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Prasad A, Qamri Z, Wu J, Ganju RK. Slit-2/Robo-1 modulates the CXCL12/CXCR4-induced chemotaxis of T cells. J Leukoc Biol 2007; 82:465-76. [PMID: 17565045 PMCID: PMC2286829 DOI: 10.1189/jlb.1106678] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Slit, which mediates its function by binding to the Roundabout (Robo) receptor, has been shown to regulate neuronal, dendritic, and leukocyte migration. However, the molecular mechanism by which the Slit/Robo complex inhibits the migration of cells is not well defined. Here, we showed that Slit-2 can inhibit the CXCL12-induced chemotaxis and transendothelial migration of T cells and monocytes. We observed that CXCR4 associates with Robo-1 and that Slit-2 treatment enhances this association with the Robo-1 receptor. Robo-1 is a single-pass transmembrane receptor whose intracellular region contains four conserved motifs designated as CC0, CC1, CC2, and CC3. Structural and functional analyses of Robo receptors revealed that interaction of the CC3 motif with the CXCR4 receptor may regulate the CXCL12-induced chemotaxis of T cells. We further characterized Slit-2-mediated inhibition of the CXCL12/CXCR4 chemotactic pathway and found that Slit-2 can block the CXCL12-induced activation of the Src and Lck kinases but not Lyn kinase. Although Slit-2 did not inhibit the CXCL12-induced activation of MAPKs, it did inhibit the Akt phosphorylation and Rac activation induced by this chemokine. Altogether, our studies indicate a novel mechanism by which the Slit/Robo complex may inhibit the CXCR4/CXCL12-mediated chemotaxis of T cells.
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MESH Headings
- Blotting, Western
- Cell Adhesion/physiology
- Cell Movement/physiology
- Cell Survival
- Cells, Cultured
- Chemokine CXCL12
- Chemokines, CXC/metabolism
- Chemotaxis, Leukocyte/drug effects
- Endothelium, Vascular/cytology
- Endothelium, Vascular/drug effects
- Endothelium, Vascular/metabolism
- Flow Cytometry
- Humans
- Immunoprecipitation
- Intercellular Signaling Peptides and Proteins/pharmacology
- Jurkat Cells/metabolism
- Mitogen-Activated Protein Kinases/metabolism
- Monocytes/physiology
- Nerve Tissue Proteins/pharmacology
- Phosphorylation
- Proto-Oncogene Proteins c-akt/metabolism
- RNA, Small Interfering/pharmacology
- Receptors, CXCR4/metabolism
- Receptors, Immunologic
- Signal Transduction
- T-Lymphocytes/physiology
- cdc42 GTP-Binding Protein/metabolism
- Roundabout Proteins
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Affiliation(s)
- Anil Prasad
- Division of Experimental Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Zahida Qamri
- Division of Experimental Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Jane Wu
- Northwestern University Feinberg Medical School, Robert H. Laurie Comprehensive Cancer Center, Center for Genetic Medicine, Chicago, Illinois, USA
| | - Ramesh K. Ganju
- Division of Experimental Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
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Cebrià F, Guo T, Jopek J, Newmark PA. Regeneration and maintenance of the planarian midline is regulated by a slit orthologue. Dev Biol 2007; 307:394-406. [PMID: 17553481 PMCID: PMC2148499 DOI: 10.1016/j.ydbio.2007.05.006] [Citation(s) in RCA: 90] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2007] [Revised: 05/02/2007] [Accepted: 05/04/2007] [Indexed: 01/06/2023]
Abstract
Several families of evolutionarily conserved axon guidance cues orchestrate the precise wiring of the nervous system during embryonic development. The remarkable plasticity of freshwater planarians provides the opportunity to study these molecules in the context of neural regeneration and maintenance. Here we characterize a homologue of the Slit family of guidance cues from the planarian Schmidtea mediterranea. Smed-slit is expressed along the planarian midline, in both dorsal and ventral domains. RNA interference (RNAi) targeting Smed-slit results in the collapse of many newly regenerated tissues at the midline; these include the cephalic ganglia, ventral nerve cords, photoreceptors, and the posterior digestive system. Surprisingly, Smed-slit RNAi knockdown animals also develop morphologically distinguishable, ectopic neural structures near the midline in uninjured regions of intact and regenerating planarians. These results suggest that Smed-slit acts not only as a repulsive cue required for proper midline formation during regeneration but that it may also act to regulate the behavior of neural precursors at the midline in intact planarians.
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Affiliation(s)
- Francesc Cebrià
- Department of Cell and Developmental Biology, University of Illinois at Urbana-Champaign, B107 Chemical and Life Sciences Laboratory, 601 South Goodwin Avenue, Urbana, IL 61801, USA
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Tanno T, Fujiwara A, Sakaguchi K, Tanaka K, Takenaka S, Tsuyama S. Slit3 regulates cell motility through Rac/Cdc42 activation in lipopolysaccharide-stimulated macrophages. FEBS Lett 2007; 581:1022-6. [PMID: 17306799 DOI: 10.1016/j.febslet.2007.02.001] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2006] [Revised: 01/19/2007] [Accepted: 02/03/2007] [Indexed: 11/16/2022]
Abstract
Three slit genes, slit1 to slit3, have been cloned to date. Slit1 and slit2 act as chemorepellent factors for axon guidance. Slit3 is involved in the formation of the diaphragm and kidney during embryogenesis. However, its molecular function remains unclear. We found that slit3 expression was induced by lipopolysaccharide (LPS)-stimulation in macrophages and that it was localized in the mitochondria and along the plasma membrane. Silencing of slit3 expression by RNA interference reduced cell motility and Rac/Cdc42 activation. These results suggest that slit3 functions as an intracellular signaling molecule for cell motility as part of the LPS-induced signaling cascade.
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Affiliation(s)
- Toshihiko Tanno
- Department of Veterinary Science, Graduate School of Life and Environmental Sciences, Osaka Prefecture University, Sakai, Osaka 599-8531, Japan
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54
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Caruana G, Cullen-McEwen L, Nelson AL, Kostoulias X, Woods K, Gardiner B, Davis MJ, Taylor DF, Teasdale RD, Grimmond SM, Little MH, Bertram JF. Spatial gene expression in the T-stage mouse metanephros. Gene Expr Patterns 2006; 6:807-25. [PMID: 16545622 DOI: 10.1016/j.modgep.2006.02.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2005] [Revised: 01/31/2006] [Accepted: 02/03/2006] [Indexed: 01/28/2023]
Abstract
The E11.5 mouse metanephros is comprised of a T-stage ureteric epithelial tubule sub-divided into tip and trunk cells surrounded by metanephric mesenchyme (MM). Tip cells are induced to undergo branching morphogenesis by the MM. In contrast, signals within the mesenchyme surrounding the trunk prevent ectopic branching of this region. In order to identify novel genes involved in the molecular regulation of branching morphogenesis we compared the gene expression profiles of isolated tip, trunk and MM cells using Compugen mouse long oligo microarrays. We identified genes enriched in the tip epithelium, sim-1, Arg2, Tacstd1, Crlf-1 and BMP7; genes enriched in the trunk epithelium, Innp1, Itm2b, Mkrn1, SPARC, Emu2 and Gsta3 and genes spatially restricted to the mesenchyme surrounding the trunk, CSPG2 and CV-2, with overlapping and complimentary expression to BMP4, respectively. This study has identified genes spatially expressed in regions of the developing kidney involved in branching morphogenesis, nephrogenesis and the development of the collecting duct system, calyces, renal pelvis and ureter.
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Affiliation(s)
- Georgina Caruana
- Department of Anatomy and Cell Biology, Monash University, Clayton, Vic., Australia.
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55
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Molendi-Coste O, Grumolato L, Laborie C, Lesage J, Maubert E, Ghzili H, Vaudry H, Anouar Y, Breton C, Vieau D. Maternal perinatal undernutrition alters neuronal and neuroendocrine differentiation in the rat adrenal medulla at weaning. Endocrinology 2006; 147:3050-9. [PMID: 16497807 DOI: 10.1210/en.2005-1331] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Epidemiological studies suggest that chronic adult diseases, such as type 2 diabetes and hypertension, can be programmed during fetal and early postnatal life. The nervous system regions governing vegetative functions and the hypothalamic-pituitary-adrenal axis are particularly sensitive to the perinatal nutritional status. Despite recent reports demonstrating that the activity of the sympathoadrenal system can be altered by early life events, the effects of maternal nutrient restriction on the adrenal medulla remain unknown. Using a rat model of maternal perinatal 50% food restriction (FR50) from the second week of gestation until weaning, immunohistochemical experiments revealed alterations in chromaffin cell aggregation and in nerve fiber fasciculation in the adrenal medulla of FR50 pups. These morphological changes were associated with enhanced circulating levels of catecholamines after decapitation (epinephrine by 55% and norepinephrine by 41%). Using macroarrays, we identified several genes whose expression was affected by maternal nutrient restriction. Semiquantitative RT-PCR confirmed the overexpression of four genes involved in neuroendocrine differentiation and neuronal plasticity (chromogranin B, growth-associated protein 43, neurofilament 3, and Slit2) in the adrenal glands of FR50 rats. Using in situ hybridization, we showed that these genes are solely expressed in the adrenal medulla. Together, our results suggest that perinatal maternal undernutrition markedly alters the differentiation of the adrenal medulla during postnatal life, resulting in enhanced activity of chromaffin cells at weaning. These alterations may persist in adulthood and participate to the programming of chronic adult diseases.
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Affiliation(s)
- Olivier Molendi-Coste
- Unité Propre de Recherche et de l'Enseignement Supérieur Equipe Associée 2701, Laboratoire de Neuroendocrinologie du Développement, Université des Sciences et Technologies de Lille, 59655 Villeneuve d'Ascq Cedex, France
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56
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Dalkic E, Kuscu C, Sucularli C, Aydin IT, Akcali KC, Konu O. Alternatively spliced Robo2 isoforms in zebrafish and rat. Dev Genes Evol 2006; 216:555-63. [PMID: 16625395 DOI: 10.1007/s00427-006-0070-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2005] [Accepted: 03/13/2006] [Indexed: 11/27/2022]
Abstract
Robo2, a member of the robo gene family, functions as a repulsive axon guidance receptor as well as a regulator of cell migration and tissue morphogenesis in different taxa. In this study, a novel isoform of the zebrafish robo2 (robo2_tv2), which included an otherwise alternatively spliced exon (CAE), has been characterized. Robo2_tv2 is expressed differentially in most non-neuronal tissues of adult zebrafish whereas robo2_tv1 expression to a great extent is restricted to the brain and eye. In zebrafish, robo2_tv2 exhibits a very-low-level basal expression starting from 1 day post fertilization until the mid-larval stages, at which time its expression increases dramatically and could be detected throughout adulthood. Our findings demonstrate that the amino acid sequence coded by CAE of the robo2 gene is highly conserved between zebrafish and mammals, and also contains conserved motifs shared with robo1 and robo4 but not with robo3. Furthermore, we provide an account of differential transcription of the CAE homolog in various tissues of the adult rat. These results suggest that the alternatively spliced robo2 isoforms may exhibit tissue specificity.
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Affiliation(s)
- Ertugrul Dalkic
- Department of Molecular Biology and Genetics, Bilkent University, 06800, Ankara, Turkey
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57
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Schwab K, Hartman HA, Liang HC, Aronow BJ, Patterson LT, Potter SS. Comprehensive microarray analysis of Hoxa11/Hoxd11 mutant kidney development. Dev Biol 2006; 293:540-54. [PMID: 16581055 DOI: 10.1016/j.ydbio.2006.02.023] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2005] [Revised: 02/02/2006] [Accepted: 02/16/2006] [Indexed: 01/10/2023]
Abstract
The Hox11 paralogous genes play critical roles in kidney development. They are expressed in the early metanephric mesenchyme and are required for the induction of ureteric bud formation and its subsequent branching morphogenesis. They are also required for the normal nephrogenesis response of the metanephric mesenchyme to inductive signals from the ureteric bud. In this report, we use microarrays to perform a comprehensive gene expression analysis of the Hoxa11/Hoxd11 mutant kidney phenotype. We examined E11.5, E12.5, E13.5 and E16.5 developmental time points. A novel high throughput strategy for validation of microarray data is described, using additional biological replicates and an independent microarray platform. The results identified 13 genes with greater than 3-fold change in expression in early mutant kidneys, including Hoxa11s, GATA6, TGFbeta2, chemokine ligand 12, angiotensin receptor like 1, cytochrome P450, cadherin5, and Lymphocyte antigen 6 complex, Iroquois 3, EST A930038C07Rik, Meox2, Prkcn, and Slc40a1. Of interest, many of these genes, and others showing lower fold expression changes, have been connected to processes that make sense in terms of the mutant phenotype, including TGFbeta signaling, iron transport, protein kinase C function, growth arrest and GDNF regulation. These results identify the multiple molecular pathways downstream of Hox11 function in the developing kidney.
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Affiliation(s)
- Kristopher Schwab
- Division of Developmental Biology, Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229, USA
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58
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Klagsbrun M, Eichmann A. A role for axon guidance receptors and ligands in blood vessel development and tumor angiogenesis. Cytokine Growth Factor Rev 2005; 16:535-48. [PMID: 15979925 DOI: 10.1016/j.cytogfr.2005.05.002] [Citation(s) in RCA: 173] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Nerves and blood vessels resemble each other in their ability to form branching networks. They are in close proximity suggesting possible molecular interactions. The patterning of nerves and blood vessels are not random but are regulated by attractive and repulsive cues. Four major neuronal guidance factors that are sensed by growth cones have been identified, Semaphorin, Ephrin, Slit and Netrin, and their cognate receptors, neuropilin, Eph, roundabouts (Robo) and uncoordinated-5 (UNC5). Unexpectedly, these ligand/receptor pairs also regulate developmental and tumor angiogenesis. Together, there is strong evidence that development of the nervous and vascular systems are regulated by common cues.
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Affiliation(s)
- Michael Klagsbrun
- Vascular Biology Program, Department of Surgery, Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.
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59
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Eichmann A, Makinen T, Alitalo K. Neural guidance molecules regulate vascular remodeling and vessel navigation. Genes Dev 2005; 19:1013-21. [PMID: 15879551 DOI: 10.1101/gad.1305405] [Citation(s) in RCA: 187] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The development of the embryonic blood vascular and lymphatic systems requires the coordinated action of several transcription factors and growth factors that target endothelial and periendothelial cells. However, according to recent studies, the precise "wiring" of the vascular system does not occur without an ordered series of guidance decisions involving several molecules initially discovered for axons in the nervous system, including ephrins, netrins, slits, and semaphorins. Here, we summarize the new advances in our understanding of the roles of these axonal pathfinding molecules in vascular remodeling and vessel guidance, indicating that neuronal axons and vessel sprouts use common molecular mechanisms for navigation in the body.
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Affiliation(s)
- Anne Eichmann
- Institut National de la Santé et de la Recherche Médicale U36, Collège de France, 75005 Paris, France.
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60
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Abstract
The human brain assembles an incredible network of over a billion neurons. Understanding how these connections form during development in order for the brain to function properly is a fundamental question in biology. Much of this wiring takes place during embryonic development. Neurons are generated in the ventricular zone, migrate out, and begin to differentiate. However, neurons are often born in locations some distance from the target cells with which they will ultimately form connections. To form connections, neurons project long axons tipped with a specialized sensing device called a growth cone. The growing axons interact directly with molecules within the environment through which they grow. In order to find their targets, axonal growth cones use guidance molecules that can either attract or repel them. Understanding what these guidance cues are, where they are expressed, and how the growth cone is able to transduce their signal in a directionally specific manner is essential to understanding how the functional brain is constructed. In this chapter, we review what is known about the mechanisms involved in axonal guidance. We discuss how the growth cone is able to sense and respond to its environment and how it is guided by pioneering cells and axons. As examples, we discuss current models for the development of the spinal cord, the cerebral cortex, and the visual and olfactory systems.
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Affiliation(s)
- Céline Plachez
- Department of Anatomy and Neurobiology, University of Maryland, School of Medicine, Baltimore, Maryland 21201, USA
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61
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Mittaz L, Ricardo S, Martinez G, Kola I, Kelly DJ, Little MH, Hertzog PJ, Pritchard MA. Neonatal calyceal dilation and renal fibrosis resulting from loss of Adamts-1 in mouse kidney is due to a developmental dysgenesis. Nephrol Dial Transplant 2004; 20:419-23. [PMID: 15615810 DOI: 10.1093/ndt/gfh603] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND A disintegrin and metalloproteinase with thrombospondin motifs 1, Adamts-1, is important for the development and function of the kidney. Mice lacking this protein present with renal lesions comprising enlarged calyces, and reduced cortex and medulla layers. Our current findings are consistent with the defect occurring due to a developmental dysgenesis. METHODS We generated Adamts-1 null mice, and further investigated their kidney phenotype in a time course study ranging from E18.5 to 12 months of age. Immunohistochemistry was used to assess the localization of type IV collagen, TGF-beta and F4/80-positive macrophages in the kidneys of Adamts-1 null mice compared to wild-type control animals. The expression of Adamts-1 mRNA was determined in metanephric kidney explants by in situ hybridization. RESULTS Adamts-1 null mice have a gross kidney defect. At day 18.5 of gestation, the Adamts-1 null kidney has a normal appearance but at birth when the kidney begins to function, the defect becomes evident. During development of the kidney Adamts-1 expression was specifically detected in the developing loops of Henle, as well as in the proximal and distal convoluted tubules. Expression was not detected in the ureter, ureteric bud or its derivatives as had been previously suggested. At 6 months and 1 year of age, the Adamts-1 null mice displayed interstitial fibrosis in the cortical and medullary regions of the kidney. At 1 year of age, the Adamts-1 null mice displayed mild interstitial matrix expansion associated with increased collagen type IV expression, without apparent tubular dilatation, compared to wild-type animals. Immunohistochemical analysis demonstrated TGF-beta protein localized to infiltrating macrophages and glomeruli of Adamts-1 null mice. CONCLUSIONS Adamts-1 is required for the normal development of the kidney. The defect observed in its absence results from a dysgenic malformation affecting the medulla that becomes apparent at birth, once the kidneys start to function.
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Affiliation(s)
- Laureane Mittaz
- Monash Institute of Reproduction and Development, Monash University, Clayton 3168, Victoria, Australia
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62
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Liu J, Zhang L, Wang D, Shen H, Jiang M, Mei P, Hayden PS, Sedor JR, Hu H. Congenital diaphragmatic hernia, kidney agenesis and cardiac defects associated with Slit3-deficiency in mice. Mech Dev 2004; 120:1059-70. [PMID: 14550534 DOI: 10.1016/s0925-4773(03)00161-8] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Slit3 along with Slit1 and Slit2 comprise the Slit family of proteins. The latter two proteins are known to be involved in axon guidance and cell migration during animal development. However, little is know about the functions of Slit3. We created a Slit3-deficient mouse model from an OmniBank ES cell line with a Slit3 allele trapped by insertional mutagenesis to analyze the in vivo functions of this protein. In this model, congenital diaphragmatic hernia is the most obvious phenotype. Herniation was found to be caused by a defective central tendon (CT) of the diaphragm that remained fused with the liver. Electron microscopic analyses of the defective CT revealed disorganized collagen fibrils that failed to form tight collagen bundles. The hearts of Slit3-deficient mice have an enlarged right ventricle. In addition, 20% of homozygous mice also showed a range of kidney defects that include unilateral or bilateral agenesis of the kidney and ureter, or varying degrees of renal hypoplasia. Thus, we concluded that Slit3 is involved in the development of multiple organ systems that include the diaphragm and the kidney. Slit3-deficient mice represent a genetic animal model for physiological and pathological studies of congenital diaphragmatic hernia.
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Affiliation(s)
- Jianmin Liu
- Rammelkamp Center for Education and Research, MetroHealth Medical Center, Cleveland, OH 44109, USA
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63
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Abstract
Members of the Slit family regulate axon guidance and cell migration. To date, three vertebrate slit1 genes have been identified in mammals and orthologs of two, slit2 and slit3, have been identified in zebrafish. Here, we describe the cloning of full-length cDNAs for two zebrafish slit orthologs, slit1a and slit1b. Both predicted proteins contain the conserved motifs that characterize other vertebrate Slits. slit1a and slit1b are both expressed in the midline, hypochord, telencephalon, and hindbrain. Apart from these shared expression domains, however, their expression patterns largely differ. Whereas slit1a is expressed broadly in the central nervous system (CNS) and in the somites, pectoral fin buds, tail bud, and caudal fin folds, slit1b is expressed in the olfactory system throughout embryonic and larval development, and in the retina during larval stages. Their expression patterns, particularly that of slit1a, suggest that Slit proteins may have roles in tissue morphogenesis in addition to their established roles in axon guidance and cell migration.
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Affiliation(s)
- Lara D Hutson
- Department of Neurobiology and Anatomy, University of Utah Medical Center, Salt Lake City, Utah 84132, USA
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64
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Greenberg JM, Thompson FY, Brooks SK, Shannon JM, Akeson AL. Slit and robo expression in the developing mouse lung. Dev Dyn 2004; 230:350-60. [PMID: 15162513 DOI: 10.1002/dvdy.20045] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Mammalian lung development is mediated through complex interactions between foregut endoderm and surrounding mesenchyme. As airway branching progresses, the mesenchyme undergoes dramatic remodeling and differentiation. Little is understood about the mechanisms that direct mesenchymal organization during lung development. A screen for candidate genes mediating this process identified Slit, a ligand for the Roundabout (Robo) receptor previously associated with guidance of axonal projections during central nervous system development. Here, we demonstrate by in situ hybridization that two Slit genes (Slit-2 and Slit-3) and two Robo genes (Robo-1 and Robo-2) are expressed in fetal lung mesenchyme. Slit-2 and Robo-1 expression is present throughout mesenchyme at midgestation and is not detectable by newborn day 1. Slit-3 and Robo-2 expression is restricted to specific, complementary subsets of mesenchyme. Robo-2 is expressed in mesenchymal cells immediately adjacent to large airways, whereas Slit-3 expression predominates in mesenchyme remote from airway epithelium. The temporal and spatial distribution of Slit and Robo mRNAs indicate that these genes may direct the functional organization and differentiation of fetal lung mesenchyme.
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Affiliation(s)
- James M Greenberg
- Divisions of Pulmonary Biology and Neonatology, Cincinnati Children's Hospital Research Foundation, Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio 45229, USA.
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65
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Shah MM, Sampogna RV, Sakurai H, Bush KT, Nigam SK. Branching morphogenesis and kidney disease. Development 2004; 131:1449-62. [PMID: 15023929 DOI: 10.1242/dev.01089] [Citation(s) in RCA: 129] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Branching morphogenesis in the kidney is a tightly regulated, complex process and its disruption potentially can lead to a broad spectrum of diseases, ranging from rare hereditary syndromes to common conditions such as hypertension and chronic kidney failure. This review synthesizes data on branching during kidney development derived from in vitro and in vivo rodent studies and to apply them to human diseases. It discusses how the broad organization of molecular interactions during kidney development might provide a mechanistic framework for understanding disorders related to aberrant branching.
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Affiliation(s)
- Mita M Shah
- Department of Pediatrics, University of California, San Diego, CA 92093-0693, USA
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66
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Stuart RO, Bush KT, Nigam SK. Changes in gene expression patterns in the ureteric bud and metanephric mesenchyme in models of kidney development. Kidney Int 2003; 64:1997-2008. [PMID: 14633122 DOI: 10.1046/j.1523-1755.2003.00383.x] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND In a recent study, the pattern of gene expression during development of the rat kidney was analyzed using high-density DNA array technology (Stuart RO, Bush KT, Nigam SK, Proc Natl Acad Sci USA 98:5649-5654, 2001). This approach, while shedding light on global patterns of gene expression in the developing kidney, does not provide insight into the contributions of genes that might be part of the morphogenetic program of the ureteric bud (UB) and metanephric mesenchyme (MM), the two tissues that interact closely during nephron formation. METHODS We have now used high-density DNA arrays together with a double in vitro transcription (dIVT) approach to examine gene expression patterns in in vitro models for morphogenesis of the rat UB (isolated UB culture) and MM (coculture with embryonic spinal cord) and compared this data with patterns of gene expression in the whole embryonic kidney at different stages of development. RESULTS The results indicate that different sets of genes are expressed in the UB and MM as morphogenesis occurs. The dIVT data from the in vitro UB and MM culture models was clustered hierarchically with single IVT data from the whole embryonic kidney obtained at different stages of development, and the global patterns of gene expression were remarkably compatible, supporting the validity of the approach. The potential roles of genes whose expression was associated with the individual tissues were examined, and several pathways were identified that could have roles in kidney development. For example, hepatocyte nuclear factor-6 (HNF-6), a transcription factor potentially upstream in a pathway leading to the expression of KSP-cadherin was highly expressed in the UB. Embigin, a cell adhesion molecule important in cell/extracellular matrix (ECM) interactions, was also found in the UB and may serve as a Dolichos biflorus binding protein in the kidney. ADAM10, a disintegrin-metalloprotease involved in Delta-Notch signaling and perhaps Slit-Robo signaling, was also highly expressed in late UB. Celsr-3, a protein, which along with members of the Wnt-frizzled transduction cascade, might be involved in the polarization of the forming nephron, was found to be highly expressed in differentiating MM. DDR2, a member of the discoidin domain receptor family, which is thought to function in the activation of matrix metalloproteinase-2 (MMP-2), was also found to be highly expressed in differentiating MM. It is also interesting to note that almost 10% of the highly expressed genes in both tissues were associated with neuronal growth and/or differentiation. CONCLUSION The data presented in this study point to the power of combining in vitro models of kidney development with high-density DNA arrays to identify the genes involved in the morphogenetic process. Clear differences were found between patterns of genes expressed by the UB and MM at different stages of morphogenesis, and many of these were associated with neuronal growth and/or differentiation. Together, the high-density microarray data not only begin to suggest how separate genetic programs in the UB and MM orchestrate the formation of the whole kidney, but also suggest the involvement of heretofore largely unexplored developmental pathways (involving HNF-6, ADAM-10, Celsr-3, DDR2, and other genes) in nephrogenesis.
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Affiliation(s)
- Robert O Stuart
- Department of Medicine, University of California, San Diego, California, USA.
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Huber AB, Kolodkin AL, Ginty DD, Cloutier JF. Signaling at the growth cone: ligand-receptor complexes and the control of axon growth and guidance. Annu Rev Neurosci 2003; 26:509-63. [PMID: 12677003 DOI: 10.1146/annurev.neuro.26.010302.081139] [Citation(s) in RCA: 562] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The guidance of axons during the establishment of the nervous system is mediated by a variety of extracellular cues that govern cytoskeletal dynamics in axonal growth cones. A large number of these guidance cues and their cell-surface receptors have now been identified, and the intracellular signaling pathways by which these cues induce cytoskeletal rearrangements are becoming defined. This review summarizes our current understanding of the major families of axon guidance cues and their receptors, with a particular emphasis on receptor signaling mechanisms. We also discuss recent advances in understanding receptor cross talk and how the activities of guidance cues and their receptors are modulated during neural development.
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Affiliation(s)
- Andrea B Huber
- Department of Neuroscience, Howard Hughes Medical Institute, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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68
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Wilkinson L, Kolle G, Wen D, Piper M, Scott J, Little M. CRIM1 regulates the rate of processing and delivery of bone morphogenetic proteins to the cell surface. J Biol Chem 2003; 278:34181-8. [PMID: 12805376 DOI: 10.1074/jbc.m301247200] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The Crim1 gene is predicted to encode a transmembrane protein containing six von Willebrand-like cysteine-rich repeats (CRRs) similar to those in the BMP-binding antagonist Chordin (Chrd). In this study, we verify that CRIM1 is a glycosylated, Type I transmembrane protein and demonstrate that the extracellular CRR-containing domain can also be secreted, presumably via processing at the membrane. We have previously demonstrated Crim1 expression at sites consistent with an interaction with bone morphogenetic proteins (BMPs). Here we show that CRIM1 can interact with both BMP4 and BMP7 via the CRR-containing portion of the protein and in so doing acts as an antagonist in three ways. CRIM1 binding of BMP4 and -7 occurs when these proteins are co-expressed within the Golgi compartment of the cell and leads to (i) a reduction in the production and processing of preprotein to mature BMP, (ii) tethering of pre-BMP to the cell surface, and (iii) an effective reduction in the secretion of mature BMP. Functional antagonism was verified by examining the effect of co-expression of CRIM1 and BMP4 on metanephric explant culture. The presence of CRIM1 reduced the effective BMP4 concentration of the media, thereby acting as a BMP4 antagonist. Hence, CRIM1 modulates BMP activity by affecting its processing and delivery to the cell surface.
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Affiliation(s)
- Lorine Wilkinson
- Institute for Molecular Bioscience, The University of Queensland, Brisbane, Queensland 4072, Australia
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69
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Anselmo MA, Dalvin S, Prodhan P, Komatsuzaki K, Aidlen JT, Schnitzer JJ, Wu JY, Kinane TB. Slit and robo: expression patterns in lung development. Gene Expr Patterns 2003; 3:13-9. [PMID: 12609596 DOI: 10.1016/s1567-133x(02)00095-9] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
First described as an axonal guidance cue through its repulsive effect on neurons expressing its receptor Roundabout (Robo), the Slit ligand has effects on cell migration, axon branching and elongation. Indirect evidence implicates Slit and Robo in lung development. We now demonstrate that Slit-2 and Slit-3 are developmentally regulated in embryonic murine lung. Immunohistochemistry demonstrates Slit-2 and Slit-3 expression by the pulmonary mesenchyme and airway epithelium. Robo-1 and Robo-2 are also expressed by the developing mesenchyme and airway epithelium. As lung development progresses, Robo-1 and Robo-2 expression localizes to only the airway epithelium. We conclude Slit/Robo are expressed in temporo-spatially adjacent domains suggesting interactive roles in pulmonary bronchiolar development.
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Affiliation(s)
- Mark A Anselmo
- Pediatric Pulmonary Unit, Massachusetts General Hospital for Children, Harvard Medical School, Jackson 14, GRJ 1416, 55 Fruit St, Boston, MA 02114, USA
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70
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Abstract
First isolated in the fly and now characterised in vertebrates, the Slit proteins have emerged as pivotal components controlling the guidance of axonal growth cones and the directional migration of neuronal precursors. As well as extensive expression during development of the central nervous system (CNS), the Slit proteins exhibit a striking array of expression sites in non-neuronal tissues, including the urogenital system, limb primordia and developing eye. Zebrafish Slit has been shown to mediate mesodermal migration during gastrulation, while Drosophila slit guides the migration of mesodermal cells during myogenesis. This suggests that the actions of these secreted molecules are not simply confined to the sphere of CNS development, but rather act in a more general fashion during development and throughout the lifetime of an organism. This review focuses on the non-neuronal activities of Slit proteins, highlighting a common role for the Slit family in cellular migration.
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Affiliation(s)
- Michael Piper
- Institute for Molecular Bioscience, University of Queensland, Brisbane, Australia
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71
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Abstract
The receptor Roundabout-1 (Robo1) and its ligand Slit are known to influence axon guidance and central nervous system (CNS) patterning in both vertebrate and nonvertebrate systems. Although Robo-Slit interactions mediate axon guidance in the Drosophila CNS, their role in establishing the early axon scaffold in the embryonic vertebrate brain remains unclear. We report here the identification and expression of a Xenopus Robo1 orthologue that is highly homologous to mammalian Robo1. By using overexpression studies and immunohistochemical and in situ hybridization techniques, we have investigated the role of Robo1 in the development of a subset of neurons and axon tracts in the Xenopus forebrain. Robo1 is expressed in forebrain nuclei and in neuroepithelial cells underlying the main axon tracts. Misexpression of Robo1 led to aberrant development of axon tracts as well as the ectopic differentiation of forebrain neurons. These results implicate Robo1 in both neuronal differentiation and axon guidance in embryonic vertebrate forebrain.
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Affiliation(s)
- R M Connor
- Department of Anatomy and Developmental Biology, School of Biomedical Sciences, University of Queensland, Brisbane 4072, Australia
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72
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Piscione TD, Rosenblum ND. The molecular control of renal branching morphogenesis: current knowledge and emerging insights. Differentiation 2002; 70:227-46. [PMID: 12190985 DOI: 10.1046/j.1432-0436.2002.700602.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Mammalian kidney development requires the formation of a patterned, branched network of collecting ducts, a process termed renal branching morphogenesis. Disruption of renal branching morphogenesis during human kidney development results in renal dysplasia, the major cause of renal failure in young children. Genetic evidence, combined with in vitro data, have implicated transcription factors, secreted growth factors, and cell surface signaling peptides as critical regulators of renal branching morphogenesis. This review discusses the current knowledge regarding the regulation of renal branching morphogenesis in vivo provided by the analysis of genetic mutations in mice and humans which disrupt collecting duct system development. In addition, in vivo and in vitro evidence regarding the functions of several other gene families are considered, rendering new insight into emerging regulatory roles for these molecules in renal branching morphogenesis.
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Affiliation(s)
- Tino D Piscione
- Program in Development Biology, Division of Nephrology, The Hospital for Sick Children, University of Toronto, 555 University Ave., Ontario, M5G1X8, Canada
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73
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Xian J, Clark KJ, Fordham R, Pannell R, Rabbitts TH, Rabbitts PH. Inadequate lung development and bronchial hyperplasia in mice with a targeted deletion in the Dutt1/Robo1 gene. Proc Natl Acad Sci U S A 2001; 98:15062-6. [PMID: 11734623 PMCID: PMC64983 DOI: 10.1073/pnas.251407098] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2001] [Indexed: 11/18/2022] Open
Abstract
Chromosome 3 allele loss in preinvasive bronchial abnormalities and carcinogen-exposed, histologically normal bronchial epithelium indicates that it is an early, possibly the first, somatic genetic change in lung tumor development. Candidate tumor suppressor genes have been isolated from within distinct 3p regions implicated by heterozygous and homozygous allele loss. We have proposed that DUTT1, nested within homozygously deleted regions at 3p12-13, is the tumor suppressor gene that deletion-mapping and tumor suppression assays indicate is located in proximal 3p. The same gene, ROBO1 (accession number ), was independently isolated as the human homologue of the Drosophila gene, Roundabout. The gene, coding for a receptor with a domain structure of the neural-cell adhesion molecule family, is widely expressed and has been implicated in the guidance and migration of axons, myoblasts, and leukocytes in vertebrates. A deleted form of the gene, which mimics a naturally occurring, tumor-associated human homozygous deletion of exon 2 of DUTT1/ROBO1, was introduced into the mouse germ line. Mice homozygous for this targeted mutation, which eliminates the first Ig domain of Dutt1/Robo1, frequently die at birth of respiratory failure because of delayed lung maturation. Lungs from these mice have reduced air spaces and increased mesenchyme, features that are present some days before birth. Survivors acquire extensive bronchial epithelial abnormalities including hyperplasia, providing evidence of a functional relationship between a 3p gene and the development of bronchial abnormalities associated with early lung cancer.
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Affiliation(s)
- J Xian
- Medical Research Council (MRC) Molecular Oncology Group, Department of Oncology, University of Cambridge, MRC Centre, United Kingdom
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74
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Hao JC, Yu TW, Fujisawa K, Culotti JG, Gengyo-Ando K, Mitani S, Moulder G, Barstead R, Tessier-Lavigne M, Bargmann CI. C. elegans slit acts in midline, dorsal-ventral, and anterior-posterior guidance via the SAX-3/Robo receptor. Neuron 2001; 32:25-38. [PMID: 11604136 DOI: 10.1016/s0896-6273(01)00448-2] [Citation(s) in RCA: 175] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Robo receptors interact with ligands of the Slit family. The nematode C. elegans has one Robo receptor (SAX-3) and one Slit protein (SLT-1), which direct ventral axon guidance and guidance at the midline. In larvae, slt-1 expression in dorsal muscles repels axons to promote ventral guidance. SLT-1 acts through the SAX-3 receptor, in parallel with the ventral attractant UNC-6 (Netrin). Removing both UNC-6 and SLT-1 eliminates all ventral guidance information for some axons, revealing an underlying longitudinal guidance pathway. In the embryo, slt-1 is expressed at high levels in anterior epidermis. Embryonic expression of SLT-1 provides anterior-posterior guidance information to migrating CAN neurons. Surprisingly, slt-1 mutants do not exhibit the nerve ring and epithelial defects of sax-3 mutants, suggesting that SAX-3 has both Slit-dependent and Slit-independent functions in development.
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Affiliation(s)
- J C Hao
- Howard Hughes Medical Institute, Department of Anatomy, The University of California, San Francisco, CA 94143, USA
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75
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Little MH, Wilkinson L, Brown DL, Piper M, Yamada T, Stow JL. Dual trafficking of Slit3 to mitochondria and cell surface demonstrates novel localization for Slit protein. Am J Physiol Cell Physiol 2001; 281:C486-95. [PMID: 11443047 DOI: 10.1152/ajpcell.2001.281.2.c486] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Drosophila slit is a secreted protein involved in midline patterning. Three vertebrate orthologs of the fly slit gene, Slit1, 2, and 3, have been isolated. Each displays overlapping, but distinct, patterns of expression in the developing vertebrate central nervous system, implying conservation of function. However, vertebrate Slit genes are also expressed in nonneuronal tissues where their cellular locations and functions are unknown. In this study, we characterized the cellular distribution and processing of mammalian Slit3 gene product, the least evolutionarily conserved of the vertebrate Slit genes, in kidney epithelial cells, using both cellular fractionation and immunolabeling. Slit3, but not Slit2, was predominantly localized within the mitochondria. This localization was confirmed using immunoelectron microscopy in cell lines and in mouse kidney proximal tubule cells. In confluent epithelial monolayers, Slit3 was also transported to the cell surface. However, we found no evidence of Slit3 proteolytic processing similar to that seen for Slit2. We demonstrated that Slit3 contains an NH(2)-terminal mitochondrial localization signal that can direct a reporter green fluorescent protein to the mitochondria. The equivalent region from Slit1 cannot elicit mitochondrial targeting. We conclude that Slit3 protein is targeted to and localized at two distinct sites within epithelial cells: the mitochondria, and then, in more confluent cells, the cell surface. Targeting to both locations is driven by specific NH(2)-terminal sequences. This is the first examination of Slit protein localization in nonneuronal cells, and this study implies that Slit3 has potentially unique functions not shared by other Slit proteins.
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Affiliation(s)
- M H Little
- Institute for Molecular Bioscience and Center for Functional and Applied Genomics, University of Queensland, St. Lucia, 4072, Brisbane, Queensland, Australia.
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76
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Lee JS, Ray R, Chien CB. Cloning and expression of three zebrafish roundabout homologs suggest roles in axon guidance and cell migration. Dev Dyn 2001; 221:216-30. [PMID: 11376489 DOI: 10.1002/dvdy.1136] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
We report the cloning and expression patterns of three novel zebrafish Roundabout homologs. The Roundabout (robo) gene encodes a transmembrane receptor that is essential for axon guidance in Drosophila and Robo family members have been implicated in cell migration. Analysis of extracellular domains and conserved cytoplasmic motifs shows that zebrafish Robo1 and Robo2 are orthologs of mammalian Robo1 and Robo2, respectively, while zebrafish Robo3 is likely to be an ortholog of mouse Rig-1. The three zebrafish robos are expressed in distinct but overlapping patterns during embryogenesis. They are highly expressed in the developing nervous system, including the olfactory system, visual system, hindbrain, cranial ganglia, spinal cord, and posterior lateral line primordium. They are also expressed in several nonneuronal tissues, including somites and fin buds. The timing and patterns of expression suggest roles for zebrafish robos in axon guidance and cell migration. Wiley-Liss, Inc.
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Affiliation(s)
- J S Lee
- Department of Neurobiology and Anatomy, University of Utah, 50 North Medical Drive, Salt Lake City, UT 84132, USA
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77
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Kullander K, Croll SD, Zimmer M, Pan L, McClain J, Hughes V, Zabski S, DeChiara TM, Klein R, Yancopoulos GD, Gale NW. Ephrin-B3 is the midline barrier that prevents corticospinal tract axons from recrossing, allowing for unilateral motor control. Genes Dev 2001; 15:877-88. [PMID: 11297511 PMCID: PMC312668 DOI: 10.1101/gad.868901] [Citation(s) in RCA: 204] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Growing axons follow highly stereotypical pathways, guided by a variety of attractive and repulsive cues, before establishing specific connections with distant targets. A particularly well-known example that illustrates the complexity of axonal migration pathways involves the axonal projections of motor neurons located in the motor cortex. These projections take a complex route during which they first cross the midline, then form the corticospinal tract, and ultimately connect with motor neurons in the contralateral side of the spinal cord. These obligatory contralateral connections account for why one side of the brain controls movement on the opposing side of the body. The netrins and slits provide well-known midline signals that regulate axonal crossings at the midline. Herein we report that a member of the ephrin family, ephrin-B3, also plays a key role at the midline to regulate axonal crossing. In particular, we show that ephrin-B3 acts as the midline barrier that prevents corticospinal tract projections from recrossing when they enter the spinal gray matter. We report that in ephrin-B3(-/-) mice, corticospinal tract projections freely recross in the spinal gray matter, such that the motor cortex on one side of the brain now provides bilateral input to the spinal cord. This neuroanatomical abnormality in ephrin-B3(-/-) mice correlates with loss of unilateral motor control, yielding mice that simultaneously move their right and left limbs and thus have a peculiar hopping gait quite unlike the alternate step gait displayed by normal mice. The corticospinal and walking defects in ephrin-B3(-/-) mice resemble those recently reported for mice lacking the EphA4 receptor, which binds ephrin-B3 as well as other ephrins, suggesting that the binding of EphA4-bearing axonal processes to ephrin-B3 at the midline provides the repulsive signal that prevents corticospinal tract projections from recrossing the midline in the developing spinal cord.
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Affiliation(s)
- K Kullander
- European Molecular Biology Laboratory, D-69117 Heidelberg, Germany
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