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de Castro F. Wiring Olfaction: The Cellular and Molecular Mechanisms that Guide the Development of Synaptic Connections from the Nose to the Cortex. Front Neurosci 2009; 3:52. [PMID: 20582279 PMCID: PMC2858608 DOI: 10.3389/neuro.22.004.2009] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2009] [Accepted: 11/04/2009] [Indexed: 12/27/2022] Open
Abstract
Within the central nervous system, the olfactory system fascinates by its developmental and physiological particularities, and is one of the most studied models to understand the mechanisms underlying the guidance of growing axons to their appropriate targets. A constellation of contact-mediated (laminins, CAMs, ephrins, etc.) and secreted mechanisms (semaphorins, slits, growth factors, etc.) are known to play different roles in the establishment of synaptic interactions between the olfactory epithelium, olfactory bulb (OB) and olfactory cortex. Specific mechanisms of this system (including the amazing family of about 1000 different olfactory receptors) have been also proposed. In the last years, different reviews have focused in partial sights, specially in the mechanisms involved in the formation of the olfactory nerve, but a detailed review of the mechanisms implicated in the development of the connections among the different olfactory structures (olfactory epithelium, OB, olfactory cortex) remains to be written. In the present work, we afford this systematic review: the different cellular and molecular mechanisms which rule the formation of the olfactory nerve, the lateral olfactory tract and the intracortical connections, as well as the few data available regarding the accessory olfactory system. These mechanisms are compared, and the implications of the differences and similarities discussed in this fundamental scenario of ontogeny.
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Affiliation(s)
- Fernando de Castro
- Grupo de Neurobiología del Desarrollo-GNDe, Hospital Nacional de Parapléjicos Toledo, Spain
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Understanding the mechanisms of callosal development through the use of transgenic mouse models. Semin Pediatr Neurol 2009; 16:127-42. [PMID: 19778710 DOI: 10.1016/j.spen.2009.07.003] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The cerebral cortex is the area of the brain where higher-order cognitive processing occurs. The 2 hemispheres of the cerebral cortex communicate through one of the largest fiber tracts in the brain, the corpus callosum. Malformation of the corpus callosum in human beings occurs in 1 in 4000 live births, and those afflicted experience an extensive range of neurologic disorders, from relatively mild to severe cognitive deficits. Understanding the molecular and cellular processes involved in these disorders would therefore assist in the development of prognostic tools and therapies. During the past 3 decades, mouse models have been used extensively to determine which molecules play a role in the complex regulation of corpus callosum development. This review provides an update on these studies, as well as highlights the value of using mouse models with the goal of developing therapies for human acallosal syndromes.
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Le A, Zielinski R, He C, Crow MT, Biswal S, Tuder RM, Becker PM. Pulmonary epithelial neuropilin-1 deletion enhances development of cigarette smoke-induced emphysema. Am J Respir Crit Care Med 2009; 180:396-406. [PMID: 19520907 PMCID: PMC2742758 DOI: 10.1164/rccm.200809-1483oc] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2008] [Accepted: 06/09/2009] [Indexed: 01/03/2023] Open
Abstract
RATIONALE Cigarette smoke (CS) exposure is an important risk factor for chronic obstructive pulmonary disease; however, not all smokers develop disease, suggesting that other factors influence disease development. OBJECTIVES We sought to determine whether neuropilin-1 (Nrp1), an integral component of receptor complexes mediating alveolar septation and vascular development, was involved in maintenance of normal alveolar structure, and/or altered susceptibility to the effects of CS. METHODS Transgenic mice were generated to achieve inducible lung-specific deletion of epithelial Nrp1. We determined whether conditional Nrp1 deletion altered airspace size, then compared the effects of chronic CS or filtered air exposure on airspace size, inflammation, and the balance between cell death and proliferation in conditionally Nrp1-deficient adult mice and littermate controls. Finally, we evaluated the effects of Nrp1 silencing on cell death after acute exposure of A549 cells to cigarette smoke extract or short chain ceramides. MEASUREMENTS AND MAIN RESULTS Genetic deletion of epithelial Nrp1 in either postnatal or adult lungs resulted in a small increase in airspace size. More notably, both airspace enlargement and apoptosis of type I and type II alveolar epithelial cells were significantly enhanced following chronic CS exposure in conditionally Nrp1-deficient adult mice. Silencing of Nrp1 in A549 cells did not alter cell survival after vehicle treatment but significantly augmented apoptosis after exposure to cigarette smoke extract or ceramide. CONCLUSIONS These data support a role for epithelial Nrp1 in the maintenance of normal alveolar structure and suggest that dysregulation of Nrp1 expression may promote epithelial cell death in response to CS exposure, thereby enhancing emphysema development.
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Affiliation(s)
- Anne Le
- Division of Pulmonary and Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21224, USA
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Enhancement of vascular progenitor potential by protein kinase A through dual induction of Flk-1 and Neuropilin-1. Blood 2009; 114:3707-16. [PMID: 19706882 DOI: 10.1182/blood-2008-12-195750] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Fine tuning of vascular endothelial growth factor (VEGF) signaling is critical in endothelial cell (EC) differentiation and vascular development. Nevertheless, the system for regulating the sensitivity of VEGF signaling has remained unclear. Previously, we established an embryonic stem cell culture reproducing early vascular development using Flk1 (VEGF receptor-2)+ cells as common progenitors, and demonstrated that cyclic adenosine monophosphate (cAMP) enhanced VEGF-induced EC differentiation. Here we show that protein kinase A (PKA) regulates sensitivity of Flk1+ vascular progenitors to VEGF signaling for efficient EC differentiation. Blockade of PKA perturbed EC differentiation and vascular formation in vitro and ex vivo. Overexpression of constitutive active form of PKA (CA-PKA) potently induced EC differentiation and vascular formation. Expression of Flk1 and Neuropilin-1 (NRP1), which form a selective and sensitive receptor for VEGF(165), was increased only in CA-PKA-expressing progenitors, enhancing the sensitivity of the progenitors to VEGF(165) by more than 10 times. PKA activation induced the formation of a VEGF(165), Flk1, and NRP1 protein complex in vascular progenitors. These data indicate that PKA regulates differentiation potential of vascular progenitors to be endothelial competent via the dual induction of Flk1 and NRP1. This new-mode mechanism regulating "progenitor sensitivity" would provide a novel understanding in vascular development and regeneration.
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Lu Y, Xiang H, Liu P, Tong RR, Watts RJ, Koch AW, Sandoval WN, Damico LA, Wong WL, Meng YG. Identification of circulating neuropilin-1 and dose-dependent elevation following anti-neuropilin-1 antibody administration. MAbs 2009; 1:364-9. [PMID: 20068394 DOI: 10.4161/mabs.1.4.8885] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Neuropilin-1 (NRP1) acts as a co-receptor for class 3 semaphorins and vascular endothelial growth factor and is an attractive angiogenesis target for cancer therapy. In addition to the transmembrane form, naturally occurring soluble NRP1 proteins containing part of the extracellular domain have been identified in tissues and a cell line. We developed ELISAs to study the existence of circulating NRP1 and to quantify it in serum. As measured by ELISAs, circulating NRP1 levels in mice, rats, monkeys and humans were 427 +/- 77, 20 +/- 3, 288 +/- 86 and 322 +/- 82 ng/ml (mean +/- standard deviation; n > or = 10), respectively. Anti-NRP1(B), a human monoclonal antibody, has been selected from a synthetic phage library. A 4-fold increase in circulating NRP1 was observed in mice receiving a single dose of 10 mg/kg anti-NRP1(B) antibody. In rats and monkeys receiving single injections of anti-NRP1(B) at different dose levels, higher doses of antibody resulted in greater and more prolonged increases in circulating NRP1. Maximum increases were 56- and 7-fold for rats and monkeys receiving 50 mg/kg anti-NRP1(B), respectively. In addition to the soluble NRP1 isoforms, for the first time, a approximately 120 kDa circulating NRP1 protein containing the complete extracellular domain was detected in serum by western blot and mass spectrometry analysis. This protein increased more than the putative soluble NRP1 bands in anti-NRP1(B) treated mouse, rat and monkey sera compared with untreated controls, suggesting that anti-NRP1(B) induced membrane NRP1 shedding.
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Affiliation(s)
- Yanmei Lu
- Department of Assay and Automation Technology, Genentech Inc., South San Francisco, CA 94080, USA.
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Gong Q, Chen H, Farbman AI. Olfactory sensory axon growth and branching is influenced by sonic hedgehog. Dev Dyn 2009; 238:1768-76. [PMID: 19517566 PMCID: PMC2776656 DOI: 10.1002/dvdy.22005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Olfactory sensory neuron (OSN) axons extend from the olfactory epithelium to the olfactory bulb without branching until they reach their target region, the glomerulus. In this report, we present evidence to support the involvement of sonic hedgehog in promoting rat olfactory sensory axons to branch and to enter into the glomerulus. Sonic hedgehog (Shh) protein is detected in the glomeruli of the olfactory bulb, whereas its transcript is expressed in the mitral and tufted cells, suggesting that Shh in the glomeruli is produced by mitral and tufted cells. In primary OSN cultures, Shh-N peptide promotes olfactory axon branching. When Shh function is neutralized in vivo by its antibody, growth of newly generated OSN axons into the glomeruli is vastly reduced.
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Affiliation(s)
- Qizhi Gong
- Department of Cell Biology and Human Anatomy, School of Medicine, University of California, Davis, California 95616, USA.
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Expression of Sema3D in subsets of neurons in the developing dorsal root ganglia of the rat. Neurosci Lett 2009; 455:17-21. [DOI: 10.1016/j.neulet.2009.03.050] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2008] [Revised: 03/04/2009] [Accepted: 03/12/2009] [Indexed: 11/19/2022]
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Hatanaka Y, Matsumoto T, Yanagawa Y, Fujisawa H, Murakami F, Masu M. Distinct roles of neuropilin 1 signaling for radial and tangential extension of callosal axons. J Comp Neurol 2009; 514:215-25. [PMID: 19296474 DOI: 10.1002/cne.22021] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Cortical excitatory neurons migrate from their origin in the ventricular zone (VZ) toward the pial surface. During migration, these neurons exhibit a stellate shape in the intermediate zone (IZ), transform into bipolar cells, and then initiate radial migration, extending a trailing process, which may lead to an axon. Here we examined the role of neuropilin 1 (NRP1) in these developmental events. Both NRP1 mRNA and protein were highly expressed in the IZ, where stellate-shaped cells were located. DiI labeling experiments showed that neuronal migration occurred normally in Nrp1 mutant mice up to embryonic day (E) 14.5, the latest day to which the mutant survives, with only subtle axonal defasciculation. However, interference with Nrp1 signaling at a later stage caused pathfinding errors: when a dominant negative form of Nrp1 was electroporated into the cortical VZ cells at E12.5 or E15.5 and examined perinatally, guidance errors were found in tangential axonal extension toward the midline. In contrast, no significant effect was noted on the migration of cortical excitatory neurons. These findings indicate that NRP1 plays an important role in the guidance of callosal axons originating from cortical excitatory neurons but does not support a role in their migration. Moreover, insofar as radial axonal extension within the cortical plate was unaffected, the present findings imply that molecular mechanisms for the axonal extension of excitatory neurons within the cortical plate are distinct from those in the white matter.
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Affiliation(s)
- Yumiko Hatanaka
- Department of Molecular Neurobiology, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan.
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Dallas NA, Gray MJ, Xia L, Fan F, van Buren G, Gaur P, Samuel S, Lim SJ, Arumugam T, Ramachandran V, Wang H, Ellis LM. Neuropilin-2-mediated tumor growth and angiogenesis in pancreatic adenocarcinoma. Clin Cancer Res 2009; 14:8052-60. [PMID: 19088020 DOI: 10.1158/1078-0432.ccr-08-1520] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Neuropilin-2 (NRP-2) is a coreceptor for vascular endothelial growth factor (VEGF) on endothelial cells. NRP-2 is overexpressed in pancreatic ductal adenocarcinoma (PDAC) cells relative to nonmalignant ductal epithelium. This study determined the role of NRP-2 in PDAC cells. EXPERIMENTAL DESIGN NRP-2 expression was reduced in PDAC cells with stable short-hairpin RNA (shRNA) transfection. Western blotting was done to evaluate signaling intermediates. Migration and invasion studies were carried out in Boyden chambers. Anchorage-independent growth was assessed by soft-agar colony formation. In vivo growth was evaluated using murine subcutaneous and orthotopic xenograft models. Immunohistochemical analysis evaluated in vivo proliferation and angiogenesis. RESULTS shRNA-NRP-2 decreased NRP-2 levels without affecting neuropilin-1 levels. Akt activation was decreased in clones with reduced NRP-2 (shRNA-NRP-2). shRNA-NRP-2 cells showed decreased migration, invasion, and anchorage-independent growth compared with control cells. In vitro proliferation rates were similar in control- and shRNA-transfected cells. Subcutaneous and orthotopic xenografts from shRNA-transfected cells were significantly smaller than those resulting from control-transfected cells (P < 0.05). Furthermore, shRNA-NRP-2 tumors exhibited less cellular proliferation and decreased microvascular area relative to control tumors (P < 0.05). Constitutive expression of the angiogenic mediator Jagged-1 was reduced in shRNA-NRP-2 cells, whereas vascular endothelial growth factor levels were unchanged. CONCLUSION Reduction of NRP-2 expression in PDAC cells decreased survival signaling, migration, invasion, and ability to grow under anchorage-independent conditions. In vivo, reduction of NRP-2 led to decreased growth of xenograft tumors and decreased vascular area, which was associated with decreased Jagged-1 levels. NRP-2 is a potential therapeutic target on PDAC cells.
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Affiliation(s)
- Nikolaos A Dallas
- Department of Surgical Oncology, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77230-1402, USA
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Vasudevan A, Bhide PG. Angiogenesis in the embryonic CNS: a new twist on an old tale. Cell Adh Migr 2008; 2:167-9. [PMID: 19262109 DOI: 10.4161/cam.2.3.6485] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
The central nervous system (CNS) acquires its vasculature by angiogenesis, a process consisting of proliferation of endothelial cells in existing blood vessels or vascular plexuses and leading to formation of new blood vessels. Angiogenesis begins early in CNS development and continues throughout life. Prevailing notions depict CNS angiogenesis as a passive process driven primarily by demands for oxygen and other nutrients by the growing neuronal populations. Thus, although the CNS vasculature develops concomitant with neuronal identities, which emerge under the influence of compartment-specific cell autonomous factors, cell autonomous patterning signals are not considered to instruct vascular development. We have challenged this prevailing notion by showing that angiogenesis in the mouse telencephalon progresses in an orderly, ventral-to-dorsal gradient regulated in a cell-autonomous manner by compartment-specific homeobox transcription factors. These are the same transcription factors that confer compartmental identities on telencephalic neurons and progenitor populations. Thus, the same cell-autonomous, regional patterning signals that regulate development of telencephalic neuronal networks also regulate development of telencephalic vascular networks, underscoring shared mechanisms in CNS vascular and neuronal development. These novel concepts represent a new twist in the intriguing tale of CNS angiogenesis and offer new perspectives on telencephalic regionalization and histogenesis principles.
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Affiliation(s)
- Anju Vasudevan
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, Massachusetts 02129, USA.
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61
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Prahst C, Héroult M, Lanahan AA, Uziel N, Kessler O, Shraga-Heled N, Simons M, Neufeld G, Augustin HG. Neuropilin-1-VEGFR-2 complexing requires the PDZ-binding domain of neuropilin-1. J Biol Chem 2008; 283:25110-25114. [PMID: 18628209 DOI: 10.1074/jbc.c800137200] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Vascular endothelial growth factor (VEGF) acts as a hierarchically high switch of the angiogenic cascade by interacting with its high affinity VEGF receptors and with neuropilin co-receptors. VEGF(165) binds to both Neuropilin-1 (NP-1) and VEGFR-2, and it is believed that ligand binding forms an extracellular bridge between both molecules. This leads to complex formation, thereby enhancing VEGFR-2 phosphorylation and subsequent signaling. We found that inhibition of VEGF receptor (VEGFR) phosphorylation reduced complex formation between NP-1 and VEGFR-2, suggesting a functional role of the cytoplasmic domain of VEGFR-2 for complex formation. Correspondingly, deleting the PDZ-binding domain of NP-1 decreased complex formation, indicating that extracellular VEGF(165) binding is not sufficient for VEGFR-2-NP-1 interaction. Synectin is an NP-1 PDZ-binding domain-interacting molecule. Experiments in Synectin-deficient endothelial cells revealed reduced VEGFR-2-NP-1 complex formation, suggesting a role for Synectin in VEGFR-2-NP-1 signaling. Taken together, the experiments have identified a novel mechanism of NP-1 interaction with VEGFR-2, which involves the cytoplasmic domain of NP-1.
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Affiliation(s)
- Claudia Prahst
- Joint Research Division Vascular Biology of the Medical Faculty Mannheim (CBTM), University of Heidelberg, and the German Cancer Research Center (DKFZ), D-69120 Heidelberg, Germany
| | - Mélanie Héroult
- Joint Research Division Vascular Biology of the Medical Faculty Mannheim (CBTM), University of Heidelberg, and the German Cancer Research Center (DKFZ), D-69120 Heidelberg, Germany
| | - Anthony A Lanahan
- Angiogenesis Research Center and Section of Cardiology, Department of Medicine, Dartmouth Medical School, Lebanon, New Hampshire 03756
| | - Noa Uziel
- Cancer and Vascular Biology Research Center, Rappaport Research Institute in the Medical Sciences, The Bruce Rappaport Faculty of Medicine, Technion, Israel Institute of Technology, Haifa 31096, Israel
| | - Ofra Kessler
- Cancer and Vascular Biology Research Center, Rappaport Research Institute in the Medical Sciences, The Bruce Rappaport Faculty of Medicine, Technion, Israel Institute of Technology, Haifa 31096, Israel
| | - Niva Shraga-Heled
- Cancer and Vascular Biology Research Center, Rappaport Research Institute in the Medical Sciences, The Bruce Rappaport Faculty of Medicine, Technion, Israel Institute of Technology, Haifa 31096, Israel
| | - Michael Simons
- Angiogenesis Research Center and Section of Cardiology, Department of Medicine, Dartmouth Medical School, Lebanon, New Hampshire 03756
| | - Gera Neufeld
- Cancer and Vascular Biology Research Center, Rappaport Research Institute in the Medical Sciences, The Bruce Rappaport Faculty of Medicine, Technion, Israel Institute of Technology, Haifa 31096, Israel
| | - Hellmut G Augustin
- Joint Research Division Vascular Biology of the Medical Faculty Mannheim (CBTM), University of Heidelberg, and the German Cancer Research Center (DKFZ), D-69120 Heidelberg, Germany.
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Sun Q, Nawabi-Ghasimi F, Basile JR. Semaphorins in vascular development and head and neck squamous cell carcinoma-induced angiogenesis. Oral Oncol 2008; 44:523-31. [DOI: 10.1016/j.oraloncology.2007.10.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2007] [Revised: 10/28/2007] [Accepted: 10/10/2007] [Indexed: 01/01/2023]
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Lu L, Zhang L, Xiao Z, Lu S, Yang R, Han ZC. Neuropilin-1 in acute myeloid leukemia: expression and role in proliferation and migration of leukemia cells. Leuk Lymphoma 2008; 49:331-8. [PMID: 18231921 DOI: 10.1080/10428190701809149] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Neuropilin-1 (NRP-1) is a novel receptor of vascular endothelial growth factor (VEGF) and expressed in endothelial cells and tumor cells. The role of NRP-1 in the growth and progression of leukemia is unknown. Here we studied the mRNA expression and effect of NRP-1 in leukemic cells. Our results showed that NRP-1 mRNA was expressed in six of seven leukemic cell lines and primary leukemias derived from all 24 patients with acute myeloid leukemia (AML). Reduced NRP-1 expression by RNA interference led to a decrease of VEGF-mediated mitogenic and migration responses in acute myeloid leukemic cell line HEL. Increased NRP-1 expression was directly correlated with the blast percentage in both peripheral blood and bone marrow of AML patients. Our data demonstrated that a higher level of NRP-1 mRNA was expressed in leukemias and NRP-1 promoted proliferation and chemotaxis of leukemic cells in response to VEGF. Inhibition of NRP-1 functions may provide a new therapeutic strategy for treatment of AML.
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Affiliation(s)
- Lin Lu
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, People's Republic of China
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Waimey KE, Huang PH, Chen M, Cheng HJ. Plexin-A3 and plexin-A4 restrict the migration of sympathetic neurons but not their neural crest precursors. Dev Biol 2008; 315:448-58. [PMID: 18262512 DOI: 10.1016/j.ydbio.2008.01.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2007] [Revised: 12/21/2007] [Accepted: 01/02/2008] [Indexed: 10/22/2022]
Abstract
During development, the semaphorin family of guidance molecules is required for proper formation of the sympathetic nervous system. Plexins are receptors that mediate semaphorin signaling, but how plexins function during sympathetic development is not fully understood. Using phenotypic analyses of mutant mice in vivo, expression pattern studies, and in vitro assays, we show that plexin-A3 and plexin-A4 are essential for normal sympathetic development. This study confirms our previous in vitro findings that the two plexins differentially regulate the guidance of sympathetic axons. In addition, we find that semaphorin signaling through plexin-A3 and plexin-A4 restricts the migration of sympathetic neurons, but these two plexins function redundantly since migration defects are only observed in plexin-A3/-A4 double mutants. Surprisingly, our analysis also indicates that plexin-A3 and plexin-A4 are not required for guiding neural crest precursors prior to reaching the sympathetic anlagen. Immunoprecipitation studies suggest that these two plexins independently mediate secreted semaphorin signaling. Thus, plexin-A3 and plexin-A4 are expressed in newly-differentiated sympathetic neurons, but not their neural crest precursors. They function cooperatively to regulate the migration of sympathetic neurons and then differentially to guide the sympathetic axons.
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Affiliation(s)
- Kathryn E Waimey
- Center for Neuroscience, University of California, Davis, CA 95618, USA
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Hong TM, Chen YL, Wu YY, Yuan A, Chao YC, Chung YC, Wu MH, Yang SC, Pan SH, Shih JY, Chan WK, Yang PC. Targeting neuropilin 1 as an antitumor strategy in lung cancer. Clin Cancer Res 2007; 13:4759-68. [PMID: 17699853 DOI: 10.1158/1078-0432.ccr-07-0001] [Citation(s) in RCA: 142] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
PURPOSE Neuropilin 1 (NRP1) is a mediator of lung branching and angiogenesis in embryonic development and angiogenesis in cancer. The role of NRP1 in cancer progression is not fully elucidated. We investigated the role of NRP1 in cancer invasion and tumor angiogenesis, its signaling pathways, prognostic significance, and therapeutic implications. EXPERIMENTAL DESIGN Sixty patients with non-small cell lung cancer (NSCLC) were studied. NRP1 mRNA expression was measured using real-time quantitative reverse-transcription PCR. NRP1 and cancer cell invasion, angiogenesis, and signaling pathways were studied using NRP1 stimulation by vascular endothelial growth factor 165 (VEGF(165)) and NRP1 inhibition by small interfering RNAs (siRNA), soluble NRP1 (sNRP1), and NRP1-inhibition peptides. The NRP1-inhibition peptides were identified using a phage display peptide library. RESULTS NSCLC patients with high expression of NRP1 had shorter disease-free (P = 0.0162) and overall survival (P = 0.0164; log-rank test). Multivariate analyses showed NRP1 is an independent prognostic factor in overall (HR, 2.37, 95% CI = 1.15 to 4.9, P = 0.0196) and disease-free survival [hazard ratio (HR), 2.38; 95% confidence interval (95% CI), 1.15-4.91; P = 0.0195] of NSCLC patients. Knockdown of NRP1 suppressed cancer cell migration, invasion, filopodia formation, tumorigenesis, angiogenesis, and in vivo metastasis. NRP1 signaling pathways involved VEGF receptor 2 and phosphoinositide-3-kinase (PI3K) and Akt activation. Two potent synthetic anti-NRP1 peptides, DG1 and DG2, which block NRP1 signaling pathways and suppress tumorigenesis, cancer invasion, and angiogenesis, were identified. CONCLUSIONS NRP1 is a cancer invasion and angiogenesis enhancer. NRP1 expression is an independent predictor of cancer relapse and poor survival in NSCLC patients. NRP1 plays a critical role in tumorigenesis, cancer invasion, and angiogenesis through VEGF, PI3K, and Akt pathways. NRP1 may have potential as a new therapeutic target in NSCLC.
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Affiliation(s)
- Tse-Ming Hong
- National Taiwan University Center for Genomic Medicine, College of Medicine, National Taiwan University, Tainan, Taiwan
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Saha B, Hari P, Huilgol D, Tole S. Dual role for LIM-homeodomain gene Lhx2 in the formation of the lateral olfactory tract. J Neurosci 2007; 27:2290-7. [PMID: 17329426 PMCID: PMC2092498 DOI: 10.1523/jneurosci.5571-06.2007] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The development of the olfactory system in vertebrates is a multistep process, in which several regulatory molecules are required at different stages. The development of the olfactory sensory epithelium and its projection to the olfactory bulb are both known to require the LIM-homeodomain transcription factor Lhx2. We examined whether Lhx2 plays a role in the development of the OB itself, as well as its projection to the olfactory cortex. Although there is no morphological OB protuberance in the Lhx2 mutant, mitral cells are normally specified and cluster in a displaced olfactory bulb-like structure (OBLS). The OBLS is not able to pioneer the lateral olfactory tract (LOT) projection in vivo or when provided control (host) telencephalic territory in an in vitro assay. Strikingly, the mutant OBLS is capable of projecting along the LOT if provided with an existing normal LOT in the host explant. This is the first report of a role for a transcription factor expressed in the OB that selectively affects the axon guidance but not the specification of mitral cells. Furthermore, the Lhx2 mutant lateral telencephalon does not support growth of an LOT projection from control OB explants. The defect correlates with the disruption of a cellular mechanism that is thought to be critical for LOT pathfinding: a specialized cell population, the "lot cells," is mislocalized in the Lhx2 mutant. In addition, the expression of Sema6A is aberrantly upregulated. Together, these findings reveal a dual role for Lhx2, in the OB as well as in the lateral telencephalon, for establishing the LOT projection.
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Affiliation(s)
- Bhaskar Saha
- Department of Biological Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai 400 005, India
| | - Padmanabhan Hari
- Department of Biological Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai 400 005, India
| | - Dhananjay Huilgol
- Department of Biological Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai 400 005, India
| | - Shubha Tole
- Department of Biological Sciences, Tata Institute of Fundamental Research, Colaba, Mumbai 400 005, India
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Yamashita N, Uchida Y, Ohshima T, Hirai SI, Nakamura F, Taniguchi M, Mikoshiba K, Honnorat J, Kolattukudy P, Thomasset N, Takei K, Takahashi T, Goshima Y. Collapsin response mediator protein 1 mediates reelin signaling in cortical neuronal migration. J Neurosci 2007; 26:13357-62. [PMID: 17182786 PMCID: PMC6674993 DOI: 10.1523/jneurosci.4276-06.2006] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Collapsin response mediator protein 1 (CRMP1) is one of the CRMP family members that mediates signal transduction of axon guidance molecules. Here, we show evidence that CRMP1 is involved in Reelin (Reln) signaling to regulate neuronal migration in the cerebral cortex. In crmp1-/- mice, radial migration of cortical neurons was retarded. This phenotype was not observed in the sema3A-/- and crmp1+/-;sema3A+/- cortices. However, CRMP1 was colocalized with disabled-1 (Dab1), an adaptor protein in Reln signaling. In the Reln(rl/rl) cortex, CRMP1 and Dab1 were expressed at a higher level, yet tyrosine phosphorylated at a lower level. Loss of crmp1 in a dab1 heterozygous background led to the disruption of hippocampal lamination, a Reeler-like phenotype. In addition to axon guidance, CRMP1 regulates neuronal migration by mediating Reln signaling.
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Affiliation(s)
| | - Yutaka Uchida
- Departments of Molecular Pharmacology and Neurobiology
| | - Toshio Ohshima
- Laboratory for Developmental Neurobiology, Brain Science Institute, The Institute of Physical and Chemical Research, Wako 351-0198, Japan
| | | | | | - Masahiko Taniguchi
- Department of Biochemistry, Cancer Research Institute, Sapporo Medical University, Sapporo 060-8556, Japan
| | - Katsuhiko Mikoshiba
- Laboratory for Developmental Neurobiology, Brain Science Institute, The Institute of Physical and Chemical Research, Wako 351-0198, Japan
| | - Jérôme Honnorat
- Institut National de la Santé et de la Recherche Médicale Unité 433, Institut Federatif des Neurosciences de Lyon, Hôpital Neurologique, F-69003 Lyon, France
| | - Pappachan Kolattukudy
- Biomolecular Science Center, University of Central Florida, Biomolecular Science, Orlando, Florida 32816, and
| | - Nicole Thomasset
- Institut National de la Santé et de la Recherche Médicale Unité 433, Institut Federatif des Neurosciences de Lyon, Hôpital Neurologique, F-69003 Lyon, France
| | - Kohtaro Takei
- Departments of Molecular Pharmacology and Neurobiology
- Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Kawaguchi 332-0012, Japan
| | - Takuya Takahashi
- Physiology and Neuroendocrinology, Yokohama City University Graduate School of Medicine, Yokohama 236-0004, Japan
| | - Yoshio Goshima
- Departments of Molecular Pharmacology and Neurobiology
- Core Research for Evolutional Science and Technology, Japan Science and Technology Agency, Kawaguchi 332-0012, Japan
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68
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Staton CA, Kumar I, Reed MWR, Brown NJ. Neuropilins in physiological and pathological angiogenesis. J Pathol 2007; 212:237-48. [PMID: 17503412 DOI: 10.1002/path.2182] [Citation(s) in RCA: 176] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Neuropilin-1 (Np1) and neuropilin-2 (Np2) are transmembrane glycoproteins with large extracellular domains that interact with both class 3 semaphorins and vascular endothelial growth factor (VEGF), and are involved in the regulation of many physiological pathways, including angiogenesis. The neuropilins also interact directly with the classical receptors for VEGF, VEGF-R1 and -R2, mediating signal transduction. The heart, glomeruli and osteoblasts express both Np1 and Np2, but there is differential expression in the adult vasculature, with Np1 expressed mainly by arterial endothelium, whereas Np2 is only expressed by venous and lymphatic endothelium. Both neuropilins are commonly over-expressed in regions of physiological (wound-healing) and pathological (tumour) angiogenesis, but the signal transduction pathways, neuropilin-mediated gene expression and the definitive role of neuropilins in angiogenic processes are not fully characterized. This review details the current evidence for the role of neuropilins in angiogenesis, and suggests future research directions that may enhance our understanding of the mechanisms of action of this unique family of proteins.
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Affiliation(s)
- C A Staton
- Microcirculation Research Group, Academic Unit of Surgical Oncology, University of Sheffield, Sheffield S10 2JF, UK
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69
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Kolk SM, Pasterkamp RJ. MICAL flavoprotein monooxygenases: structure, function and role in semaphorin signaling. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2007; 600:38-51. [PMID: 17607945 DOI: 10.1007/978-0-387-70956-7_4] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
MICALs (for Molecule Interacting with CasL) form a recently discovered family of evolutionary conserved signal transduction proteins. They contain multiple well-conserved domains known for interactions with the cytoskeleton, cytoskeletal adaptor proteins, and other signaling proteins. In addition to their ability to bind other proteins, MICALs contain a large NADPH-dependent flavoprotein monooxygenase enzymatic domain. Although MICALs have already been implicated in a variety of cellular processes, their function during axonal pathfinding in the Drosophila neuromuscular system has been best characterized. During the establishment of neuromuscular connectivity in the fruit fly, MICAL binds the axon guidance receptor Plexin A and transduces semaphorin-1a-mediated repulsive axon guidance. Intriguingly, mutagenesis and pharmacological inhibitor studies suggest a role for MICAL flavoenzyme redox functions in semaphorin/plexin-mediated axonal pathfinding events. This review summarizes our current understanding of MICALs, with an emphasis on their role in semaphorin signaling.
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Affiliation(s)
- Sharon M Kolk
- Department of Pharmacology and Anatomy, Rudolf Magnus Institute of Neuroscience, University Medical Center Utrecht, Universiteitsweg 100, 3584 CG Utrecht, The Netherlands
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70
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Harel NY, Strittmatter SM. Can regenerating axons recapitulate developmental guidance during recovery from spinal cord injury? Nat Rev Neurosci 2006; 7:603-16. [PMID: 16858389 PMCID: PMC2288666 DOI: 10.1038/nrn1957] [Citation(s) in RCA: 212] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The precise wiring of the adult mammalian CNS originates during a period of stunning growth, guidance and plasticity that occurs during and shortly after development. When injured in adults, this intricate system fails to regenerate. Even when the obstacles to regeneration are cleared, growing adult CNS fibres usually remain misdirected and fail to reform functional connections. Here, we attempt to fill an important niche related to the topics of nervous system development and regeneration. We specifically contrast the difficulties faced by growing fibres within the adult context to the precise circuit-forming capabilities of developing fibres. In addition to focusing on methods to stimulate growth in the adult, we also expand on approaches to recapitulate development itself.
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Affiliation(s)
- Noam Y Harel
- Program in Cellular Neuroscience, Neurodegeneration and Repair, Department of Neurology, Yale University School of Medicine, New Haven, Connecticut 06520, USA
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71
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Abstract
Neuropilins are multifunctional non-tyrosine kinase receptors that bind to class 3 semaphorins and vascular endothelial growth factor. NRP-1 and NRP-2 were first identified for their key role in mediating axonal guidance in the developing nervous system through their interactions with class 3 semaphorins. Growing evidence supports a critical role for these receptors in tumor progression. Neuropilin expression is up-regulated in multiple tumor types, and correlates with tumor progression and prognosis in specific tumors. Neuropilins may indirectly mediate effects on tumor progression by affecting angiogenesis or directly through effects on tumor cells. This article reviews emerging evidence for the role of neuropilins in tumor biology. The therapeutic implications of these data are far-reaching and suggest that neuropilin-targeted interventions may be useful as a component of antineoplastic therapy.
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Affiliation(s)
- Lee M Ellis
- University of Texas M.D. Anderson Cancer Center, Unit 444, P.O. Box 301402, Houston, TX 77230-1402, USA.
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72
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McLennan R, Kulesa PM. In vivo analysis reveals a critical role for neuropilin-1 in cranial neural crest cell migration in chick. Dev Biol 2006; 301:227-39. [PMID: 16959234 DOI: 10.1016/j.ydbio.2006.08.019] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2006] [Revised: 08/02/2006] [Accepted: 08/07/2006] [Indexed: 11/24/2022]
Abstract
The neural crest provides an excellent model system to study invasive cell migration, however it is still unclear how molecular mechanisms direct cells to precise targets in a programmed manner. We investigate the role of a potential guidance factor, neuropilin-1, and use functional knockdown assays, tissue transplantation and in vivo confocal time-lapse imaging to analyze changes in chick cranial neural crest cell migratory patterns. When neuropilin-1 function is knocked down in ovo, neural crest cells fail to fully invade the branchial arches, especially the 2nd branchial arch. Time-lapse imaging shows that neuropilin-1 siRNA transfected neural crest cells stop and collapse filopodia at the 2nd branchial arch entrances, but do not die. This phenotype is cell autonomous. To test the influence of population pressure and local environmental cues in driving neural crest cells to the branchial arches, we isochronically transplanted small subpopulations of DiI-labeled neural crest cells into host embryos ablated of neighboring, premigratory neural crest cells. Time-lapse confocal analysis reveals that the transplanted cells migrate in narrow, directed streams. Interestingly, with the reduction of neuropilin-1 function, neural crest cells still form segmental migratory streams, suggesting that initial neural crest cell migration and invasion of the branchial arches are separable processes.
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Affiliation(s)
- Rebecca McLennan
- Stowers Institute for Medical Research, Kansas City, MO 64110, USA
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73
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Mauti O, Sadhu R, Gemayel J, Gesemann M, Stoeckli ET. Expression patterns of plexins and neuropilins are consistent with cooperative and separate functions during neural development. BMC DEVELOPMENTAL BIOLOGY 2006; 6:32. [PMID: 16846494 PMCID: PMC1543641 DOI: 10.1186/1471-213x-6-32] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/17/2006] [Accepted: 07/17/2006] [Indexed: 01/15/2023]
Abstract
BACKGROUND Plexins are a family of transmembrane proteins that were shown to act as receptors for Semaphorins either alone or in a complex together with Neuropilins. Based on structural criteria Plexins were subdivided into 4 classes, A through D. PlexinAs are mainly thought to act as mediators of repulsive signals in cell migration and axon guidance. Their functional role in vertebrates has been studied almost exclusively in the context of Semaphorin signaling, i.e. as co-receptors for class 3 Semaphorins. Much less is known about Plexins of the other three classes. Despite the fact that Plexins are involved in the formation of neuronal circuits, the temporal changes of their expression patterns during development of the nervous system have not been analyzed in detail. RESULTS Only seven plexins are found in the chicken genome in contrast to mammals, where nine plexins have been identified. Here, we describe the dynamic expression patterns of all known plexin family members in comparison to the neuropilins in the developing chicken spinal cord. CONCLUSION Our in situ hybridization study revealed that the expression patterns of plexins and neuropilins are only partially overlapping, especially during early and intermediate stages of spinal cord development, supporting both cooperative and separate functions of plexins and neuropilins in neural circuit formation.
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Affiliation(s)
- Olivier Mauti
- Institute of Zoology, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Rejina Sadhu
- Institute of Zoology, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Joelle Gemayel
- Brain Research Institute, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Matthias Gesemann
- Brain Research Institute, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
| | - Esther T Stoeckli
- Institute of Zoology, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
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74
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Wang L, Mukhopadhyay D, Xu X. C terminus of RGS-GAIP-interacting protein conveys neuropilin-1-mediated signaling during angiogenesis. FASEB J 2006; 20:1513-5. [PMID: 16754745 DOI: 10.1096/fj.05-5504fje] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Initially, it was thought that there was no intracellular signaling mediated by NRP-1 alone in response to its ligands. However, the emerging data from our group as well as others suggest that the signaling through NRP-1 actually promotes angiogenesis and is mediated through its C-terminal domain and downstream molecules such as phosphoinositide 3-kinase. Hence, understanding the signal transduction pathways mediated by NRP-1 and identification of its downstream molecules are of importance. By using both in vivo zebrafish model and in vitro tissue culture system, we have shown that the C-terminal three amino acids of NRP-1 (SEA-COOH) are required for NRP-1-mediated angiogenesis. Furthermore, knocking down of RGS-GAIP-interacting protein C terminus (GIPC) in zebrafish, which is associated with C-terminal domain of NRP-1, exhibits similar vasculature phenotypes to those from NRP-1 null. Specific and effective silencing of GIPC in vascular endothelium results in inhibition of NRP-1-mediated migration. In both cases as described, PDZ domain of GIPC is responsible for its function. Taken together, our data suggest a novel role of GIPC in angiogenesis and vessel formation and also support our hypothesis that NRP-1 can facilitate downstream signaling to promote angiogenesis through GIPC.
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Affiliation(s)
- Ling Wang
- Department Biochemistry and Molecular Biology, Gugg 1401A, Mayo Clinic College of Medicine, 200 First St. SW, Rochester, Minnesota 55905, USA
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75
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Hermanson E, Borgius L, Bergsland M, Joodmardi E, Perlmann T. Neuropilin1 is a direct downstream target of Nurr1 in the developing brain stem. J Neurochem 2006; 97:1403-11. [PMID: 16638018 DOI: 10.1111/j.1471-4159.2006.03829.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The orphan nuclear receptor Nurr1 is expressed in the developing and adult central nervous system. Previous studies have shown that Nurr1 is essential for the generation of midbrain dopamine neurons. Furthermore, Nurr1 is critical for respiratory functions associated with the brain stem. Very few Nurr1 regulated genes have been identified and it remains unclear how Nurr1 influences the function and development of neurons. To identify novel Nurr1 target genes we have searched for regulated genes in the dopaminergic MN9D cell line. These experiments identified Neuropilin-1 (Nrp1), a receptor protein involved in axon guidance and angiogenesis, as a novel Nurr1 target gene. Nrp1 expression was rapidly up-regulated by Nurr1 in MN9D cells and in situ hybridization analysis showed that Nrp1 was coexpressed with Nurr1 in the brain stem dorsal motor nucleus. Importantly, Nrp1 expression was down-regulated in this area in Nurr1 null mice. Moreover, two functional Nurr1 binding sites were identified in the Nrp1 promoter and Nurr1 was found to be recruited to these sites in MN9D cells, further supporting that Nrp1 is a direct downstream target of Nurr1. Taken together, our findings suggest that Nurr1 might influence the processes of axon guidance and/or angiogenesis via the regulation of Nrp1 expression.
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Affiliation(s)
- Elisabet Hermanson
- Ludwig Institute for Cancer Research, Stockholm Branch, Stockholm, Sweden
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76
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Abstract
Increased uterine vascular permeability and angiogenesis are hallmarks of implantation and placentation. These events are profoundly influenced by vascular endothelial growth factor (VEGF). Although VEGF and its receptor Flk-1 are primarily important for uterine vascular permeability and angiogenesis before and during the attachment phase of the implantation process, VEGF together with the angiopoietins and their receptor Tie-2 directs angiogenesis during decidualization after implantation. Uterine expression of HIF and ARNT follows the localization of VEGF expression with increasing angiogenesis during the postimplantation period, although their expression does not correlate with VEGF expression during the pre-implantation period. Upstream of VEGF, estrogen promotes uterine vascular permeability but inhibits angiogenesis, whereas progesterone stimulates angiogenesis with little effect on vascular permeability. Furthermore, COX-2-derived prostaglandins participate in uterine vascular permeability and angiogenesis during implantation and decidualization. (Reprod Med Biol 2006; 5: 81-86).
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77
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Abstract
Increased uterine vascular permeability and angiogenesis are hallmarks of implantation and placentation. These events are profoundly influenced by vascular endothelial growth factor (VEGF). Although VEGF and its receptor Flk-1 are primarily important for uterine vascular permeability and angiogenesis before and during the attachment phase of the implantation process, VEGF together with the angiopoietins and their receptor Tie-2 directs angiogenesis during decidualization after implantation. Uterine expression of HIF and ARNT follows the localization of VEGF expression with increasing angiogenesis during the postimplantation period, although their expression does not correlate with VEGF expression during the pre-implantation period. Upstream of VEGF, estrogen promotes uterine vascular permeability but inhibits angiogenesis, whereas progesterone stimulates angiogenesis with little effect on vascular permeability. Furthermore, COX-2-derived prostaglandins participate in uterine vascular permeability and angiogenesis during implantation and decidualization. (Reprod Med Biol 2006; 5: 81-86).
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Affiliation(s)
- Hiromichi Matsumoto
- Laboratory of Animal Reproduction, Graduate School of Agricultural Science, Tohoku University, Sendai and.,Department of Animal Breeding and Reproduction, Faculty of Agriculture, Utsunomiya University, Utsunomiya, Tochigi, Japan
| | - Eimei Sato
- Laboratory of Animal Reproduction, Graduate School of Agricultural Science, Tohoku University, Sendai and
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78
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Vacca A, Scavelli C, Serini G, Di Pietro G, Cirulli T, Merchionne F, Ribatti D, Bussolino F, Guidolin D, Piaggio G, Bacigalupo A, Dammacco F. Loss of inhibitory semaphorin 3A (SEMA3A) autocrine loops in bone marrow endothelial cells of patients with multiple myeloma. Blood 2006; 108:1661-7. [PMID: 16684957 DOI: 10.1182/blood-2006-04-014563] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Vascular endothelial growth factor165 (VEGF165) and semaphorin3A (SEMA3A) elicit pro- and antiangiogenic signals respectively in endothelial cells (ECs) by binding to their receptors VEGFR-2, neuropilin-1 (NRP1), and plexin-A1. Here we show that the VEGF165-driven angiogenic potential of multiple myeloma (MM) ECs is significantly higher than that of monoclonal gammopathy of undetermined significance (MGUS) ECs (MGECs) and human umbilical vein (HUV) ECs. This is probably due to a constitutive imbalance of endogenous VEGF165/SEMA3A ratio, which leans on VEGF165 in MMECs but on SEMA3A in MGECs and HUVECs. Exogenous VEGF165 induces SEMA3A expression in MGECs and HUVECs, but not in MMECs. Moreover, by counteracting VEGF165 activity as efficiently as an anti-VEGFR-2 antibody, exogenous SEMA3A restrains the over-angiogenic potential of MMECs. Our data indicate that loss of endothelial SEMA3A in favor of VEGF165 could be responsible for the angiogenic switch from MGUS to MM.
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Affiliation(s)
- Angelo Vacca
- Department of Internal Medicine and Clinical Oncology, University of Bari Medical School, Bari, Italy.
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79
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Byrne AM, Bouchier-Hayes DJ, Harmey JH. Angiogenic and cell survival functions of vascular endothelial growth factor (VEGF). J Cell Mol Med 2006; 9:777-94. [PMID: 16364190 PMCID: PMC6740098 DOI: 10.1111/j.1582-4934.2005.tb00379.x] [Citation(s) in RCA: 503] [Impact Index Per Article: 27.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Vascular endothelial growth factor (VEGF) was originally identified as an endothelial cell specific growth factor stimulating angiogenesis and vascular permeability. Some family members, VEGF C and D, are specifically involved in lymphangiogenesis. It now appears that VEGF also has autocrine functions acting as a survival factor for tumour cells protecting them from stresses such as hypoxia, chemotherapy and radiotherapy. The mechanisms of action of VEGF are still being investigated with emerging insights into overlapping pathways and cross-talk between other receptors such as the neuropilins which were not previously associated with angiogenesis. VEGF plays an important role in embryonic development and angiogenesis during wound healing and menstrual cycle in the healthy adult. VEGF is also important in a number of both malignant and non-malignant pathologies. As it plays a limited role in normal human physiology, VEGF is an attractive therapeutic target in diseases where VEGF plays a key role. It was originally thought that in pathological conditions such as cancer, VEGF functioned solely as an angiogenic factor, stimulating new vessel formation and increasing vascular permeability. It has since emerged it plays a multifunctional role where it can also have autocrine pro-survival effects and contribute to tumour cell chemoresistance. In this review we discuss the established role of VEGF in angiogenesis and the underlying mechanisms. We discuss its role as a survival factor and mechanisms whereby angiogenesis inhibition improves efficacy of chemotherapy regimes. Finally, we discuss the therapeutic implications of targeting angiogenesis and VEGF receptors, particularly in cancer therapy.
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Affiliation(s)
- Anne Marie Byrne
- Royal College of Surgeons in Ireland, Department of Surgery, Education and Research Centre, Beaumont Hospital, Dublin
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80
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Hirata T, Nakazawa M, Yoshihara SI, Miyachi H, Kitamura K, Yoshihara Y, Hibi M. Zinc-finger gene Fez in the olfactory sensory neurons regulates development of the olfactory bulb non-cell-autonomously. Development 2006; 133:1433-43. [PMID: 16540508 DOI: 10.1242/dev.02329] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Fez is a zinc-finger gene encoding a transcriptional repressor that is expressed in the olfactory epithelium, hypothalamus, ventrolateral pallium and prethalamus at mid-gestation. To reveal its function, we generated Fez-deficient mice. The Fez-deficient mice showed several abnormalities in the olfactory system: (1) impaired axonal projection of the olfactory sensory neurons; (2) reduced size of the olfactory bulb; (3) abnormal layer formation in the olfactory bulb; and (4) aberrant rostral migration of the interneuron progenitors. Fez was not expressed in the projection neurons, interneurons or interneuron progenitors. Transgene-mediated expression of Fez in olfactory sensory neurons significantly rescued the abnormalities in olfactory axon projection and in the morphogenesis of the olfactory bulb in Fez-knockout mice. Thus, Fez is cell-autonomously required for the axon termination of olfactory sensory neurons, and Fez non-cell-autonomously controls layer formation and interneuron development in the olfactory bulb. These findings suggest that signals from olfactory sensory neurons contribute to the proper formation of the olfactory bulb.
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Affiliation(s)
- Tsutomu Hirata
- Laboratory for Vertebrate Axis Formation, Center for Developmental Biology, RIKEN, Kobe 650-0047, Japan
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81
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Suto F, Ito K, Uemura M, Shimizu M, Shinkawa Y, Sanbo M, Shinoda T, Tsuboi M, Takashima S, Yagi T, Fujisawa H. Plexin-a4 mediates axon-repulsive activities of both secreted and transmembrane semaphorins and plays roles in nerve fiber guidance. J Neurosci 2006; 25:3628-37. [PMID: 15814794 PMCID: PMC6725384 DOI: 10.1523/jneurosci.4480-04.2005] [Citation(s) in RCA: 167] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
It has been proposed that four members of the plexin A subfamily (plexin-As; plexin-A1, -A2, -A3, and -A4) and two neuropilins (neuropilin-1 and neuropilin-2) form complexes and serve as receptors for class 3 secreted semaphorins (Semas), potent neural chemorepellents. The roles of given plexin-As in semaphorin signaling and axon guidance, however, are mostly unknown. Here, to elucidate functions of plexin-A4 in semaphorin signaling and axon guidance events in vivo, we generated plexin-A4 null mutant mice by targeted disruption of the plexin-A4 gene. Plexin-A4 mutant mice were defective in the trajectory and projection of peripheral sensory axons and sympathetic ganglion (SG) axons and the formation of the anterior commissure and the barrels. The defects in peripheral sensory and SG axons were fundamentally related to those of neuropilin-1 or Sema3A mutant embryos reported but were more moderate than the phenotype in these mutants. The growth cone collapse assay showed that dorsal root ganglion axons and SG axons of plexin-A4 mutant embryos partially lost their responsiveness to Sema3A. These results suggest that plexin-A4 plays roles in the propagation of Sema3A activities and regulation of axon guidance and that other members of the plexin-A subfamily are also involved in the propagation of Sema3A activities. Plexin-A4-deficient SG axons did not lose their responsiveness to Sema3F, suggesting that plexin-A4 serves as a Sema3A-specific receptor, at least in SG axons. In addition, the present study showed that plexin-A4 bound class 6 transmembrane semaphorins, Sema6A and Sema6B, and mediated their axon-repulsive activities, independently of neuropilin-1. Our results imply that plexin-A4 mediates multiple semaphorin signals and regulates axon guidance in vivo.
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MESH Headings
- Animals
- Animals, Newborn
- Axons/physiology
- Cell Adhesion Molecules, Neuronal/metabolism
- Cells, Cultured
- Cloning, Molecular/methods
- Contactin 2
- Dose-Response Relationship, Drug
- Electron Transport Complex IV/metabolism
- Embryo, Mammalian
- Ganglia, Spinal/cytology
- Ganglia, Spinal/metabolism
- Gene Expression Regulation, Developmental/genetics
- Immunohistochemistry/methods
- In Situ Hybridization/methods
- Mice
- Mice, Knockout
- Nerve Fibers/physiology
- Nerve Tissue Proteins/deficiency
- Nerve Tissue Proteins/physiology
- Neurites/metabolism
- Neurons/cytology
- Neurons/metabolism
- Neuropilin-1/metabolism
- Prosencephalon/embryology
- Prosencephalon/metabolism
- Receptors, Cell Surface/deficiency
- Receptors, Cell Surface/physiology
- Recombinant Proteins/metabolism
- Semaphorins/metabolism
- Semaphorins/pharmacokinetics
- Sympathetic Nervous System/metabolism
- Tubulin/metabolism
- Tyrosine 3-Monooxygenase/metabolism
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Affiliation(s)
- Fumikazu Suto
- Division of Developmental Genetics, National Institute of Genetics, Mishima 411-8540, Japan
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82
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McCloskey DP, Croll SD, Scharfman HE. Depression of synaptic transmission by vascular endothelial growth factor in adult rat hippocampus and evidence for increased efficacy after chronic seizures. J Neurosci 2006; 25:8889-97. [PMID: 16192378 PMCID: PMC1415170 DOI: 10.1523/jneurosci.2577-05.2005] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
In addition to its potent effects on vasculature, it has become clear that vascular endothelial growth factor (VEGF) has effects on both neurons and glia, and recent studies suggest that it can be neuroprotective. To determine potential mechanisms underlying this neuroprotection, recombinant human VEGF was bath applied to adult rat hippocampal slices, and both extracellular and intracellular recordings were used to examine intrinsic properties and synaptic responses of hippocampal principal neurons. Initial studies in area CA1 showed that VEGF significantly reduced the amplitude of responses elicited by Schaffer collateral stimulation, without influencing membrane properties. Similar effects occurred in CA3 pyramidal cells and dentate gyrus granule cells when their major glutamatergic afferents were stimulated. Because VEGF expression is increased after seizures, effects of VEGF were also examined in rats with recurrent spontaneous seizures. VEGF reduced spontaneous discharges in slices from these rats but had surprisingly little effect on epileptiform discharges produced by disinhibition of slices from control rats. These results demonstrate a previously unknown effect of VEGF on neuronal activity and also demonstrate a remarkable potency in the epileptic brain. Based on this, we suggest that VEGF or VEGF-related targets could provide useful endpoints to direct novel therapeutic strategies for epilepsy.
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Affiliation(s)
- Daniel P McCloskey
- Center for Neural Recovery and Rehabilitation Research, Helen Hayes Hospital, West Haverstraw, New York 10993, USA.
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83
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Abstract
The precise coordination of the many events in nervous system development is absolutely critical for the correct establishment of functional circuits. The postganglionic sympathetic neuron has been an amenable model for studying peripheral nervous system formation. Factors that control several developmental events, including multiple stages of axon extension, neuron survival and death, dendritogenesis, synaptogenesis, and establishment of functional diversity, have been identified in this neuron type. This knowledge allows us to integrate the various intricate processes involved in the formation of a functional sympathetic nervous system and thereby create a paradigm for understanding neuronal development in general.
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Affiliation(s)
- Natalia O Glebova
- Department of Neuroscience, Howard Hughes Medical Institute, The Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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84
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Basile JR, Afkhami T, Gutkind JS. Semaphorin 4D/plexin-B1 induces endothelial cell migration through the activation of PYK2, Src, and the phosphatidylinositol 3-kinase-Akt pathway. Mol Cell Biol 2005; 25:6889-98. [PMID: 16055703 PMCID: PMC1190270 DOI: 10.1128/mcb.25.16.6889-6898.2005] [Citation(s) in RCA: 116] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Semaphorins are cell surface and secreted proteins that provide axonal guidance in neuronal tissues and regulate cell motility in many cell types. They act by binding a family of transmembrane receptors known as plexins, which belong to the c-Met family of scatter factor receptors but lack an intrinsic tyrosine kinase domain. Interestingly, we have recently shown that Plexin-B1 is highly expressed in endothelial cells and that its activation by Semaphorin 4D elicits a potent proangiogenic response (J. R. Basile, A. Barac, T. Zhu, K. L. Guan, and J. S. Gutkind, Cancer Res. 64:5212-5224, 2004). In searches for the underlying molecular mechanism, we observed that Semaphorin 4D-stimulated endothelial cell migration requires the activation of the phosphatidylinositol 3-kinase (PI3K)-Akt pathway. Surprisingly, we found that Plexin-B1 stimulates PI3K-Akt through the activation of an intracellular tyrosine kinase cascade that involves the sequential activation of PYK2 and Src. This results in the tyrosine phosphorylation of Plexin-B1, the rapid recruitment of a multimeric signaling complex that includes PYK2, Src, and PI3K to Plexin-B1 and the activation of Akt. These findings suggest that Plexin-B1 may achieve its numerous physiological functions through the direct activation of intracellular tyrosine kinase cascades.
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Affiliation(s)
- John R Basile
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD 20892, USA.
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85
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Agudo M, Robinson M, Cafferty W, Bradbury EJ, Kilkenny C, Hunt SP, McMahon SB. Regulation of neuropilin 1 by spinal cord injury in adult rats. Mol Cell Neurosci 2005; 28:475-84. [PMID: 15737738 DOI: 10.1016/j.mcn.2004.10.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2004] [Revised: 10/05/2004] [Accepted: 10/19/2004] [Indexed: 11/16/2022] Open
Abstract
Using RT-PCR, in situ hybridization, Western blotting, and immunofluorescence, we have analyzed the expression of neuropilin 1 (Np1) in two models of spinal cord injury (spinal cord hemisection and dorsal column crush) and following dorsal root rhizotomy in adult rats. Our results show that Np1 RNA and protein are up-regulated in the spinal cord after all these lesions but remain unaltered in the adjacent dorsal root ganglia. In control animals, Np1 levels in the spinal cord are low and appear to be localized mainly in blood vessels, motoneurons, and in the superficial layers of the dorsal horn. After DCC and rhizotomy, Np1 is expressed de novo around the injury and in the deafferentated dorsal horn, respectively, mainly by OX42-positive microglial cells. Both lesions affect the sensory projections, and interestingly a consistent increase of Np1 signal is additionally seen in the dorsal horn where these projections terminate. Unexpectedly, this increase is bilateral after unilateral rhizotomy.
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Affiliation(s)
- Marta Agudo
- Neuro Restoration CARD, Wolfson Centre Guy's Campus, King's College London, London Bridge, London SE1 1UL, UK.
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86
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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: 9.1] [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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87
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Pascual M, Pozas E, Soriano E. Role of class 3 semaphorins in the development and maturation of the septohippocampal pathway. Hippocampus 2005; 15:184-202. [PMID: 15386596 DOI: 10.1002/hipo.20040] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
In examining the role of Class 3 secreted semaphorins in the prenatal and postnatal development of the septohippocampal pathway, we found that embryonic (E14-E16) septal axons were repelled by the cingulate cortex and the striatum. We also found that the hippocampus exerts chemorepulsion on dorsolateral septal fibers, but not on fibers arising in the medial septum/diagonal band complex, which is the source of septohippocampal axons. These data indicate that endogenous chemorepellents prevent the growth of septal axons in nonappropriate brain areas and direct septohippocampal fibers to the target hippocampus. The embryonic septum expressed np-1 and np-2 mRNAs, and the striatum and cerebral cortex expressed sema 3A and sema 3F. Experiments with recombinant semaphorins showed that Sema 3A and 3F, but not Sema 3C or 3E, induce chemorepulsion of septal axons. Sema 3A and 3F also induce growth cone collapse of septal axons. This indicates that these factors are endogenous cues for the early guidance of septohippocampal fibers, including cholinergic and gamma-aminobutyric acid (GABA)ergic axons, during the embryonic stages. During postnatal stages, when target cell selection and synaptogenesis take place, np-1 and np-2 were expressed by septohippocampal neurons at all ages tested. In the target hippocampus, pyramidal and granule cells expressed sema 3E and sema 3A, whereas most interneurons expressed sema 3C, but few expressed sema 3E or 3A. Combined tracing and expression studies showed that GABAergic septohippocampal fibers terminated preferentially onto sema 3C-positive interneurons. In contrast, cholinergic septohippocampal fibers terminated onto sema 3E and sema 3A-expressing pyramidal and granule cells. The data suggest that Class 3 secreted semaphorins are involved in postnatal development. Moreover, because GABAergic and cholinergic axons terminate onto neurons expressing distinct, but overlapping, patterns of semaphorin expression, semaphorin functions may be regulated by different signaling mechanisms at postnatal stages.
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Affiliation(s)
- Marta Pascual
- Department of Cell Biology, Faculty of Biology, University of Barcelona/Barcelona Science Park, Barcelona, Spain
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88
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Cohen S, Funkelstein L, Livet J, Rougon G, Henderson CE, Castellani V, Mann F. A semaphorin code defines subpopulations of spinal motor neurons during mouse development. Eur J Neurosci 2005; 21:1767-76. [PMID: 15869472 DOI: 10.1111/j.1460-9568.2005.04021.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Abstract In the spinal cord, motor neurons (MNs) with similar muscle targets and sensory inputs are grouped together into motor pools. To date, relatively little is known about the molecular mechanisms that control the establishment of pool-specific circuitry. Semaphorins, a large family of secreted and cell surface proteins, are important mediators of developmental processes such as axon guidance and cell migration. Here, we used mRNA in situ hybridization to study the expression patterns of semaphorins and their receptors, neuropilins and plexins, in the embryonic mouse spinal cord. Our data show that semaphorins and their receptors are differentially expressed in MNs that lie in distinct locations within the spinal cord. Furthermore, we report a combinatorial expression of class 3 (secreted) semaphorins and their receptors that characterizes distinct motor pools within the brachial and lumbar spinal cord. Finally, we found that a secreted semaphorin, Sema3A, elicits differential collapse responses in topologically distinct subpopulations of spinal MNs. These findings lead us to propose that semaphorins and their receptors might play important roles in the sorting of motor pools and the patterning of their afferent and efferent projections.
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Affiliation(s)
- Samia Cohen
- INSERM UMR 623, Developmental Biology Institute of Marseille, CNRS-- INSERM--Univ--Mediterranee, Campus de Luminy, Case 907, 13288 Marseille cedex 09, France
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89
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Gerhardt H, Ruhrberg C, Abramsson A, Fujisawa H, Shima D, Betsholtz C. Neuropilin-1 is required for endothelial tip cell guidance in the developing central nervous system. Dev Dyn 2005; 231:503-9. [PMID: 15376331 DOI: 10.1002/dvdy.20148] [Citation(s) in RCA: 198] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Recent evidence indicates that sprouting angiogenesis in the central nervous system (CNS) is a guided process similar to the guidance of axons and insect tracheal tubes. Specialized tip cells of vessel sprouts navigate in response to local depots or gradients of vascular endothelial growth factor (VEGF-A). Neuropilin-1 (Nrp-1) is a transmembrane receptor with a repulsive function in axon guidance. Nrp-1 also binds the VEGF-A splice isoform VEGF165, stimulates angiogenesis, and is necessary for vascular development in the mouse. However, the morphogenetic events controlled by Nrp-1 in angiogenesis have not been defined. Here, we analyzed endothelial tip cell guidance in the CNS of Nrp-1-deficient mice. We focused our attention on the developing hindbrain, which is normally vascularized in a stereotyped manner. Initially, angiogenic sprouts extend along radial glia from the pial surface toward the ventricles, but in the subventricular zone (SVZ), they leave the radial path, turn laterally, and fuse to form a capillary plexus. Radial sprout elongation correlated with tip cell filopodia extensions along nestin-positive radial glial processes, but in the SVZ, the tip cell filopodia also extended perpendicular to the glial tracks and made contact with filopodia of the neighboring sprouts. In Nrp-1-deficient mice, the tip cell filopodia remained associated with the radial glia in the SVZ, which correlated with a failure of sprout turning and elongation across this region. As a result, the sprouts remained blind-ended forming glomeruloid tufts in the SVZ. These observations suggest that Nrp-1 plays an important role in allowing the endothelial tip cell filopodia to switch substrate and protrude in a new direction at a specific location in the developing brain.
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MESH Headings
- Animals
- Antibodies, Monoclonal/metabolism
- Central Nervous System/cytology
- Central Nervous System/metabolism
- Endothelial Cells/metabolism
- Endothelium, Vascular/cytology
- Endothelium, Vascular/growth & development
- Endothelium, Vascular/metabolism
- Imaging, Three-Dimensional
- Intermediate Filament Proteins/metabolism
- Mice
- Mice, Knockout
- Microscopy, Confocal
- Models, Biological
- Neovascularization, Physiologic/drug effects
- Neovascularization, Physiologic/physiology
- Nerve Tissue Proteins/metabolism
- Nestin
- Neuroglia/cytology
- Neuroglia/metabolism
- Neuropilin-1/physiology
- Pseudopodia/drug effects
- Pseudopodia/metabolism
- Rhombencephalon/cytology
- Rhombencephalon/metabolism
- Vascular Endothelial Growth Factor A/metabolism
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Affiliation(s)
- Holger Gerhardt
- Department of Medical Biochemistry, University of Göteborg, Medicinaregatan 9A, Box 440, SE 405-30 Göteborg, Sweden.
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90
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Cackowski FC, Xu L, Hu B, Cheng SY. Identification of two novel alternatively spliced Neuropilin-1 isoforms. Genomics 2005; 84:82-94. [PMID: 15203206 PMCID: PMC2868064 DOI: 10.1016/j.ygeno.2004.02.001] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2003] [Accepted: 02/02/2004] [Indexed: 01/13/2023]
Abstract
Neuropilin-1 (NRP1) is a coreceptor to a tyrosine kinase receptor for both the vascular endothelial growth factor (VEGF) family and semaphorin (Sema) family members. NRP1 plays versatile roles in angiogenesis, axon guidance, cell survival, migration, and invasion. NRP1 contains three distinct extracellular domains, a1a2, b1b2, and c. We report here the identification of two novel soluble human NRP1 isoforms, which we named sIIINRP1 and sIVNRP1. These soluble NRP1 isoforms were generated by alternative splicing of the NRP1 gene, a common regulatory mechanism occurring in cell surface receptor families. Both sIIINRP1 and sIVNRP1 contain a1a2 and b1b2 domains, but no c domain, and the rest of the NRP1 sequence. Additionally, sIIINRP1 is missing 48 amino acids within the C-terminus of the b2 domain. Both sIIINRP1 and sIVNRP1 are expressed in human cancerous and normal tissues. These molecules are capable of binding to VEGF165 and Sema3A. Furthermore, recombinant sIIINRP1 and sIVNRP1 proteins inhibit NRP1-mediated MDA-MB-231 breast cancer cell migration. These results indicate the multiple levels of regulation in NRP1 function and suggest that these two novel NRP1 isoforms are useful antagonists for NRP1-mediated cellular activities.
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Affiliation(s)
- Frank C. Cackowski
- Cancer Institute and Department of Pathology, University of Pittsburgh, Research Pavilion at Hillman Cancer Center, Room 2.19, 5117 Centre Avenue, Pittsburgh, PA 15213-1863, USA
- Department of Biological Sciences, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213, USA
| | - Li Xu
- Cancer Institute and Department of Pathology, University of Pittsburgh, Research Pavilion at Hillman Cancer Center, Room 2.19, 5117 Centre Avenue, Pittsburgh, PA 15213-1863, USA
| | - Bo Hu
- Cancer Institute and Department of Pathology, University of Pittsburgh, Research Pavilion at Hillman Cancer Center, Room 2.19, 5117 Centre Avenue, Pittsburgh, PA 15213-1863, USA
- Department of Medicine, University of Pittsburgh, Research Pavilion at Hillman Cancer Center, Room 2.19, 5117 Centre Avenue, Pittsburgh, PA 15213-1863, USA
- Corresponding authors. Fax: (412) 623-4840. (B. Hu), (S.-Y. Cheng)
| | - Shi-Yuan Cheng
- Cancer Institute and Department of Pathology, University of Pittsburgh, Research Pavilion at Hillman Cancer Center, Room 2.19, 5117 Centre Avenue, Pittsburgh, PA 15213-1863, USA
- Corresponding authors. Fax: (412) 623-4840. (B. Hu), (S.-Y. Cheng)
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91
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Inaki K, Nishimura S, Nakashiba T, Itohara S, Yoshihara Y. Laminar organization of the developing lateral olfactory tract revealed by differential expression of cell recognition molecules. J Comp Neurol 2005; 479:243-56. [PMID: 15457507 DOI: 10.1002/cne.20270] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The projection neurons in the olfactory bulb (mitral and tufted cells) send axons through the lateral olfactory tract (LOT) onto several structures of the olfactory cortex. However, little is known of the molecular and cellular mechanisms underlying establishment of functional connectivity from the bulb to the cortex. Here, we investigated the developmental process of LOT formation by observing expression patterns of cell recognition molecules in embryonic mice. We immunohistochemically identified a dozen molecules expressed in the developing LOT and some of them were localized to subsets of mitral cell axons. Combinatorial immunostaining for these molecules revealed that the developing LOT consists of three laminas: superficial, middle, and deep. Detailed immunohistochemical, in situ hybridization, and 5-bromodeoxyuridine labeling analyses suggested that the laminar organization reflects: 1) the segregated pathways from the accessory and main olfactory bulbs, and 2) the different maturity of mitral cell axons. Mitral cell axons of the accessory olfactory bulb were localized to the deep lamina, segregated from those of the main olfactory bulb. In the main olfactory pathway, axons of mature mitral cells, whose somata is located in the apical sublayer of the mitral cell layer, were localized to the middle lamina within LOT, while those of immature mitral cells that located in the basal sublayer were complementarily localized to the superficial lamina. These results suggest that newly generated immature axons are added to the most superficial lamina of LOT successively, leading to the formation of piled laminas with different maturational stages of the mitral cell axons.
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Affiliation(s)
- Koichiro Inaki
- Laboratory for Neurobiology of Synapse, RIKEN Brain Science Institute, Saitama 351-0198, Japan
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92
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Yang J, Houk B, Shah J, Hauser KF, Luo Y, Smith G, Schauwecker E, Barnes GN. Genetic background regulates semaphorin gene expression and epileptogenesis in mouse brain after kainic acid status epilepticus. Neuroscience 2005; 131:853-69. [PMID: 15749340 DOI: 10.1016/j.neuroscience.2004.09.064] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/27/2004] [Indexed: 10/25/2022]
Abstract
The host response to neural injury, which can include axonal sprouting and synaptic reorganization is likely to be under tight genetic regulatory control at the level of the genome and may be implicated in epileptogenesis. Despite its importance, however, the molecular basis of synaptic reorganization is unclear. We have studied the development of synaptic reorganization, semaphorin gene expression, and epileptogenesis in hippocampus of epileptogenic sensitive (FVB/NJ) and epileptogenic resistant (C57BL/6J) mice (i.e. distinct genetic backgrounds) after kainic acid-induced status epilepticus. Our results support the hypothesis that disruption of transcriptional regulation of axon guidance genes leads to a differential loss of tonic neuropilin-2 dependent activation of semaphorin 3F receptors on hippocampal neurons on distinct genetic backgrounds. This results in rearranged synaptic circuitry and thus promotes epileptogenesis. These findings may define biologic principles underlying the role of semaphorin signaling which may broadly apply to other systems undergoing neural regeneration.
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Affiliation(s)
- J Yang
- Department of Neurology, University of Kentucky College of Medicine, Lexington, KY, USA
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93
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Abstract
Neuropilins and group A plexins are components of receptor complexes for class 3 semaphorins, gradients of which help to guide migration of neural progenitor cells and axonal growth cones during development. We demonstrated previously that neuropilins and class 3 semaphorins are induced in sciatic nerve by crush or transection. We now report that in cultured rat Schwann cells, expression of mRNA encoding neuropilin-2 (NRP2) and plexin-A3 (PlexA3), proteins involved in semaphorin-3F (Sema3F) signal transduction, is diminished markedly by forskolin, an adenylate cyclase activator that, like axonal contact, induces Schwann cell synthesis of myelin lipids and proteins. Interestingly, Schwann cell expression of mRNA encoding NRP1, which participates in Sema3A signaling, is not downregulated by forskolin. Antibodies that recognize ectodomains of NRP2 but not control antibodies prevented cultured Schwann cells from aligning in parallel and forming columns. These results are consistent with the view that in nerves undergoing Wallerian degeneration, Schwann cell NRP2 facilitates assembly of Schwann cells into the tubular aggregates (bands of Büngner) that guide regenerating axons.
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MESH Headings
- Animals
- Animals, Newborn
- Blotting, Western/methods
- Cells, Cultured
- Colforsin/pharmacology
- Dose-Response Relationship, Drug
- Fibroblasts/drug effects
- Fibroblasts/physiology
- Gene Expression Regulation, Developmental/drug effects
- Gene Expression Regulation, Developmental/physiology
- Nerve Tissue Proteins/genetics
- Nerve Tissue Proteins/metabolism
- Neuropilin-1/genetics
- Neuropilin-1/metabolism
- Neuropilin-2/physiology
- RNA, Messenger/metabolism
- Rats
- Rats, Inbred Lew
- Receptor, Nerve Growth Factor
- Receptors, Cell Surface/genetics
- Receptors, Cell Surface/metabolism
- Receptors, Nerve Growth Factor/metabolism
- Reverse Transcriptase Polymerase Chain Reaction/methods
- Schwann Cells/drug effects
- Schwann Cells/metabolism
- Sciatic Nerve/cytology
- Semaphorin-3A/genetics
- Semaphorin-3A/metabolism
- Time Factors
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Affiliation(s)
- J Ara
- Neurology Research, the Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, USA
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94
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Kettunen P, Løes S, Furmanek T, Fjeld K, Kvinnsland IH, Behar O, Yagi T, Fujisawa H, Vainio S, Taniguchi M, Luukko K. Coordination of trigeminal axon navigation and patterning with tooth organ formation: epithelial-mesenchymal interactions, and epithelial Wnt4 and Tgfbeta1 regulate semaphorin 3a expression in the dental mesenchyme. Development 2004; 132:323-34. [PMID: 15604101 DOI: 10.1242/dev.01541] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
During development, trigeminal nerve fibers navigate and establish their axonal projections to the developing tooth in a highly spatiotemporally controlled manner. By analyzing Sema3a and its receptor Npn1 knockout mouse embryos, we found that Sema3a regulates dental trigeminal axon navigation and patterning, as well as the timing of the first mandibular molar innervation, and that the effects of Sema3a appear to be mediated by Npn1 present in the axons. By performing tissue recombinant experiments and analyzing the effects of signaling molecules, we found that early oral and dental epithelia, which instruct tooth formation, and epithelial Wnt4 induce Sema3a expression in the presumptive dental mesenchyme before the arrival of the first dental nerve fibers. Later, at the bud stage, epithelial Wnt4 and Tgfbeta1 regulate Sema3a expression in the dental mesenchyme. In addition, Wnt4 stimulates mesenchymal expression of Msx1 transcription factor, which is essential for tooth formation, and Tgfbeta1 proliferation of the dental mesenchymal cells. Thus, epithelial-mesenchymal interactions control Sema3a expression and may coordinate axon navigation and patterning with tooth formation. Moreover, our results suggest that the odontogenic epithelium possesses the instructive information to control the formation of tooth nerve supply.
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Affiliation(s)
- Päivi Kettunen
- Division of Anatomy and Cell Biology, Department of Biomedicine, University of Bergen, Jonas Lies vei 91, 5009 Bergen, Norway
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95
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Schwarz Q, Gu C, Fujisawa H, Sabelko K, Gertsenstein M, Nagy A, Taniguchi M, Kolodkin AL, Ginty DD, Shima DT, Ruhrberg C. Vascular endothelial growth factor controls neuronal migration and cooperates with Sema3A to pattern distinct compartments of the facial nerve. Genes Dev 2004; 18:2822-34. [PMID: 15545635 PMCID: PMC528901 DOI: 10.1101/gad.322904] [Citation(s) in RCA: 139] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Developing neurons accurately position their somata within the neural tube to make contact with appropriate neighbors and project axons to their preferred targets. Taking advantage of a collection of genetically engineered mouse mutants, we now demonstrate that the behavior of somata and axons of the facial nerve is regulated independently by two secreted ligands for the transmembrane receptor neuropilin 1 (Nrp1), the semaphorin Sema3A and the VEGF164 isoform of Vascular Endothelial Growth Factor. Although Sema3A is known to control the guidance of facial nerve axons, we now show that it is not required for the pathfinding of their somata. Vice versa, we find that VEGF164 is not required for axon guidance of facial motor neurons, but is essential for the correct migration of their somata. These observations demonstrate, for the first time, that VEGF contributes to neuronal patterning in vivo, and that different compartments of one cell can be co-ordinately patterned by structurally distinct ligands for a shared receptor.
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Affiliation(s)
- Quenten Schwarz
- Department of Cell Biology, Institute of Ophthalmology, University College London, London EC1V 9EL, United Kingdom
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96
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Michishita M, Ikeda T, Nakashiba T, Ogawa M, Tashiro K, Honjo T, Doi K, Itohara S, Endo S. Expression of Btcl2, a novel member of Btcl gene family, during development of the central nervous system. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 2004; 153:135-42. [PMID: 15464227 DOI: 10.1016/j.devbrainres.2004.06.012] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 06/14/2004] [Indexed: 10/26/2022]
Abstract
Cell-cell interactions are primarily mediated by secreted and transmembrane proteins which play essential roles in the neuronal circuit formation. However, molecular mechanisms underlying neuronal circuit formation, which is mediated by the cell-cell interactions, remain largely elusive. We isolated and characterized a novel gene, Btcl2 (brain-specific transmembrane protein containing CUB [complement subcomponent C1r/C1s, sea urchin protein Uegf, and BMP-1] and LDLa [low-density lipoprotein receptor domain class A] domains 2), using the signal sequence trap (SST) method. The extracellular domain of BTCL2 contains two CUB domains and an LDLa domain. BTCL2 and BTCL1 have similar domain structures, sharing 51% overall identity. The CUB1, CUB2, and LDLa domains of these two proteins share 63%, 72%, and 84% identity, respectively. The CUB domains of BTCL1 and BTCL2 share significant identity with those of neuropilins. Btcl2 mRNA was detected as a single 6-kb transcript in Northern blot analysis. In situ hybridization (ISH) analysis revealed that both Btcl1 and Btcl2 mRNAs were observed restrictively in brain throughout embryonic and postnatal stages. Btcl1 and Btcl2 mRNAs were expressed uniquely in the pontine nucleus and subplate, which are required for establishing the neuronal circuit formation. These results will aid in resolving the mechanisms underlying neuronal circuit formations (e.g., pontocerebellar and thalamocortical axon guidance) and permit more precise studies aimed at understanding the role of BTCL1 and BTCL2 in the central nervous system.
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Affiliation(s)
- Masaki Michishita
- Department of Veterinary Pathology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
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97
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Kutcher ME, Klagsbrun M, Mamluk R. VEGF is required for the maintenance of dorsal root ganglia blood vessels but not neurons during development. FASEB J 2004; 18:1952-4. [PMID: 15479766 DOI: 10.1096/fj.04-2320fje] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Vascular endothelial growth factor (VEGF) is a potent regulator of vascular function through its control of multiple endothelial cell functions. In addition to its key role in vascularization, VEGF has recently been shown to have neurotrophic activity during hypoxic stress. In the central and peripheral motor nervous system, VEGF treatment increased neuronal vascularization and perfusion, as well as having direct trophic effects on neurons and Schwann cells. However, the role of VEGF in the sensory nervous system remains unclear. To characterize the differential effects of VEGF on endothelial cells and neurons in sensory ganglia, we used explanted mouse dorsal root ganglia (DRG), a culture system containing neurons and endothelial cells in close apposition. We show that VEGF is expressed by neurons and satellite cells, but not by endothelial cells or pericytes. On the other hand, the tyrosine kinase VEGF receptor VEGFR-2 was robustly expressed by endothelial cells throughout the extensive DRG capillary network, but not found at either the transcript or protein level in sensory neurons or other nonendothelial cells of the DRG. Both soluble receptor sequestration of VEGF and small molecule kinase inhibition of VEGFR-2 signaling rapidly disrupted the connectivity, branching, and structural integrity of the capillary network of embryonic DRG; this effect was no longer evident postnatally. However, VEGF inhibition showed no detectable effect on neuronal health at any stage analyzed. These data suggest that endogenous VEGF is a strict requirement for vascular, but not neuronal, maintenance in developing sensory ganglia.
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Affiliation(s)
- Matthew E Kutcher
- Vascular Biology Program and Department of Surgery, Children's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA
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98
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Young HM, Anderson RB, Anderson CR. Guidance cues involved in the development of the peripheral autonomic nervous system. Auton Neurosci 2004; 112:1-14. [PMID: 15233925 DOI: 10.1016/j.autneu.2004.02.008] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2003] [Revised: 02/25/2004] [Accepted: 02/26/2004] [Indexed: 10/26/2022]
Abstract
All peripheral autonomic neurons arise from neural crest cells that migrate away from the neural tube and navigate to the location where ganglia will form. After differentiating into neurons, their axons then navigate to a variety of targets. During the development of the enteric nervous system, GDNF appears to play a role in inducing vagal neural crest cells to enter the gut, in retaining neural crest cells within the gut and in promoting the migration of neural crest cells along the gut. Sema3A regulates the entry of extrinsic axons into the distal hindgut, netrin-DCC signaling is responsible for the centripetal migration of cells to form the submucosal ganglia within the gut, Slit-Robo signaling prevents trunk level neural crest cells from entering the gut, and neurturin plays a role in the innervation of the circular muscle layer. During the development of the sympathetic nervous system, the migration of trunk neural crest cells through the somites is influenced by ephrin-Bs, Sema3A and F-spondin. The migration of neural crest cells ventrally beyond the somites requires neuregulin signaling and the clumping of cells into columns adjacent to the dorsal aorta is regulated by Sema3A. The rostral migration of cells to form the superior cervical ganglion (SCG) and the extension of axons along blood vessels involves artemin signaling through Ret and GFRalpha3, and the entry of sympathetic axons into target tissues involves neurotrophins and GDNF. Relatively little is known about the development of parasympathetic ganglia, but GDNF appears to play a role in the migration of some cranial ganglion precursors to their correct location, and both GDNF and neurturin are involved in the growth of parasympathetic axons into particular targets.
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Affiliation(s)
- H M Young
- Department of Anatomy and Cell Biology, University of Melbourne, 3010 VIC, Australia
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Basile JR, Barac A, Zhu T, Guan KL, Gutkind JS. Class IV semaphorins promote angiogenesis by stimulating Rho-initiated pathways through plexin-B. Cancer Res 2004; 64:5212-24. [PMID: 15289326 DOI: 10.1158/0008-5472.can-04-0126] [Citation(s) in RCA: 190] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The semaphorins are a large family of secreted and cell surface proteins that provide attractive and repulsive cues for axon guidance during neuronal development. Semaphorins share a conserved NH(2)-terminal Sema domain with their receptors, the plexins, which mediate neuronal cell adhesion, axon guidance, and maintenance of established neuronal pathways in the adult. Both semaphorins and plexins share structural homology with the extracellular domain of c-Met, a member of the scatter factor family of receptors. However, the highly conserved cytoplasmic region of plexins has no homology with the c-Met tyrosine kinase or with any other known protein. Using a recently developed antibody and RNA analysis, we found that high levels of plexin-B1 are expressed in endothelial cells. Whereas c-Met, with which plexin-B1 can interact, is known to be a potent promoter of angiogenesis, the effects of semaphorin-mediated plexin activation in endothelial cells are still poorly understood. Here, we examined the role of plexin-B1 activation in angiogenesis using a purified, secreted form of its ligand, Semaphorin 4D (Sema4D). Sema4D potently induced chemotaxis and tubulogenesis in endothelial cells and enhanced blood vessel formation in an in vivo mouse model. Interestingly, responses to Sema4D did not require c-Met activation. Instead, the use of chimeric plexin-B1 receptors, Rho inhibitors, and lentiviral gene delivery of interfering molecules revealed that these proangiogenic effects are dependent on a COOH-terminal PDZ-binding motif of plexin-B1, which binds two guanine nucleotide exchange factors for the small GTPase Rho, PDZ-RhoGEF and LARG, and are mediated by the activation of Rho-initiated pathways.
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Affiliation(s)
- John R Basile
- Oral and Pharyngeal Cancer Branch, National Institute of Dental and Craniofacial Research/NIH, 30 Convent Drive, Bethesda, MD 20892, USA
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Abstract
Successful implantation is the result of reciprocal interactions between the implantation-competent blastocyst and receptive uterus. Although various cellular aspects and molecular pathways of this dialogue have been identified, a comprehensive understanding of the implantation process is still missing. The receptive state of the uterus, which lasts for a limited period, is defined as the time when the uterine environment is conducive to blastocyst acceptance and implantation. A better understanding of the molecular signals that regulate uterine receptivity and implantation competency of the blastocyst is of clinical relevance because unraveling the nature of these signals may lead to strategies to correct implantation failure and improve pregnancy rates. Gene expression studies and genetically engineered mouse models have provided valuable clues to the implantation process with respect to specific growth factors, cytokines, lipid mediators, adhesion molecules, and transcription factors. However, a staggering amount of information from microarray experiments is also being generated at a rapid pace. If properly annotated and explored, this information will expand our knowledge regarding yet-to-be-identified unique, complementary, and/or redundant molecular pathways in implantation. It is hoped that the forthcoming information will generate new ideas and concepts for a process that is essential for maintaining procreation and solving major reproductive health issues in women.
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Affiliation(s)
- S K Dey
- Department of Pediatrics, Vanderbilt University Medical Center, MCN D4100, Nashville, Tennessee 37232, USA.
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