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Alotaibi FS, Alsadun MMR, Alsaiari SA, Ramakrishnan K, Yates EA, Fernig DG. Interactions of proteins with heparan sulfate. Essays Biochem 2024:EBC20230093. [PMID: 38646914 DOI: 10.1042/ebc20230093] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 03/22/2024] [Accepted: 04/02/2024] [Indexed: 04/23/2024]
Abstract
Heparan sulfate (HS) is a glycosaminoglycan, polysaccharides that are considered to have arisen in the last common unicellular ancestor of multicellular animals. In this light, the large interactome of HS and its myriad functions in relation to the regulation of cell communication are not surprising. The binding of proteins to HS determines their localisation and diffusion, essential for embryonic development and homeostasis. Following the biosynthesis of the initial heparosan polymer, the subsequent modifications comprise an established canonical pathway and a minor pathway. The more frequent former starts with N-deacetylation and N-sulfation of GlcNAc residues, the latter with C-5 epimerisation of a GlcA residue adjacent to a GlcNAc. The binding of proteins to HS is driven by ionic interactions. The multivalent effect arising from the many individual ionic bonds between a single protein and a polysaccharide chain results in a far stronger interaction than would be expected from an ion-exchange process. In many instances, upon binding, both parties undergo substantial conformational change, the resulting hydrogen and van der Waal bonds contributing significant free energy to the binding reaction. Nevertheless, ionic bonds dominate the protein-polysaccharide interaction kinetically. Together with the multivalent effect, this provides an explanation for the observed trapping of HS-binding proteins in extracellular matrix. Importantly, individual ionic bonds have been observed to be dynamic; breaking and reforming, while the protein remains bound to the polysaccharide. These considerations lead to a model for 1D diffusion of proteins in extracellular matrix on HS, involving mechanisms such as sliding, chain switching and rolling.
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Affiliation(s)
- Faizah S Alotaibi
- Department of Biochemistry, Systems and Cell Biology, Institute of Molecular, Integrative and Systems Biology, University of Liverpool, Liverpool L69 7ZB, U.K
| | - Marim M R Alsadun
- Department of Biochemistry, Systems and Cell Biology, Institute of Molecular, Integrative and Systems Biology, University of Liverpool, Liverpool L69 7ZB, U.K
- Department of Biology, University of Tabuk, Tabuk 71491, Saudi Arabia
| | - Sarah A Alsaiari
- Department of Biochemistry, Systems and Cell Biology, Institute of Molecular, Integrative and Systems Biology, University of Liverpool, Liverpool L69 7ZB, U.K
- Department of Biological Sciences, College of Science, University of Jeddah, Jeddah 21589, Saudi Arabia
| | - Krithika Ramakrishnan
- Department of Biochemistry, Systems and Cell Biology, Institute of Molecular, Integrative and Systems Biology, University of Liverpool, Liverpool L69 7ZB, U.K
| | - Edwin A Yates
- Department of Biochemistry, Systems and Cell Biology, Institute of Molecular, Integrative and Systems Biology, University of Liverpool, Liverpool L69 7ZB, U.K
| | - David G Fernig
- Department of Biochemistry, Systems and Cell Biology, Institute of Molecular, Integrative and Systems Biology, University of Liverpool, Liverpool L69 7ZB, U.K
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HS, an Ancient Molecular Recognition and Information Storage Glycosaminoglycan, Equips HS-Proteoglycans with Diverse Matrix and Cell-Interactive Properties Operative in Tissue Development and Tissue Function in Health and Disease. Int J Mol Sci 2023; 24:ijms24021148. [PMID: 36674659 PMCID: PMC9867265 DOI: 10.3390/ijms24021148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 12/23/2022] [Accepted: 12/27/2022] [Indexed: 01/11/2023] Open
Abstract
Heparan sulfate is a ubiquitous, variably sulfated interactive glycosaminoglycan that consists of repeating disaccharides of glucuronic acid and glucosamine that are subject to a number of modifications (acetylation, de-acetylation, epimerization, sulfation). Variable heparan sulfate chain lengths and sequences within the heparan sulfate chains provide structural diversity generating interactive oligosaccharide binding motifs with a diverse range of extracellular ligands and cellular receptors providing instructional cues over cellular behaviour and tissue homeostasis through the regulation of essential physiological processes in development, health, and disease. heparan sulfate and heparan sulfate-PGs are integral components of the specialized glycocalyx surrounding cells. Heparan sulfate is the most heterogeneous glycosaminoglycan, in terms of its sequence and biosynthetic modifications making it a difficult molecule to fully characterize, multiple ligands also make an elucidation of heparan sulfate functional properties complicated. Spatio-temporal presentation of heparan sulfate sulfate groups is an important functional determinant in tissue development and in cellular control of wound healing and extracellular remodelling in pathological tissues. The regulatory properties of heparan sulfate are mediated via interactions with chemokines, chemokine receptors, growth factors and morphogens in cell proliferation, differentiation, development, tissue remodelling, wound healing, immune regulation, inflammation, and tumour development. A greater understanding of these HS interactive processes will improve therapeutic procedures and prognoses. Advances in glycosaminoglycan synthesis and sequencing, computational analytical carbohydrate algorithms and advanced software for the evaluation of molecular docking of heparan sulfate with its molecular partners are now available. These advanced analytic techniques and artificial intelligence offer predictive capability in the elucidation of heparan sulfate conformational effects on heparan sulfate-ligand interactions significantly aiding heparan sulfate therapeutics development.
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Cui H, Cheng X, Batool T, Zhang X, Li JP. Glucuronyl C5-epimerase is crucial for epithelial cell maturation during embryonic lung development. Glycobiology 2020; 31:223-230. [PMID: 32651954 DOI: 10.1093/glycob/cwaa065] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 06/28/2020] [Accepted: 07/06/2020] [Indexed: 12/23/2022] Open
Abstract
Glucuronyl C5-epimerase (Hsepi) is a key enzyme in the biosynthesis of heparan sulfate that is a sulfated polysaccharide expressed on the cell surface and in the extracellular matrix of alveolar walls and blood vessels. Targeted interruption of the Hsepi gene, Glce, in mice resulted in neonatal lethality, which is most likely due to lung atelectasis. In this study, we examined the potential mechanisms behind the defect in lung development. Histological analysis of the lungs from embryos revealed no difference in the morphology between wild-type and mutant animals up to E16.5. This suggests that the initial events leading to formation of the lung primordium and branching morphogenesis are not disturbed. However, the distal lung of E17.5-18.5 mutants is still populated by epithelial tubules, lacking the typical saccular structural characteristic of a normal E17.5 lung. Immunostaining revealed strong signals of surfactant protein-C, but a weaker signal of T1α in the mutant lungs in comparison to WT littermates, suggesting differentiation of type I alveolar epithelial cells (AT1) is impaired. One of the parameters contributed to the failure of AT1 maturation is reduced vascularization in the developing lungs.
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Affiliation(s)
- Hao Cui
- College of Life Science, Jiangxi Normal University, 99 Ziyang Avenue, 330022, Nanchang, China.,Department of Medical Biochemistry and Microbiology, SciLifeLab Uppsala, The Biomedical Center, University of Uppsala, Box 582, Husargatan 3, S-75123, Uppsala, Sweden
| | - Xiaowen Cheng
- Department of Medical Biochemistry and Microbiology, SciLifeLab Uppsala, The Biomedical Center, University of Uppsala, Box 582, Husargatan 3, S-75123, Uppsala, Sweden
| | - Tahira Batool
- Department of Medical Biochemistry and Microbiology, SciLifeLab Uppsala, The Biomedical Center, University of Uppsala, Box 582, Husargatan 3, S-75123, Uppsala, Sweden
| | - Xiao Zhang
- Department of Neuroscience and Pharmacology, University of Uppsala, Box 582, Husargatan 3, S-75123, Uppsala, Sweden
| | - Jin-Ping Li
- Department of Medical Biochemistry and Microbiology, SciLifeLab Uppsala, The Biomedical Center, University of Uppsala, Box 582, Husargatan 3, S-75123, Uppsala, Sweden
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Assessment of the nitrofen model of congenital diaphragmatic hernia and of the dysregulated factors involved in pulmonary hypoplasia. Pediatr Surg Int 2019; 35:41-61. [PMID: 30386897 DOI: 10.1007/s00383-018-4375-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/18/2018] [Indexed: 02/08/2023]
Abstract
PURPOSE To study pulmonary hypoplasia (PH) associated with congenital diaphragmatic hernia (CDH), investigators have been employing a fetal rat model based on nitrofen administration to dams. Herein, we aimed to: (1) investigate the validity of the model, and (2) synthesize the main biological pathways implicated in the development of PH associated with CDH. METHODS Using a defined strategy, we conducted a systematic review of the literature searching for studies reporting the incidence of CDH or factors involved in PH development. We also searched for PH factor interactions, relevance to lung development and to human PH. RESULTS Of 335 full-text articles, 116 reported the incidence of CDH after nitrofen exposure or dysregulated factors in the lungs of nitrofen-exposed rat fetuses. CDH incidence: 54% (27-85%) fetuses developed a diaphragmatic defect, whereas the whole litter had PH in varying degrees. Downregulated signaling pathways included FGF/FGFR, BMP/BMPR, Sonic Hedgehog and retinoid acid signaling pathway, resulting in a delay in early epithelial differentiation, immature distal epithelium and dysfunctional mesenchyme. CONCLUSIONS The nitrofen model effectively reproduces PH as it disrupts pathways that are critical for lung branching morphogenesis and alveolar differentiation. The low CDH rate confirms that PH is an associated phenomenon rather than the result of mechanical compression alone.
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Sun C, Marcello M, Li Y, Mason D, Lévy R, Fernig DG. Selectivity in glycosaminoglycan binding dictates the distribution and diffusion of fibroblast growth factors in the pericellular matrix. Open Biol 2016; 6:150277. [PMID: 27009190 PMCID: PMC4821244 DOI: 10.1098/rsob.150277] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Accepted: 03/02/2016] [Indexed: 12/13/2022] Open
Abstract
The range of biological outcomes generated by many signalling proteins in development and homeostasis is increased by their interactions with glycosaminoglycans, particularly heparan sulfate (HS). This interaction controls the localization and movement of these signalling proteins, but whether such control depends on the specificity of the interactions is not known. We used five fibroblast growth factors with an N-terminal HaloTag (Halo-FGFs) for fluorescent labelling, with well-characterized and distinct HS-binding properties, and measured their binding and diffusion in pericellular matrix of fixed rat mammary 27 fibroblasts. Halo-FGF1, Halo-FGF2 and Halo-FGF6 bound to HS, whereas Halo-FGF10 also interacted with chondroitin sulfate/dermatan sulfate, and FGF20 did not bind detectably. The distribution of bound FGFs in the pericellular matrix was not homogeneous, and for FGF10 exhibited striking clusters. Fluorescence recovery after photobleaching showed that FGF2 and FGF6 diffused faster, whereas FGF1 diffused more slowly, and FGF10 was immobile. The results demonstrate that the specificity of the interactions of proteins with glycosaminoglycans controls their binding and diffusion. Moreover, cells regulate the spatial distribution of different protein-binding sites in glycosaminoglycans independently of each other, implying that the extracellular matrix has long-range structure.
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Affiliation(s)
- Changye Sun
- Department of Biochemistry, Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Marco Marcello
- Centre for Cell Imaging, Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Yong Li
- Department of Biochemistry, Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - David Mason
- Centre for Cell Imaging, Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - Raphaël Lévy
- Department of Biochemistry, Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - David G Fernig
- Department of Biochemistry, Institute of Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
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Mižíková I, Morty RE. The Extracellular Matrix in Bronchopulmonary Dysplasia: Target and Source. Front Med (Lausanne) 2015; 2:91. [PMID: 26779482 PMCID: PMC4688343 DOI: 10.3389/fmed.2015.00091] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 12/08/2015] [Indexed: 12/22/2022] Open
Abstract
Bronchopulmonary dysplasia (BPD) is a common complication of preterm birth that contributes significantly to morbidity and mortality in neonatal intensive care units. BPD results from life-saving interventions, such as mechanical ventilation and oxygen supplementation used to manage preterm infants with acute respiratory failure, which may be complicated by pulmonary infection. The pathogenic pathways driving BPD are not well-delineated but include disturbances to the coordinated action of gene expression, cell-cell communication, physical forces, and cell interactions with the extracellular matrix (ECM), which together guide normal lung development. Efforts to further delineate these pathways have been assisted by the use of animal models of BPD, which rely on infection, injurious mechanical ventilation, or oxygen supplementation, where histopathological features of BPD can be mimicked. Notable among these are perturbations to ECM structures, namely, the organization of the elastin and collagen networks in the developing lung. Dysregulated collagen deposition and disturbed elastin fiber organization are pathological hallmarks of clinical and experimental BPD. Strides have been made in understanding the disturbances to ECM production in the developing lung, but much still remains to be discovered about how ECM maturation and turnover are dysregulated in aberrantly developing lungs. This review aims to inform the reader about the state-of-the-art concerning the ECM in BPD, to highlight the gaps in our knowledge and current controversies, and to suggest directions for future work in this exciting and complex area of lung development (patho)biology.
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Affiliation(s)
- Ivana Mižíková
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany; Pulmonology, Department of Internal Medicine, University of Giessen and Marburg Lung Center, Giessen, Germany
| | - Rory E Morty
- Department of Lung Development and Remodelling, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany; Pulmonology, Department of Internal Medicine, University of Giessen and Marburg Lung Center, Giessen, Germany
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Abstract
Heparan sulfate (HS) glycosaminoglycan chains contain highly modified HS domains that are separated by sections of sparse or no modification. HS domains are central to the role of HS in protein binding and mediating protein-protein interactions in the extracellular matrix. Since HS domains are not genetically encoded, they are impossible to visualize and study with conventional methods in vivo. Here we describe a transgenic approach using previously described single chain variable fragment (scFv) antibodies that bind HS in vitro and on tissue sections with different specificities. By engineering a secretion signal and a fluorescent protein to the scFvs and transgenically expressing these fluorescently tagged antibodies in Caenorhabditis elegans, we are able to directly visualize specific HS domains in live animals (Attreed et al. Nat Methods 9(5):477-479, 2012). The approach allows concomitant colabeling of multiple epitopes, the study of HS dynamics and, could lend itself to a genetic analysis of HS domain biosynthesis or to visualize other nongenetically encoded or posttranslational modifications.
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Xu R, Ori A, Rudd TR, Uniewicz KA, Ahmed YA, Guimond SE, Skidmore MA, Siligardi G, Yates EA, Fernig DG. Diversification of the structural determinants of fibroblast growth factor-heparin interactions: implications for binding specificity. J Biol Chem 2012; 287:40061-73. [PMID: 23019343 DOI: 10.1074/jbc.m112.398826] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The functions of a large number (>435) of extracellular regulatory proteins are controlled by their interactions with heparan sulfate (HS). In the case of fibroblast growth factors (FGFs), HS binding determines their transport between cells and is required for the assembly of high affinity signaling complexes with their cognate FGF receptor. However, the specificity of the interaction of FGFs with HS is still debated. Here, we use a panel of FGFs (FGF-1, FGF-2, FGF-7, FGF-9, FGF-18, and FGF-21) spanning five FGF subfamilies to probe their specificities for HS at different levels as follows: binding parameters, identification of heparin-binding sites (HBSs) in the FGFs, changes in their secondary structure caused by heparin binding and structures in the sugar required for binding. For interaction with heparin, the FGFs exhibit K(D) values varying between 38 nM (FGF-18) and 620 nM (FGF-9) and association rate constants spanning over 20-fold (FGF-1, 2,900,000 M(-1) s(-1) and FGF-9, 130,000 M(-1) s(-1)). The canonical HBS in FGF-1, FGF-2, FGF-7, FGF-9, and FGF-18 differs in its size, and these FGFs have a different complement of secondary HBS, ranging from none (FGF-9) to two (FGF-1). Differential scanning fluorimetry identified clear preferences in these FGFs for distinct structural features in the polysaccharide. These data suggest that the differences in heparin-binding sites in both the protein and the sugar are greatest between subfamilies and may be more restricted within a FGF subfamily in accord with the known conservation of function within FGF subfamilies.
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Affiliation(s)
- Ruoyan Xu
- Institute of Integrative Biology, Department of Chemical and Structural Biology, University of Liverpool, Crown Street, Liverpool L69 7ZB, United Kingdom
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Duchesne L, Octeau V, Bearon RN, Beckett A, Prior IA, Lounis B, Fernig DG. Transport of fibroblast growth factor 2 in the pericellular matrix is controlled by the spatial distribution of its binding sites in heparan sulfate. PLoS Biol 2012; 10:e1001361. [PMID: 22815649 PMCID: PMC3398970 DOI: 10.1371/journal.pbio.1001361] [Citation(s) in RCA: 92] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2011] [Accepted: 06/06/2012] [Indexed: 12/31/2022] Open
Abstract
The heparan sulfate (HS) chains of proteoglycans are a key regulatory component of the extracellular matrices of animal cells, including the pericellular matrix around the plasma membrane. In these matrices they regulate transport, gradient formation, and effector functions of over 400 proteins central to cell communication. HS from different matrices differs in its selectivity for its protein partners. However, there has been no direct test of how HS in the matrix regulates the transport of its partner proteins. We address this issue by single molecule imaging and tracking in fibroblast pericellular matrix of fibroblast growth factor 2 (FGF2), stoichiometrically labelled with small gold nanoparticles. Transmission electron microscopy and photothermal heterodyne imaging (PHI) show that the spatial distribution of the HS-binding sites for FGF2 in the pericellular matrix is heterogeneous over length scales ranging from 22 nm to several µm. Tracking of individual FGF2 by PHI in the pericellular matrix of living cells demonstrates that they undergo five distinct types of motion. They spend much of their time in confined motion (∼110 nm diameter), but they are not trapped and can escape by simple diffusion, which may be slow, fast, or directed. These substantial translocations (µm) cover distances far greater than the length of a single HS chain. Similar molecular motion persists in fixed cells, where the movement of membrane PGs is impeded. We conclude that FGF2 moves within the pericellular matrix by translocating from one HS-binding site to another. The binding sites on HS chains form non-random, heterogeneous networks. These promote FGF2 confinement or substantial translocation depending on their spatial organisation. We propose that this spatial organisation, coupled to the relative selectivity and the availability of HS-binding sites, determines the transport of FGF2 in matrices. Similar mechanisms are likely to underpin the movement of many other HS-binding effectors.
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Affiliation(s)
- Laurence Duchesne
- Department of Structural and Chemical Biology, Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
- Institut du Fer à Moulin, UMR-S 839 INSERM, University Pierre and Marie Curie, Paris, France
- UMR 6290 CNRS, Institut de Génétique et Développement de Rennes, Université de Rennes 1, Campus de Beaulieu, Rennes, France
- * E-mail: (LD); (DGF)
| | - Vivien Octeau
- Laboratoire Photonique Numérique et Nanosciences, Université de Bordeaux, UMR 5298 CNRS and Institut d'Optique Graduate School, Talence, France
| | - Rachel N. Bearon
- Department of Mathematical Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Alison Beckett
- Physiological Laboratory, University of Liverpool, Liverpool, United Kingdom
| | - Ian A. Prior
- Physiological Laboratory, University of Liverpool, Liverpool, United Kingdom
| | - Brahim Lounis
- Laboratoire Photonique Numérique et Nanosciences, Université de Bordeaux, UMR 5298 CNRS and Institut d'Optique Graduate School, Talence, France
| | - David G. Fernig
- Department of Structural and Chemical Biology, Institute of Integrative Biology, University of Liverpool, Liverpool, United Kingdom
- * E-mail: (LD); (DGF)
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Corbett HJ, Connell MG, Fernig DG, Losty PD, Jesudason EC. ANG-1 TIE-2 and BMPR signalling defects are not seen in the nitrofen model of pulmonary hypertension and congenital diaphragmatic hernia. PLoS One 2012; 7:e35364. [PMID: 22539968 PMCID: PMC3335125 DOI: 10.1371/journal.pone.0035364] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2012] [Accepted: 03/14/2012] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND Pulmonary hypertension (PH) is a lethal disease that is associated with characteristic histological abnormalities of the lung vasculature and defects of angiopoetin-1 (ANG-1), TIE-2 and bone morphogenetic protein receptor (BMPR)-related signalling. We hypothesized that if these signalling defects cause PH generically, they will be readily identifiable perinatally in congenital diaphragmatic hernia (CDH), where the typical pulmonary vascular changes are present before birth and are accompanied by PH after birth. METHODS CDH (predominantly left-sided, LCDH) was created in Sprague-Dawley rat pups by e9.5 maternal nitrofen administration. Left lungs from normal and LCDH pups were compared at fetal and postnatal time points for ANG-1, TIE-2, phosphorylated-TIE-2, phosphorylated-SMAD1/5/8 and phosphorylated-ERK1/2 by immunoprecipitation and Western blotting of lung protein extracts and by immunohistochemistry on lung sections. RESULTS In normal lung, pulmonary ANG-1 protein levels fall between fetal and postnatal life, while TIE-2 levels increase. Over the corresponding time period, LCDH lung retained normal expression of ANG-1, TIE-2, phosphorylated-TIE-2 and, downstream of BMPR, phosphorylated-SMAD1/5/8 and phosphorylated-p44/42. CONCLUSION In PH and CDH defects of ANG-1/TIE-2/BMPR-related signalling are not essential for the lethal vasculopathy.
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Affiliation(s)
- Harriet Jane Corbett
- Division of Child Health, Institute of Translational Medicine, The University of Liverpool, Liverpool, United Kingdom.
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