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Joseph I, Flores J, Farrell V, Davis J, Bianchi‐Smak J, Feng Q, Goswami S, Lin X, Wei Z, Tong K, Feng Z, Verzi MP, Bonder EM, Goldenring JR, Gao N. RAB11A and RAB11B control mitotic spindle function in intestinal epithelial progenitor cells. EMBO Rep 2023; 24:e56240. [PMID: 37424454 PMCID: PMC10481667 DOI: 10.15252/embr.202256240] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 06/20/2023] [Accepted: 06/27/2023] [Indexed: 07/11/2023] Open
Abstract
RAB11 small GTPases and associated recycling endosome have been localized to mitotic spindles and implicated in regulating mitosis. However, the physiological significance of such regulation has not been observed in mammalian tissues. We have used newly engineered mouse models to investigate intestinal epithelial renewal in the absence of single or double isoforms of RAB11 family members: Rab11a and Rab11b. Comparing with single knockouts, mice with compound ablation demonstrate a defective cell cycle entry and robust mitotic arrest followed by apoptosis, leading to a total penetrance of lethality within 3 days of gene ablation. Upon Rab11 deletion ex vivo, enteroids show abnormal mitotic spindle formation and cell death. Untargeted proteomic profiling of Rab11a and Rab11b immunoprecipitates has uncovered a shared interactome containing mitotic spindle microtubule regulators. Disrupting Rab11 alters kinesin motor KIF11 function and impairs bipolar spindle formation and cell division. These data demonstrate that RAB11A and RAB11B redundantly control mitotic spindle function and intestinal progenitor cell division, a mechanism that may be utilized to govern the homeostasis and renewal of other mammalian tissues.
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Affiliation(s)
- Ivor Joseph
- Department of Biological SciencesRutgers UniversityNewarkNJUSA
| | - Juan Flores
- Department of Biological SciencesRutgers UniversityNewarkNJUSA
| | | | - Justin Davis
- Department of Biological SciencesRutgers UniversityNewarkNJUSA
| | | | - Qiang Feng
- Department of Biological SciencesRutgers UniversityNewarkNJUSA
| | | | - Xiang Lin
- Department of Computer SciencesNew Jersey Institute of TechnologyNewarkNJUSA
| | - Zhi Wei
- Department of Computer SciencesNew Jersey Institute of TechnologyNewarkNJUSA
| | - Kevin Tong
- Department of GeneticsRutgers UniversityNew BrunswickNJUSA
| | - Zhaohui Feng
- Rutgers Cancer Institute of New JerseyNew BrunswickNJUSA
| | | | - Edward M Bonder
- Department of Biological SciencesRutgers UniversityNewarkNJUSA
| | - James R Goldenring
- Section of Surgical Sciences and Epithelial Biology CenterVanderbilt University Medical CenterNashvilleTNUSA
| | - Nan Gao
- Department of Biological SciencesRutgers UniversityNewarkNJUSA
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2
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Kisler K, Sagare AP, Lazic D, Bazzi S, Lawson E, Hsu CJ, Wang Y, Ramanathan A, Nelson AR, Zhao Z, Zlokovic BV. Anti-malaria drug artesunate prevents development of amyloid-β pathology in mice by upregulating PICALM at the blood-brain barrier. Mol Neurodegener 2023; 18:7. [PMID: 36707892 PMCID: PMC9883925 DOI: 10.1186/s13024-023-00597-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 01/13/2023] [Indexed: 01/28/2023] Open
Abstract
BACKGROUND PICALM is one of the most significant susceptibility factors for Alzheimer's disease (AD). In humans and mice, PICALM is highly expressed in brain endothelium. PICALM endothelial levels are reduced in AD brains. PICALM controls several steps in Aβ transcytosis across the blood-brain barrier (BBB). Its loss from brain endothelium in mice diminishes Aβ clearance at the BBB, which worsens Aβ pathology, but is reversible by endothelial PICALM re-expression. Thus, increasing PICALM at the BBB holds potential to slow down development of Aβ pathology. METHODS To identify a drug that could increase PICALM expression, we screened a library of 2007 FDA-approved drugs in HEK293t cells expressing luciferase driven by a human PICALM promoter, followed by a secondary mRNA screen in human Eahy926 endothelial cell line. In vivo studies with the lead hit were carried out in Picalm-deficient (Picalm+/-) mice, Picalm+/-; 5XFAD mice and Picalmlox/lox; Cdh5-Cre; 5XFAD mice with endothelial-specific Picalm knockout. We studied PICALM expression at the BBB, Aβ pathology and clearance from brain to blood, cerebral blood flow (CBF) responses, BBB integrity and behavior. RESULTS Our screen identified anti-malaria drug artesunate as the lead hit. Artesunate elevated PICALM mRNA and protein levels in Eahy926 endothelial cells and in vivo in brain capillaries of Picalm+/- mice by 2-3-fold. Artesunate treatment (32 mg/kg/day for 2 months) of 3-month old Picalm+/-; 5XFAD mice compared to vehicle increased brain capillary PICALM levels by 2-fold, and reduced Aβ42 and Aβ40 levels and Aβ and thioflavin S-load in the cortex and hippocampus, and vascular Aβ load by 34-51%. Artesunate also increased circulating Aβ42 and Aβ40 levels by 2-fold confirming accelerated Aβ clearance from brain to blood. Consistent with reduced Aβ pathology, treatment of Picalm+/-; 5XFAD mice with artesunate improved CBF responses, BBB integrity and behavior on novel object location and recognition, burrowing and nesting. Endothelial-specific knockout of PICALM abolished all beneficial effects of artesunate in 5XFAD mice indicating that endothelial PICALM is required for its therapeutic effects. CONCLUSIONS Artesunate increases PICALM levels and Aβ clearance at the BBB which prevents development of Aβ pathology and functional deficits in mice and holds potential for translation to human AD.
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Affiliation(s)
- Kassandra Kisler
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, 1501 San Pablo St, Los Angeles, CA 90089 USA
| | - Abhay P. Sagare
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, 1501 San Pablo St, Los Angeles, CA 90089 USA
| | - Divna Lazic
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, 1501 San Pablo St, Los Angeles, CA 90089 USA
| | - Sam Bazzi
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, 1501 San Pablo St, Los Angeles, CA 90089 USA
| | - Erica Lawson
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, 1501 San Pablo St, Los Angeles, CA 90089 USA
| | - Ching-Ju Hsu
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, 1501 San Pablo St, Los Angeles, CA 90089 USA
| | - Yaoming Wang
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, 1501 San Pablo St, Los Angeles, CA 90089 USA
| | - Anita Ramanathan
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, 1501 San Pablo St, Los Angeles, CA 90089 USA
| | - Amy R. Nelson
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, 1501 San Pablo St, Los Angeles, CA 90089 USA
| | - Zhen Zhao
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, 1501 San Pablo St, Los Angeles, CA 90089 USA
| | - Berislav V. Zlokovic
- Department of Physiology and Neuroscience and the Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, 1501 San Pablo St, Los Angeles, CA 90089 USA
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3
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Leite DM, Seifi M, Ruiz-Perez L, Nguemo F, Plomann M, Swinny JD, Battaglia G. Syndapin-2 mediated transcytosis of amyloid-ß across the blood-brain barrier. Brain Commun 2022; 4:fcac039. [PMID: 35233527 PMCID: PMC8882007 DOI: 10.1093/braincomms/fcac039] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Revised: 10/31/2021] [Accepted: 02/15/2022] [Indexed: 11/14/2022] Open
Abstract
A deficient transport of amyloid-β across the blood–brain barrier, and its diminished clearance from the brain, contribute to neurodegenerative and vascular pathologies, such as Alzheimer’s disease and cerebral amyloid angiopathy, respectively. At the blood–brain barrier, amyloid-β efflux transport is associated with the low-density lipoprotein receptor-related protein 1. However, the precise mechanisms governing amyloid-β transport across the blood–brain barrier, in health and disease, remain to be fully understood. Recent evidence indicates that the low-density lipoprotein receptor-related protein 1 transcytosis occurs through a tubulation-mediated mechanism stabilized by syndapin-2. Here, we show that syndapin-2 is associated with amyloid-β clearance via low-density lipoprotein receptor-related protein 1 across the blood–brain barrier. We further demonstrate that risk factors for Alzheimer’s disease, amyloid-β expression and ageing, are associated with a decline in the native expression of syndapin-2 within the brain endothelium. Our data reveals that syndapin-2-mediated pathway, and its balance with the endosomal sorting, are important for amyloid-β clearance proposing a measure to evaluate Alzheimer’s disease and ageing, as well as a target for counteracting amyloid-β build-up. Moreover, we provide evidence for the impact of the avidity of amyloid-β assemblies in their trafficking across the brain endothelium and in low-density lipoprotein receptor-related protein 1 expression levels, which may affect the overall clearance of amyloid-β across the blood–brain barrier.
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Affiliation(s)
- Diana M. Leite
- Department of Chemistry, University College London, London, United Kingdom
- Institute for the Physics of Living Systems, University College London, London, United Kingdom
| | - Mohsen Seifi
- Leicester School of Pharmacy, Faculty of Health and Life Sciences, De Montfort University, Leicester, United Kingdom
| | - Lorena Ruiz-Perez
- Department of Chemistry, University College London, London, United Kingdom
- Institute for the Physics of Living Systems, University College London, London, United Kingdom
| | - Filomain Nguemo
- Institute for Neurophysiology, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Markus Plomann
- Institute of Biochemistry, Faculty of Medicine, University of Cologne, Cologne, Germany
| | - Jerome D. Swinny
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, United Kingdom
| | - Giuseppe Battaglia
- Department of Chemistry, University College London, London, United Kingdom
- Institute for the Physics of Living Systems, University College London, London, United Kingdom
- Institute for Bioengineering of Catalonia (IBEC), The Barcelona Institute for Science and Technology (BIST), Barcelona, Spain
- Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, Spain
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4
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Zhang N, Lin J, Chew SY. Neural Cell Membrane-Coated Nanoparticles for Targeted and Enhanced Uptake by Central Nervous System Cells. ACS APPLIED MATERIALS & INTERFACES 2021; 13:55840-55850. [PMID: 34792341 DOI: 10.1021/acsami.1c16543] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Targeted drug delivery to specific neural cells within the central nervous system (CNS) plays important roles in treating neurological disorders, such as neurodegenerative (e.g., targeting neurons) and demyelinating diseases [e.g., targeting oligodendrocytes (OLs)]. However, the presence of many other cell types within the CNS, such as microglial and astrocytes, may lead to nonspecific uptake and subsequent side effects. As such, exploring an effective and targeted drug delivery system is of great necessity. Synthetic micro-/nanoparticles that have been coated with biologically derived cellular membranes have emerged as a new class of drug delivery vehicles. However, the use of neural cell-derived membrane coatings remains unexplored. Here, we utilized this technique and demonstrated the efficacy of targeted delivery by using four types of cell membranes that were derived from the CNS, namely, microglial, astrocytes, oligodendrocyte progenitor cells (OPCs), and cortical neurons. A successful cell membrane coating over poly(ε-caprolactone) nanoparticles (NPs) was confirmed using dynamic light scattering, zeta potential measurements, and transmission electron microscopy. Subsequently, an extensive screening of these cell membrane-coated NPs was carried out on various CNS cells. Results suggested that microglial and OLs were the most sensitive cell types toward cell membrane-coated NPs. Specifically, cell membrane-coated NPs significantly enhanced the uptake efficiency of OLs (p < 0.001). Additionally, a temporal uptake study indicated that the OLs took up microglial membrane-coated NPs (DPP-PCL-M Mem) most efficiently. Besides that, coating the NPs with four types of the CNS cell membrane did not result in obvious specific uptake in microglial but reduced the activation of microglial, especially for DPP-PCL-M Mem (p < 0.01). Taken together, DPP-PCL-M Mem were uptaken most efficiently in OLs and did not induce significant microglial activation and may be most suitable for CNS drug delivery applications.
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Affiliation(s)
- Na Zhang
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
| | - Junquan Lin
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
| | - Sing Yian Chew
- School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore 637459, Singapore
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore 308232, Singapore
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5
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Suzuki A, Iwata J. Molecular Regulatory Mechanism of Exocytosis in the Salivary Glands. Int J Mol Sci 2018; 19:E3208. [PMID: 30336591 PMCID: PMC6214078 DOI: 10.3390/ijms19103208] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Revised: 10/10/2018] [Accepted: 10/11/2018] [Indexed: 12/12/2022] Open
Abstract
Every day, salivary glands produce about 0.5 to 1.5 L of saliva, which contains salivary proteins that are essential for oral health. The contents of saliva, 0.3% proteins (1.5 to 4.5 g) in fluid, help prevent oral infections, provide lubrication, aid digestion, and maintain oral health. Acinar cells in the lobular salivary glands secrete prepackaged secretory granules that contain salivary components such as amylase, mucins, and immunoglobulins. Despite the important physiological functions of salivary proteins, we know very little about the regulatory mechanisms of their secretion via exocytosis, which is a process essential for the secretion of functional proteins, not only in salivary glands, but also in other secretory organs, including lacrimal and mammary glands, the pancreas, and prostate. In this review, we discuss recent findings that elucidate exocytosis by exocrine glands, especially focusing on the salivary glands, in physiological and pathological conditions.
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Affiliation(s)
- Akiko Suzuki
- Department of Diagnostic & Biomedical Sciences, The University of Texas Health Science Center at Houston School of Dentistry, Houston, TX 77054, USA.
- Center for Craniofacial Research, The University of Texas Health Science Center at Houston School of Dentistry, Houston, TX 77054, USA.
| | - Junichi Iwata
- Department of Diagnostic & Biomedical Sciences, The University of Texas Health Science Center at Houston School of Dentistry, Houston, TX 77054, USA.
- Center for Craniofacial Research, The University of Texas Health Science Center at Houston School of Dentistry, Houston, TX 77054, USA.
- Program of Biochemistry and Cell Biology, The University of Texas Graduate School of Biomedical Sciences at Houston, Houston, TX 77030, USA.
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6
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Zeng S, Wen KK, Workalemahu G, Sohn EH, Wu M, Chirco KR, Flamme-Wiese MJ, Liu X, Stone EM, Tucker BA, Mullins RF. Imidazole Compounds for Protecting Choroidal Endothelial Cells from Complement Injury. Sci Rep 2018; 8:13387. [PMID: 30190604 PMCID: PMC6127142 DOI: 10.1038/s41598-018-31846-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 08/28/2018] [Indexed: 02/06/2023] Open
Abstract
Age-related macular degeneration (AMD) is a common, blinding disease associated with increased complement system activity. Eyes with AMD show elevated accumulation of the membrane attack complex (MAC) in the choriocapillaris and degeneration of macular choriocapillaris endothelial cells (ECs). Thus, one could reasonably conclude that the endothelial cell death that occurs in AMD is due to injury by the MAC. We therefore sought to identify strategies for protecting ECs against MAC lysis. RF/6A endothelial cells were pre-incubated with a library of FDA-approved small molecules, followed by incubation with complement intact human serum quantification of cell death. Two closely related molecules identified in the screen, econazole nitrate and miconazole nitrate, were followed in validation and mechanistic studies. Both compounds reduced lysis of choroidal ECs treated with complement-intact serum, across a range of doses from 1 to 100 µM. Cell rescue was confirmed in mouse primary choroidal ECs. Both exosome release and cell surface roughness (assessed using a Holomonitor system) were reduced by drug pretreatment in RF/6A cells, whereas endosome formation increased with both drugs, consistent with imidazole-mediated alterations of cell surface dynamics. The results in the current study provide further proof of principle that small molecules can protect choroidal ECs from MAC-induced cell death and suggest that FDA approved compounds may be beneficial in reducing vascular loss and progression of AMD.
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Affiliation(s)
- Shemin Zeng
- The University of Iowa Institute for Vision Research, Iowa City, USA.,University of Iowa Department of Ophthalmology and Visual Sciences, Iowa City, USA
| | - Kuo-Kuang Wen
- University of Iowa Department of Biochemistry, Iowa City, USA
| | - Grefachew Workalemahu
- The University of Iowa Institute for Vision Research, Iowa City, USA.,University of Iowa Department of Ophthalmology and Visual Sciences, Iowa City, USA
| | - Elliott H Sohn
- The University of Iowa Institute for Vision Research, Iowa City, USA.,University of Iowa Department of Ophthalmology and Visual Sciences, Iowa City, USA
| | - Meng Wu
- University of Iowa Department of Biochemistry, Iowa City, USA
| | - Kathleen R Chirco
- The University of Iowa Institute for Vision Research, Iowa City, USA.,University of Iowa Department of Ophthalmology and Visual Sciences, Iowa City, USA
| | - Miles J Flamme-Wiese
- The University of Iowa Institute for Vision Research, Iowa City, USA.,University of Iowa Department of Ophthalmology and Visual Sciences, Iowa City, USA
| | - Xiuying Liu
- The University of Iowa Institute for Vision Research, Iowa City, USA.,University of Iowa Department of Ophthalmology and Visual Sciences, Iowa City, USA
| | - Edwin M Stone
- The University of Iowa Institute for Vision Research, Iowa City, USA.,University of Iowa Department of Ophthalmology and Visual Sciences, Iowa City, USA
| | - Budd A Tucker
- The University of Iowa Institute for Vision Research, Iowa City, USA.,University of Iowa Department of Ophthalmology and Visual Sciences, Iowa City, USA
| | - Robert F Mullins
- The University of Iowa Institute for Vision Research, Iowa City, USA. .,University of Iowa Department of Ophthalmology and Visual Sciences, Iowa City, USA.
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7
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The AFF-1 exoplasmic fusogen is required for endocytic scission and seamless tube elongation. Nat Commun 2018; 9:1741. [PMID: 29717108 PMCID: PMC5931541 DOI: 10.1038/s41467-018-04091-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 04/03/2018] [Indexed: 12/28/2022] Open
Abstract
Many membranes must merge during cellular trafficking, but fusion and fission events initiating at exoplasmic (non-cytosolic) membrane surfaces are not well understood. Here we show that the C. elegans cell-cell fusogen anchor-cell fusion failure 1 (AFF-1) is required for membrane trafficking events during development of a seamless unicellular tube. EGF-Ras-ERK signaling upregulates AFF-1 expression in the excretory duct tube to promote tube auto-fusion and subsequent lumen elongation. AFF-1 is required for scission of basal endocytic compartments and for apically directed exocytosis to extend the apical membrane. Lumen elongation also requires the transcytosis factor Rab11, but occurs independently of dynamin and clathrin. These results support a transcytosis model of seamless tube lumen growth and show that cell-cell fusogens also can play roles in intracellular membrane trafficking events.
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8
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Garcia-Castillo MD, Chinnapen DJF, Lencer WI. Membrane Transport across Polarized Epithelia. Cold Spring Harb Perspect Biol 2017; 9:cshperspect.a027912. [PMID: 28213463 DOI: 10.1101/cshperspect.a027912] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Polarized epithelial cells line diverse surfaces throughout the body forming selective barriers between the external environment and the internal milieu. To cross these epithelial barriers, large solutes and other cargoes must undergo transcytosis, an endocytic pathway unique to polarized cell types, and significant for the development of cell polarity, uptake of viral and bacterial pathogens, transepithelial signaling, and immunoglobulin transport. Here, we review recent advances in our knowledge of the transcytotic pathway for proteins and lipids. We also discuss briefly the promise of harnessing the molecules that undergo transcytosis as vehicles for clinical applications in drug delivery.
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Affiliation(s)
| | - Daniel J-F Chinnapen
- Division of Gastroenterology, Boston Children's Hospital, Boston, Massachusetts 02155.,Department of Pediatrics, Harvard Medical School, Boston, Massachusetts 02155.,Department of Pediatrics, Harvard Digestive Diseases Center, Boston, Massachusetts 02155
| | - Wayne I Lencer
- Division of Gastroenterology, Boston Children's Hospital, Boston, Massachusetts 02155.,Department of Pediatrics, Harvard Medical School, Boston, Massachusetts 02155.,Department of Pediatrics, Harvard Digestive Diseases Center, Boston, Massachusetts 02155
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9
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Zhao Z, Sagare AP, Ma Q, Halliday MR, Kong P, Kisler K, Winkler EA, Ramanathan A, Kanekiyo T, Bu G, Owens NC, Rege SV, Si G, Ahuja A, Zhu D, Miller CA, Schneider JA, Maeda M, Maeda T, Sugawara T, Ichida JK, Zlokovic BV. Central role for PICALM in amyloid-β blood-brain barrier transcytosis and clearance. Nat Neurosci 2015; 18:978-87. [PMID: 26005850 PMCID: PMC4482781 DOI: 10.1038/nn.4025] [Citation(s) in RCA: 305] [Impact Index Per Article: 33.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Accepted: 04/21/2015] [Indexed: 12/11/2022]
Abstract
PICALM is a highly validated genetic risk factor for Alzheimer's disease (AD). We found that reduced expression of PICALM in AD and murine brain endothelium correlated with amyloid-β (Aβ) pathology and cognitive impairment. Moreover, Picalm deficiency diminished Aβ clearance across the murine blood-brain barrier (BBB) and accelerated Aβ pathology in a manner that was reversible by endothelial PICALM re-expression. Using human brain endothelial monolayers, we found that PICALM regulated PICALM/clathrin-dependent internalization of Aβ bound to the low density lipoprotein receptor related protein-1, a key Aβ clearance receptor, and guided Aβ trafficking to Rab5 and Rab11, leading to Aβ endothelial transcytosis and clearance. PICALM levels and Aβ clearance were reduced in AD-derived endothelial monolayers, which was reversible by adenoviral-mediated PICALM transfer. Inducible pluripotent stem cell-derived human endothelial cells carrying the rs3851179 protective allele exhibited higher PICALM levels and enhanced Aβ clearance. Thus, PICALM regulates Aβ BBB transcytosis and clearance, which has implications for Aβ brain homeostasis and clearance therapy.
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Affiliation(s)
- Zhen Zhao
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Abhay P. Sagare
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Qingyi Ma
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Matthew R. Halliday
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Pan Kong
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Kassandra Kisler
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Ethan A. Winkler
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
- Department of Neurological Surgery, University of California San Francisco, San Francisco, CA 94143, USA
| | - Anita Ramanathan
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Takahisa Kanekiyo
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Guojun Bu
- Department of Neuroscience, Mayo Clinic, Jacksonville, FL 32224, USA
| | - Nelly Chuqui Owens
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Sanket V. Rege
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Gabriel Si
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Ashim Ahuja
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Donghui Zhu
- Department of Chemical, Biological and Bio–Engineering, North Carolina Agricultural and Technical State University, Greensboro, NC 27411, USA
| | - Carol A. Miller
- Department of Pathology, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
| | - Julie A. Schneider
- Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL 60612, USA
| | - Manami Maeda
- Division of Hematopoietic Stem Cell and Leukemia Research, Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA
- Division of Hematology, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Takahiro Maeda
- Division of Hematopoietic Stem Cell and Leukemia Research, Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA
- Division of Hematology, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Tohru Sugawara
- Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, and Department of Stem Cell Biology and Regenerative Medicine, University of Southern California, 1425 San Pablo Street, BCC 307, Los Angeles, CA 90089, USA
| | - Justin K. Ichida
- Eli and Edythe Broad Center for Regenerative Medicine and Stem Cell Research, and Department of Stem Cell Biology and Regenerative Medicine, University of Southern California, 1425 San Pablo Street, BCC 307, Los Angeles, CA 90089, USA
| | - Berislav V. Zlokovic
- Zilkha Neurogenetic Institute and Department of Physiology and Biophysics, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA
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10
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Hsueh PY, Edman MC, Sun G, Shi P, Xu S, Lin YA, Cui H, Hamm-Alvarez SF, MacKay JA. Tear-mediated delivery of nanoparticles through transcytosis of the lacrimal gland. J Control Release 2015; 208:2-13. [PMID: 25523518 PMCID: PMC4456098 DOI: 10.1016/j.jconrel.2014.12.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 12/06/2014] [Accepted: 12/14/2014] [Indexed: 11/16/2022]
Abstract
Rapid clearance from the tears presents a formidable obstacle to the delivery of peptide drugs to the eye surface. This impedes therapies for ocular infections, wound healing, and dry-eye disease that affect the vision of millions worldwide. To overcome this challenge, this manuscript explores a novel strategy to reach the ocular surface via receptor-mediated transcytosis across the lacrimal gland (LG), which produces the bulk of human tears. The LG abundantly expresses the coxsackievirus and adenovirus receptor (CAR); furthermore, we recently reported a peptide-based nanoparticle (KSI) that targets CAR on liver cells. This manuscript reports the unexpected finding that KSI both targets and transcytoses into the LG acinar lumen, which drains to tear ducts. When followed using ex vivo live cell imaging KSI rapidly accumulates in lumen formed by LG acinar cells. LG transduction with a myosin Vb tail, which is dominant negative towards transcytosis, inhibits lumenal accumulation. Transcytosis of KSI was confirmed in vivo by confocal and TEM imaging of LG tissue following administration of KSI nanoparticles. These findings suggest that it is possible to target nanomaterials to the tears by targeting certain receptors on the LG. This design strategy represents a new opportunity to overcome barriers to ocular delivery.
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Affiliation(s)
- Pang-Yu Hsueh
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90033, USA
| | - Maria C Edman
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90033, USA
| | - Guoyong Sun
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90033, USA
| | - Pu Shi
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90033, USA
| | - Shi Xu
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90033, USA
| | - Yi-An Lin
- Department of Chemical and Biomolecular Engineering, John Hopkins University, Baltimore, MD 21218, USA
| | - Honggang Cui
- Department of Chemical and Biomolecular Engineering, John Hopkins University, Baltimore, MD 21218, USA
| | - Sarah F Hamm-Alvarez
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90033, USA
| | - J Andrew MacKay
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California, Los Angeles, CA 90033, USA; Department of Biomedical Engineering, University of Southern California, Los Angeles, CA 90089, USA.
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11
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Yu S, Gao N. Compartmentalizing intestinal epithelial cell toll-like receptors for immune surveillance. Cell Mol Life Sci 2015; 72:3343-53. [PMID: 26001904 DOI: 10.1007/s00018-015-1931-1] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Revised: 05/13/2015] [Accepted: 05/18/2015] [Indexed: 02/08/2023]
Abstract
Toll-like receptors (TLRs) are membrane-bound microbial sensors that mediate important host-to-microbe responses. Cell biology aspects of TLR function have been intensively studied in professional immune cells, in particular the macrophages and dendritic cells, but not well explored in other specialized epithelial cell types. The adult intestinal epithelial cells are in close contact with trillions of enteric microbes and engage in lifelong immune surveillance. Mature intestinal epithelial cells, in contrast to immune cells, are highly polarized. Recent studies suggest that distinct mechanisms may govern TLR traffic and compartmentalization in these specialized epithelial cells to establish and maintain precise signaling of individual TLRs. We, using immune cells as references, discuss here the shared and/or unique molecular machineries used by intestinal epithelial cells to control TLR transport, localization, processing, activation, and signaling. A better understanding of these mechanisms will certainly generate important insights into both the mechanism and potential intervention of leading digestive disorders, in particular inflammatory bowel diseases.
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Affiliation(s)
- Shiyan Yu
- Department of Biological Sciences, Rutgers University, Room 206, 195 University Ave., Newark, NJ, 07102, USA
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12
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Gallo LI, Liao Y, Ruiz WG, Clayton DR, Li M, Liu YJ, Jiang Y, Fukuda M, Apodaca G, Yin XM. TBC1D9B functions as a GTPase-activating protein for Rab11a in polarized MDCK cells. Mol Biol Cell 2014; 25:3779-97. [PMID: 25232007 PMCID: PMC4230784 DOI: 10.1091/mbc.e13-10-0604] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Rab11a is a key modulator of vesicular trafficking processes, but there is limited information about the GEFs and GAPs that regulate its GTP-GDP cycle. TBC1D9B is identified as a Rab11a GAP in MDCK cells, where it regulates the Rab11a-dependent basolateral-to-apical transcytotic pathway. Rab11a is a key modulator of vesicular trafficking processes, but there is limited information about the guanine nucleotide-exchange factors and GTPase-activating proteins (GAPs) that regulate its GTP-GDP cycle. We observed that in the presence of Mg2+ (2.5 mM), TBC1D9B interacted via its Tre2-Bub2-Cdc16 (TBC) domain with Rab11a, Rab11b, and Rab4a in a nucleotide-dependent manner. However, only Rab11a was a substrate for TBC1D9B-stimulated GTP hydrolysis. At limiting Mg2+ concentrations (<0.5 mM), Rab8a was an additional substrate for this GAP. In polarized Madin–Darby canine kidney cells, endogenous TBC1D9B colocalized with Rab11a-positive recycling endosomes but less so with EEA1-positive early endosomes, transferrin-positive recycling endosomes, or late endosomes. Overexpression of TBC1D9B, but not an inactive mutant, decreased the rate of basolateral-to-apical IgA transcytosis—a Rab11a-dependent pathway—and shRNA-mediated depletion of TBC1D9B increased the rate of this process. In contrast, TBC1D9B had no effect on two Rab11a-independent pathways—basolateral recycling of the transferrin receptor or degradation of the epidermal growth factor receptor. Finally, expression of TBC1D9B decreased the amount of active Rab11a in the cell and concomitantly disrupted the interaction between Rab11a and its effector, Sec15A. We conclude that TBC1D9B is a Rab11a GAP that regulates basolateral-to-apical transcytosis in polarized MDCK cells.
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Affiliation(s)
- Luciana I Gallo
- Departments of Medicine, University of Pittsburgh, Pittsburgh, PA 15261
| | - Yong Liao
- Pathology, University of Pittsburgh, Pittsburgh, PA 15261
| | - Wily G Ruiz
- Departments of Medicine, University of Pittsburgh, Pittsburgh, PA 15261
| | - Dennis R Clayton
- Departments of Medicine, University of Pittsburgh, Pittsburgh, PA 15261
| | - Min Li
- Pathology, University of Pittsburgh, Pittsburgh, PA 15261 Department of Pathology and Laboratory Medicine, Indiana University, Indianapolis, IN 46202
| | - Yong-Jian Liu
- Neurobiology, University of Pittsburgh, Pittsburgh, PA 15261
| | - Yu Jiang
- Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA 15261
| | - Mitsunori Fukuda
- Department of Developmental Biology and Neurosciences, Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi 980-8578, Japan
| | - Gerard Apodaca
- Departments of Medicine, University of Pittsburgh, Pittsburgh, PA 15261 Cell Biology, University of Pittsburgh, Pittsburgh, PA 15261
| | - Xiao-Ming Yin
- Pathology, University of Pittsburgh, Pittsburgh, PA 15261 Department of Pathology and Laboratory Medicine, Indiana University, Indianapolis, IN 46202
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13
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van der Velde KJ, Dhekne HS, Swertz MA, Sirigu S, Ropars V, Vinke PC, Rengaw T, van den Akker PC, Rings EHHM, Houdusse A, van Ijzendoorn SCD. An overview and online registry of microvillus inclusion disease patients and their MYO5B mutations. Hum Mutat 2013; 34:1597-605. [PMID: 24014347 DOI: 10.1002/humu.22440] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2013] [Accepted: 08/29/2013] [Indexed: 01/26/2023]
Abstract
Microvillus inclusion disease (MVID) is one of the most severe congenital intestinal disorders and is characterized by neonatal secretory diarrhea and the inability to absorb nutrients from the intestinal lumen. MVID is associated with patient-, family-, and ancestry-unique mutations in the MYO5B gene, encoding the actin-based motor protein myosin Vb. Here, we review the MYO5B gene and all currently known MYO5B mutations and for the first time methodologically categorize these with regard to functional protein domains and recurrence in MYO7A associated with Usher syndrome and other myosins. We also review animal models for MVID and the latest data on functional studies related to the myosin Vb protein. To congregate existing and future information on MVID geno-/phenotypes and facilitate its quick and easy sharing among clinicians and researchers, we have constructed an online MOLGENIS-based international patient registry (www.MVID-central.org). This easily accessible database currently contains detailed information of 137 MVID patients together with reported clinical/phenotypic details and 41 unique MYO5B mutations, of which several unpublished. The future expansion and prospective nature of this registry is expected to improve disease diagnosis, prognosis, and genetic counseling.
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Affiliation(s)
- K Joeri van der Velde
- Genomics Coordination Center, Department of Genetics, University Medical Center Groningen, University of Groningen, The Netherlands
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14
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Xu S, Ma L, Evans E, Okamoto CT, Hamm-Alvarez SF. Polymeric immunoglobulin receptor traffics through two distinct apically targeted pathways in primary lacrimal gland acinar cells. J Cell Sci 2013; 126:2704-17. [PMID: 23606742 DOI: 10.1242/jcs.122242] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The polymeric immunoglobulin receptor (pIgR) mediates transcytosis of dimeric immunoglobulin A (dIgA) and its release into mucosal secretions. The present study reveals the complexity of the trafficking of pIgR to the apical plasma membrane in epithelial cells with exocrine secretory functions; in rabbit lacrimal gland acinar cells (LGACs), trafficking of pIgR involves both the transcytotic pathway and one arm of the regulated secretory pathway. By specifically tracking pIgR endocytosed from the basolateral membrane, we show here that the Rab11a-regulated transcytotic pathway mediates the basal-to-apical transport of pIgR, and that pIgR sorted into the transcytotic pathway does not access the regulated secretory pathway. However, previous work in LGACs expanded in the present study has shown that some pIgR is localized to Rab3D-enriched mature secretory vesicles (SVs). Myosin Vb and myosin Vc motors modulate release of proteins from the Rab11a-regulated transcytotic pathway and the Rab3D-enriched secretory pathway in LGACs, respectively. Confocal fluorescence microscopy and biochemical assays showed that inhibition of myosin Vb and myosin Vc activity by overexpression of their dominant-negative mutants each significantly but differentially impaired aspects of apically targeted pIgR trafficking and secretory component release, suggesting that these motors function to regulate pIgR trafficking in both the transcytotic and exocytotic pathways. Intriguingly, a second mature SV population enriched in Rab27b was devoid of pIgR cargo, suggesting the specialization of Rab3D-enriched mature SVs to carry a particular subset of cargo proteins from the trans-Golgi network to the apical plasma membrane.
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Affiliation(s)
- Shi Xu
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90033, USA
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15
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Khandelwal P, Prakasam HS, Clayton DR, Ruiz WG, Gallo LI, van Roekel D, Lukianov S, Peränen J, Goldenring JR, Apodaca G. A Rab11a-Rab8a-Myo5B network promotes stretch-regulated exocytosis in bladder umbrella cells. Mol Biol Cell 2013; 24:1007-19. [PMID: 23389633 PMCID: PMC3608489 DOI: 10.1091/mbc.e12-08-0568] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2012] [Revised: 01/29/2013] [Accepted: 01/30/2013] [Indexed: 12/03/2022] Open
Abstract
Multiple Rabs are associated with secretory granules/vesicles, but how these GTPases are coordinated to promote regulated exocytosis is not well understood. In bladder umbrella cells a subapical pool of discoidal/fusiform-shaped vesicles (DFVs) undergoes Rab11a-dependent regulated exocytosis in response to bladder filling. We show that Rab11a-associated vesicles are enmeshed in an apical cytokeratin meshwork and that Rab11a likely acts upstream of Rab8a to promote exocytosis. Surprisingly, expression of Rabin8, a previously described Rab11a effector and guanine nucleotide exchange factor for Rab8, stimulates stretch-induced exocytosis in a manner that is independent of its catalytic activity. Additional studies demonstrate that the unconventional motor protein myosin5B motor (Myo5B) works in association with the Rab8a-Rab11a module to promote exocytosis, possibly by ensuring transit of DFVs through a subapical, cortical actin cytoskeleton before fusion. Our results indicate that Rab11a, Rab8a, and Myo5B function as part of a network to promote stretch-induced exocytosis, and we predict that similarly organized Rab networks will be common to other regulated secretory pathways.
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Affiliation(s)
- Puneet Khandelwal
- Departments of Medicine, University of Pittsburgh, Pittsburgh, PA 15261
| | | | - Dennis R. Clayton
- Departments of Medicine, University of Pittsburgh, Pittsburgh, PA 15261
| | - Wily G. Ruiz
- Departments of Medicine, University of Pittsburgh, Pittsburgh, PA 15261
| | - Luciana I. Gallo
- Departments of Medicine, University of Pittsburgh, Pittsburgh, PA 15261
| | - Daniel van Roekel
- Departments of Medicine, University of Pittsburgh, Pittsburgh, PA 15261
| | - Stefan Lukianov
- Departments of Medicine, University of Pittsburgh, Pittsburgh, PA 15261
| | - Johan Peränen
- Institute of Biotechnology, University of Helsinki, 00014 Helsinki, Finland
| | - James R. Goldenring
- Department of Surgery and Epithelial Biology Center, Vanderbilt University, Nashville, TN 37232
| | - Gerard Apodaca
- Departments of Medicine, University of Pittsburgh, Pittsburgh, PA 15261
- Cell Biology, University of Pittsburgh, Pittsburgh, PA 15261
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16
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Mirror-symmetric microtubule assembly and cell interactions drive lumen formation in the zebrafish neural rod. EMBO J 2012; 32:30-44. [PMID: 23202854 PMCID: PMC3545300 DOI: 10.1038/emboj.2012.305] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Accepted: 10/30/2012] [Indexed: 02/06/2023] Open
Abstract
By analysing the cellular and subcellular events that occur in the centre of the developing zebrafish neural rod, we have uncovered a novel mechanism of cell polarisation during lumen formation. Cells from each side of the neural rod interdigitate across the tissue midline. This is necessary for localisation of apical junctional proteins to the region where cells intersect the tissue midline. Cells assemble a mirror-symmetric microtubule cytoskeleton around the tissue midline, which is necessary for the trafficking of proteins required for normal lumen formation, such as partitioning defective 3 and Rab11a to this point. This occurs in advance and is independent of the midline cell division that has been shown to have a powerful role in lumen organisation. To our knowledge, this is the first example of the initiation of apical polarisation part way along the length of a cell, rather than at a cell extremity. Although the midline division is not necessary for apical polarisation, it confers a morphogenetic advantage by efficiently eliminating cellular processes that would otherwise bridge the developing lumen.
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17
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Young JS, Takai Y, Kojic KL, Vogl AW. Internalization of adhesion junction proteins and their association with recycling endosome marker proteins in rat seminiferous epithelium. Reproduction 2011; 143:347-57. [PMID: 22157319 DOI: 10.1530/rep-11-0317] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Tubulobulbar complexes (TBCs) are elaborate cytoskeleton-related structures that are formed in association with intercellular junctions in the seminiferous epithelium. They consist of a cylindrical double-membrane core composed of the plasma membranes of the two attached cells, cuffed by a dendritic network of actin filaments. TBCs are proposed to be subcellular machines that internalize intercellular junctions during the extensive junction remodeling that occurs during spermatogenesis. At the apical sites of attachment between Sertoli cells and spermatids, junction disassembly is part of the sperm release mechanism. In this study, we used immunological probes to explore junction internalization and recycling at apical TBCs in the rat seminiferous epithelium. We demonstrate that β1-integrin and nectin 2 were concentrated at the ends of TBCs and for the first time show that the early endosome marker RAB5A was also distinctly localized at the ends of TBCs that appear to be the 'bulbar' regions of the complexes. Significantly, we also demonstrate that the 'long-loop' recycling endosome marker RAB11A was co-distributed with nectin 2 at junctions with early spermatids deeper in the epithelium. Our results are consistent with the hypothesis that TBCs associated with late spermatids internalize adhesion junctions and also indicate that some of the internalized junction proteins may be recycled to form junctions with the next generation of spermatids.
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Affiliation(s)
- J'Nelle S Young
- Department of Cellular and Physiological Sciences, Life Sciences Centre, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, British Columbia, Canada V6T 1Z3
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