiv, Ukraine
| | - Pauline Croisé
- Institut des Neurosciences Cellulaires et Intégratives, Centre National de la Recherche Scientifique-Unité Propre de Recherche 3212, Université de Strasbourg, Strasbourg, France
| | - Sébastien Houy
- Institut des Neurosciences Cellulaires et Intégratives, Centre National de la Recherche Scientifique-Unité Propre de Recherche 3212, Université de Strasbourg, Strasbourg, France
| | - Stéphane Ory
- Institut des Neurosciences Cellulaires et Intégratives, Centre National de la Recherche Scientifique-Unité Propre de Recherche 3212, Université de Strasbourg, Strasbourg, France
| | - Stéphane Gasman
- Institut des Neurosciences Cellulaires et Intégratives, Centre National de la Recherche Scientifique-Unité Propre de Recherche 3212, Université de Strasbourg, Strasbourg, France
| | - Alla Rynditch
- State Key Laboratory of Molecular and Cellular Biology, Institute of Molecular Biology and Genetics, Kyiv, Ukraine
- Department of Functional Genomics, Institute of Molecular Biology and Genetics, Kyiv, Ukraine
- *Correspondence: Alla Rynditch, Department of Functional Genomics, Institute of Molecular Biology and Genetics, 150, Zabolotnogo Street, 03680 Kyiv-143, Ukraine e-mail:
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Wong KA, Russo A, Wang X, Chen YJ, Lavie A, O'Bryan JP. A new dimension to Ras function: a novel role for nucleotide-free Ras in Class II phosphatidylinositol 3-kinase beta (PI3KC2β) regulation. PLoS One 2012; 7:e45360. [PMID: 23028960 PMCID: PMC3441633 DOI: 10.1371/journal.pone.0045360] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Accepted: 08/14/2012] [Indexed: 12/31/2022] Open
Abstract
The intersectin 1 (ITSN1) scaffold stimulates Ras activation on endocytic vesicles without activating classic Ras effectors. The identification of Class II phosphatidylinositol 3-kinase beta, PI3KC2β, as an ITSN1 target on vesicles and the presence of a Ras binding domain (RBD) in PI3KC2β suggests a role for Ras in PI3KC2β activation. Here, we demonstrate that nucleotide-free Ras negatively regulates PI3KC2β activity. PI3KC2β preferentially interacts in vivo with dominant-negative (DN) Ras, which possesses a low affinity for nucleotides. PI3KC2β interaction with DN Ras is disrupted by switch 1 domain mutations in Ras as well as RBD mutations in PI3KC2β. Using purified proteins, we demonstrate that the PI3KC2β-RBD directly binds nucleotide-free Ras in vitro and that this interaction is not disrupted by nucleotide addition. Finally, nucleotide-free Ras but not GTP-loaded Ras inhibits PI3KC2β lipid kinase activity in vitro. Our findings indicate that PI3KC2β interacts with and is regulated by nucleotide-free Ras. These data suggest a novel role for nucleotide-free Ras in cell signaling in which PI3KC2β stabilizes nucleotide-free Ras and that interaction of Ras and PI3KC2β mutually inhibit one another.
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Affiliation(s)
- Katy A. Wong
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, Illinois, United States of America
| | - Angela Russo
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, Illinois, United States of America
| | - Xuerong Wang
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, Illinois, United States of America
| | - Yun-Ju Chen
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, Illinois, United States of America
| | - Arnon Lavie
- Cancer Center, University of Illinois College of Medicine, Chicago, Illinois, United States of America
- Biochemistry and Molecular Genetics, University of Illinois College of Medicine, Chicago, Illinois, United States of America
| | - John P. O'Bryan
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, Illinois, United States of America
- Cancer Center, University of Illinois College of Medicine, Chicago, Illinois, United States of America
- Center for Cardiovascular Research, University of Illinois College of Medicine, Chicago, Illinois, United States of America
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Abstract
Neurons can sustain high rates of synaptic transmission without exhausting their supply of synaptic vesicles. This property relies on a highly efficient local endocytic recycling of synaptic vesicle membranes, which can be reused for hundreds, possibly thousands, of exo-endocytic cycles. Morphological, physiological, molecular, and genetic studies over the last four decades have provided insight into the membrane traffic reactions that govern this recycling and its regulation. These studies have shown that synaptic vesicle endocytosis capitalizes on fundamental and general endocytic mechanisms but also involves neuron-specific adaptations of such mechanisms. Thus, investigations of these processes have advanced not only the field of synaptic transmission but also, more generally, the field of endocytosis. This article summarizes current information on synaptic vesicle endocytosis with an emphasis on the underlying molecular mechanisms and with a special focus on clathrin-mediated endocytosis, the predominant pathway of synaptic vesicle protein internalization.
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Affiliation(s)
- Yasunori Saheki
- Department of Cell Biology, Howard Hughes Medical Institute and Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale University School of Medicine, New Haven, Connecticut 06510, USA
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Teckchandani A, Mulkearns EE, Randolph TW, Toida N, Cooper JA. The clathrin adaptor Dab2 recruits EH domain scaffold proteins to regulate integrin β1 endocytosis. Mol Biol Cell 2012; 23:2905-16. [PMID: 22648170 PMCID: PMC3408417 DOI: 10.1091/mbc.e11-12-1007] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Endocytic adaptor proteins facilitate cargo recruitment and clathrin-coated pit nucleation. The prototypical clathrin adaptor AP2 mediates cargo recruitment, maturation, and scission of the pit by binding cargo, clathrin, and accessory proteins, including the Eps-homology (EH) domain proteins Eps15 and intersectin. However, clathrin-mediated endocytosis of some cargoes proceeds efficiently in AP2-depleted cells. We found that Dab2, another endocytic adaptor, also binds to Eps15 and intersectin. Depletion of EH domain proteins altered the number and size of clathrin structures and impaired the endocytosis of the Dab2- and AP2-dependent cargoes, integrin β1 and transferrin receptor, respectively. To test the importance of Dab2 binding to EH domain proteins for endocytosis, we mutated the EH domain-binding sites. This mutant localized to clathrin structures with integrin β1, AP2, and reduced amounts of Eps15. Of interest, although integrin β1 endocytosis was impaired, transferrin receptor internalization was unaffected. Surprisingly, whereas clathrin structures contain both Dab2 and AP2, integrin β1 and transferrin localize in separate pits. These data suggest that Dab2-mediated recruitment of EH domain proteins selectively drives the internalization of the Dab2 cargo, integrin β1. We propose that adaptors may need to be bound to their cargo to regulate EH domain proteins and internalize efficiently.
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Affiliation(s)
- Anjali Teckchandani
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
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50
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Wong KA, Wilson J, Russo A, Wang L, Okur MN, Wang X, Martin NP, Scappini E, Carnegie GK, O'Bryan JP. Intersectin (ITSN) family of scaffolds function as molecular hubs in protein interaction networks. PLoS One 2012; 7:e36023. [PMID: 22558309 PMCID: PMC3338775 DOI: 10.1371/journal.pone.0036023] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Accepted: 03/28/2012] [Indexed: 11/29/2022] Open
Abstract
Members of the intersectin (ITSN) family of scaffold proteins consist of multiple modular domains, each with distinct ligand preferences. Although ITSNs were initially implicated in the regulation of endocytosis, subsequent studies have revealed a more complex role for these scaffold proteins in regulation of additional biochemical pathways. In this study, we performed a high throughput yeast two-hybrid screen to identify additional pathways regulated by these scaffolds. Although several known ITSN binding partners were identified, we isolated more than 100 new targets for the two mammalian ITSN proteins, ITSN1 and ITSN2. We present the characterization of several of these new targets which implicate ITSNs in the regulation of the Rab and Arf GTPase pathways as well as regulation of the disrupted in schizophrenia 1 (DISC1) interactome. In addition, we demonstrate that ITSN proteins form homomeric and heteromeric complexes with each other revealing an added level of complexity in the function of these evolutionarily conserved scaffolds.
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Affiliation(s)
- Katy A. Wong
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, Illinois, United States of America
- Center for Cardiovascular Research, University of Illinois College of Medicine, Chicago, Illinois, United States of America
- UIC Cancer Center, University of Illinois College of Medicine, Chicago, Illinois, United States of America
| | - Jessica Wilson
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, Illinois, United States of America
- Center for Cardiovascular Research, University of Illinois College of Medicine, Chicago, Illinois, United States of America
- UIC Cancer Center, University of Illinois College of Medicine, Chicago, Illinois, United States of America
| | - Angela Russo
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, Illinois, United States of America
- Center for Cardiovascular Research, University of Illinois College of Medicine, Chicago, Illinois, United States of America
- UIC Cancer Center, University of Illinois College of Medicine, Chicago, Illinois, United States of America
| | - Li Wang
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, Illinois, United States of America
| | - Mustafa Nazir Okur
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, Illinois, United States of America
- Center for Cardiovascular Research, University of Illinois College of Medicine, Chicago, Illinois, United States of America
- UIC Cancer Center, University of Illinois College of Medicine, Chicago, Illinois, United States of America
- Department of Biochemistry and Molecular Genetics, University of Illinois College of Medicine, Chicago, Illinois, United States of America
| | - Xuerong Wang
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, Illinois, United States of America
- Center for Cardiovascular Research, University of Illinois College of Medicine, Chicago, Illinois, United States of America
- UIC Cancer Center, University of Illinois College of Medicine, Chicago, Illinois, United States of America
| | - Negin P. Martin
- Laboratory of Neurobiology, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina, United States of America
| | - Erica Scappini
- Laboratory of Neurobiology, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, Research Triangle Park, North Carolina, United States of America
| | - Graeme K. Carnegie
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, Illinois, United States of America
| | - John P. O'Bryan
- Department of Pharmacology, University of Illinois College of Medicine, Chicago, Illinois, United States of America
- Center for Cardiovascular Research, University of Illinois College of Medicine, Chicago, Illinois, United States of America
- UIC Cancer Center, University of Illinois College of Medicine, Chicago, Illinois, United States of America
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