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Wagenseil JE, Mecham RP. Vascular extracellular matrix and arterial mechanics. Physiol Rev 2009; 89:957-89. [PMID: 19584318 DOI: 10.1152/physrev.00041.2008] [Citation(s) in RCA: 656] [Impact Index Per Article: 43.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
An important factor in the transition from an open to a closed circulatory system was a change in vessel wall structure and composition that enabled the large arteries to store and release energy during the cardiac cycle. The component of the arterial wall in vertebrates that accounts for these properties is the elastic fiber network organized by medial smooth muscle. Beginning with the onset of pulsatile blood flow in the developing aorta, smooth muscle cells in the vessel wall produce a complex extracellular matrix (ECM) that will ultimately define the mechanical properties that are critical for proper function of the adult vascular system. This review discusses the structural ECM proteins in the vertebrate aortic wall and will explore how the choice of ECM components has changed through evolution as the cardiovascular system became more advanced and pulse pressure increased. By correlating vessel mechanics with physiological blood pressure across animal species and in mice with altered vessel compliance, we show that cardiac and vascular development are physiologically coupled, and we provide evidence for a universal elastic modulus that controls the parameters of ECM deposition in vessel wall development. We also discuss mechanical models that can be used to design better tissue-engineered vessels and to test the efficacy of clinical treatments.
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Affiliation(s)
- Jessica E Wagenseil
- Department of Biomedical Engineering, Saint Louis University, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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52
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Chen Y, Lei YP, Zheng HX, Wang W, Cheng HB, Zhang J, Wang HY, Jin L, Li H. A Novel Mutation (C1425Y) in the FBN2 Gene in a Father and Son with Congenital Contractural Arachnodactyly. Genet Test Mol Biomarkers 2009; 13:295-300. [PMID: 19473076 DOI: 10.1089/gtmb.2008.0132] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Ying Chen
- Center for Reproduction and Genetics, Nanjing Medical University Affiliated Suzhou Hospital, Suzhou, P.R. China
| | - Yun-Ping Lei
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences and Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Hong-Xiang Zheng
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences and Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Wei Wang
- Center for Reproduction and Genetics, Nanjing Medical University Affiliated Suzhou Hospital, Suzhou, P.R. China
| | - Hong-Bo Cheng
- Center for Reproduction and Genetics, Nanjing Medical University Affiliated Suzhou Hospital, Suzhou, P.R. China
| | - Jing Zhang
- Center for Reproduction and Genetics, Nanjing Medical University Affiliated Suzhou Hospital, Suzhou, P.R. China
| | - Hong-Yan Wang
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences and Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Li Jin
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, School of Life Sciences and Institutes of Biomedical Sciences, Fudan University, Shanghai, China
| | - Hong Li
- Center for Reproduction and Genetics, Nanjing Medical University Affiliated Suzhou Hospital, Suzhou, P.R. China
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Callewaert BL, Loeys BL, Ficcadenti A, Vermeer S, Landgren M, Kroes HY, Yaron Y, Pope M, Foulds N, Boute O, Galán F, Kingston H, Van der Aa N, Salcedo I, Swinkels ME, Wallgren-Pettersson C, Gabrielli O, De Backer J, Coucke PJ, De Paepe AM. Comprehensive clinical and molecular assessment of 32 probands with congenital contractural arachnodactyly: report of 14 novel mutations and review of the literature. Hum Mutat 2009; 30:334-41. [PMID: 19006240 DOI: 10.1002/humu.20854] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Beals-Hecht syndrome or congenital contractural arachnodactyly (CCA) is a rare, autosomal dominant connective tissue disorder characterized by crumpled ears, arachnodactyly, contractures, and scoliosis. Recent reports also mention aortic root dilatation, a finding previously thought to differentiate the condition from Marfan syndrome (MFS). In many cases, the condition is caused by mutations in the fibrillin 2 gene (FBN2) with 26 mutations reported so far, all located in the middle region of the gene (exons 23-34). We directly sequenced the entire FBN2 gene in 32 probands clinically diagnosed with CCA. In 14 probands, we found 13 new and one previously described FBN2 mutation including a mutation in exon 17, expanding the region in which FBN2 mutations occur in CCA. Review of the literature showed that the phenotype of the FBN2 positive patients was comparable to all previously published FBN2-positive patients. In our FBN2-positive patients, cardiovascular involvement included mitral valve prolapse in two adult patients and aortic root enlargement in three patients. Whereas the dilatation regressed in one proband, it remained marked in a child proband (z-score: 4.09) and his father (z-score: 2.94), warranting echocardiographic follow-up. We confirm paradoxical patellar laxity and report keratoconus, shoulder muscle hypoplasia, and pyeloureteral junction stenosis as new features. In addition, we illustrate large intrafamilial variability. Finally, the FBN2-negative patients in this cohort were clinically indistinguishable from all published FBN2-positive patients harboring a FBN2 mutation, suggesting locus heterogeneity.
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Frédéric MY, Monino C, Marschall C, Hamroun D, Faivre L, Jondeau G, Klein HG, Neumann L, Gautier E, Binquet C, Maslen C, Godfrey M, Gupta P, Milewicz D, Boileau C, Claustres M, Béroud C, Collod-Béroud G. The FBN2 gene: new mutations, locus-specific database (Universal Mutation Database FBN2), and genotype-phenotype correlations. Hum Mutat 2009; 30:181-90. [PMID: 18767143 DOI: 10.1002/humu.20794] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Congenital contractural arachnodactyly (CCA) is an extremely rare disease, due to mutations in the FBN2 gene encoding fibrillin-2. Another member of the fibrillin family, the FBN1 gene, is involved in a broad phenotypic continuum of connective-tissue disorders including Marfan syndrome. Identifying not only what is in common but also what differentiates these two proteins should enable us to better comprehend their respective functions and better understand the multitude of diseases in which these two genes are involved. In 1995 we created a locus-specific database (LSDB) for FBN1 mutations with the Universal Mutation Database (UMD) tool. To facilitate comparison of identified mutations in these two genes and search for specific functional areas, we created an LSDB for the FBN2 gene: the UMD-FBN2 database. This database lists 26 published and six newly identified mutations that mainly comprise missense and splice-site mutations. Although the number of described FBN2 mutations was low, the frequency of joint dislocation was significantly higher with missense mutations when compared to splice site mutations.
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55
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Desmet FO, Hamroun D, Lalande M, Collod-Béroud G, Claustres M, Béroud C. Human Splicing Finder: an online bioinformatics tool to predict splicing signals. Nucleic Acids Res 2009; 37:e67. [PMID: 19339519 PMCID: PMC2685110 DOI: 10.1093/nar/gkp215] [Citation(s) in RCA: 1992] [Impact Index Per Article: 132.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Thousands of mutations are identified yearly. Although many directly affect protein expression, an increasing proportion of mutations is now believed to influence mRNA splicing. They mostly affect existing splice sites, but synonymous, non-synonymous or nonsense mutations can also create or disrupt splice sites or auxiliary cis-splicing sequences. To facilitate the analysis of the different mutations, we designed Human Splicing Finder (HSF), a tool to predict the effects of mutations on splicing signals or to identify splicing motifs in any human sequence. It contains all available matrices for auxiliary sequence prediction as well as new ones for binding sites of the 9G8 and Tra2-β Serine-Arginine proteins and the hnRNP A1 ribonucleoprotein. We also developed new Position Weight Matrices to assess the strength of 5′ and 3′ splice sites and branch points. We evaluated HSF efficiency using a set of 83 intronic and 35 exonic mutations known to result in splicing defects. We showed that the mutation effect was correctly predicted in almost all cases. HSF could thus represent a valuable resource for research, diagnostic and therapeutic (e.g. therapeutic exon skipping) purposes as well as for global studies, such as the GEN2PHEN European Project or the Human Variome Project.
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56
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Gansner JM, Madsen EC, Mecham RP, Gitlin JD. Essential role for fibrillin-2 in zebrafish notochord and vascular morphogenesis. Dev Dyn 2008; 237:2844-61. [PMID: 18816837 DOI: 10.1002/dvdy.21705] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Recent studies demonstrate that lysyl oxidase cuproenzymes are critical for zebrafish notochord formation, but the molecular mechanisms of copper-dependent notochord morphogenesis are incompletely understood. We, therefore, conducted a forward genetic screen for zebrafish mutants that exhibit notochord sensitivity to lysyl oxidase inhibition, yielding a mutant with defects in notochord and vascular morphogenesis, puff daddygw1 (pfdgw1). Meiotic mapping and cloning reveal that the pfdgw1 phenotype results from disruption of the gene encoding the extracellular matrix protein fibrillin-2, and the spatiotemporal expression of fibrillin-2 is consistent with the pfdgw1 phenotype. Furthermore, each aspect of the pfdgw1 phenotype is recapitulated by morpholino knockdown of fibrillin-2. Taken together, the data reveal a genetic interaction between fibrillin-2 and the lysyl oxidases in notochord formation and demonstrate the importance of fibrillin-2 in specific early developmental processes in zebrafish.
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Affiliation(s)
- John M Gansner
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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57
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Nishimura A, Sakai H, Ikegawa S, Kitoh H, Haga N, Ishikiriyama S, Nagai T, Takada F, Ohata T, Tanaka F, Kamasaki H, Saitsu H, Mizuguchi T, Matsumoto N. FBN2, FBN1, TGFBR1, and TGFBR2 analyses in congenital contractural arachnodactyly. Am J Med Genet A 2007; 143A:694-8. [PMID: 17345643 DOI: 10.1002/ajmg.a.31639] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
FBN2, FBN1, TGFBR1, and TGFBR2 were analyzed by direct sequencing in 15 probands with suspected congenital contractural arachnodactyly (CCA). A total of four novel FBN2 mutations were found in four probands (27%, 4/15), but remaining the 11 did not show any abnormality in either of the genes. This study indicated that FBN2 mutations were major abnormality in CCA, and TGFBR and FBN1 defects may not be responsible for the disorder. FBN2 mutations were only found at introns 30, 31, and 35 in this study. Thus analysis of a mutational hotspot from exons 22 to 36 (a middle part) of FBN2 should be prioritized in CCA as previously suggested.
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Affiliation(s)
- Akira Nishimura
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Japan
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58
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Guo G, Bauer S, Hecht J, Schulz MH, Busche A, Robinson PN. A short ultraconserved sequence drives transcription from an alternate FBN1 promoter. Int J Biochem Cell Biol 2007; 40:638-50. [PMID: 17996480 DOI: 10.1016/j.biocel.2007.09.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2007] [Revised: 09/25/2007] [Accepted: 09/25/2007] [Indexed: 11/16/2022]
Abstract
FBN1, the gene mutated in Marfan syndrome, encodes fibrillin-1, a large glycoprotein component of the extracellular microfibrils. Human FBN1 has three untranslated upstream exons, and homologous sequences can be identified in a number of mammalian species. In this work, we have used functional assays to characterize the FBN1 upstream region. Sequences upstream of exon 1 and at least two of the upstream untranslated exons were shown to possess promoter activity in vitro. The strongest activity in luciferase assays was shown for sequences upstream of the untranslated exon A. Sequence analysis of the sequences in and upstream of exon A in humans and six other mammalian species demonstrated several highly conserved potential cis-acting sequences as well as a 66-basepair (bp) ultraconserved sequence with nearly perfect conservation in the seven species. The ultraconserved sequence contains an initiator element (Inr), a downstream promoter element (DPE), and a 10-bp palindromic element. Mutational assays showed that both the Inr and the DPE are critical for full promoter activity. A mutation of the 10-bp palindromic element completely abolished basal promoter activity. The element was shown to bind specifically to an unknown nuclear protein by electrophoretic mobility shift assay. Ultraconservation within an alternate promoter has not been previously reported. We suggest that the ultraconservation may reflect the importance of finely tuned regulation of alternate transcription of FBN1 and that the sequences involved have been under negative selective pressure for at least the last 180 million years of mammalian evolution.
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Affiliation(s)
- Gao Guo
- Institute for Medical Genetics, Charité Universitätsmedizin Berlin, Augustenburger Platz 1, 13353 Berlin, Germany
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59
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Yu J, Tirlapur U, Fairbank J, Handford P, Roberts S, Winlove CP, Cui Z, Urban J. Microfibrils, elastin fibres and collagen fibres in the human intervertebral disc and bovine tail disc. J Anat 2007; 210:460-71. [PMID: 17428205 PMCID: PMC2100288 DOI: 10.1111/j.1469-7580.2007.00707.x] [Citation(s) in RCA: 134] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The distribution of microfibrils was studied immunohistochemically in intervertebral discs taken from young normal human surgical cases and from the bovine tail. Co-localization of microfibrils and elastin fibres was examined by dual immunostaining of fibrillin-1 and elastin. Collagen fibre network orientation was studied by using polarized filters. A similar microfibrillar network was seen in both bovine and human discs with network organization being completely different from region to region. In the outer annulus fibrosus (OAF), abundant microfibrils organized in bundles were mainly distributed in the interterritorial matrix. In addition, the microfibril bundles were orientated parallel to each other and co-localized highly with elastin fibres. Within each lamella, co-localized microfibrils and elastin fibres were aligned in the same direction as the collagen fibres. In the interlamellar space, a dense co-localized network, staining for both microfibrils and elastin fibres, was apparent; immunostaining for both molecules was noticeably stronger than within lamellae. In the inner annulus fibrosus, the microfibrils were predominantly visible as a filamentous mesh network, both in the interterritorial matrix and also around the cells. The microfibrils in this region co-localized with elastin fibres far less than in the OAF. In nucleus pulposus, filamentous microfibrils were organized mainly around the cells where elastin fibres were hardly detected. By contrast, sparse elastin fibres, with a few of microfibrils, were visible in the interterritorial matrix. The results of this study suggest the microfibrillar network of the annulus may play a mechanical role while that around the cells of the nucleus may be more involved in regulating cell function.
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Affiliation(s)
- Jing Yu
- Department of Physiology, Anatomy and Genetics, University of Oxford, UK.
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Abstract
PURPOSE OF REVIEW Pelvic organ prolapse is a common disease that negatively affects the lives of women. To date, basic science research into the pathogenesis of prolapse has been limited. The vagina and its supportive connective tissues provide one of the primary mechanisms of support to the pelvic organs. This review summarizes our current understanding of the alterations in these tissues in women with prolapse. RECENT FINDINGS Current research suggests that the vagina and its supportive tissues actively remodel in response to different environmental stimuli. The literature has many shortcomings due to restricted access to tissue, absence of longitudinal data, and limited animal models. Nevertheless, recent studies indicate that within prolapsed tissue metabolism of collagen and elastin is altered. Thus, not only the synthesis of those structural proteins but also the balance between the activity of the major proteolytic enzymes that degrade them and the inhibitors of proteolysis are important components to consider in studies on the pathogenesis of pelvic organ prolapse. SUMMARY Biochemical studies of the vagina and its supportive connective tissues have improved understanding of the contribution of altered connective tissue to the pathogenesis of prolapse. It is important to continue research in this area, as the knowledge gained from these studies will allow for the development of innovative reconstructive procedures and the establishment of preventive measures.
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Affiliation(s)
- Marianna Alperin
- Department of Obstetrics, Gynecology and Reproductive Sciences, Division of Gynecological Specialties, Magee-Women's Hospital and Magee Research Institute, University of Pittsburgh, Pittsburgh, PA 15213, USA
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Sakai H, Visser R, Ikegawa S, Ito E, Numabe H, Watanabe Y, Mikami H, Kondoh T, Kitoh H, Sugiyama R, Okamoto N, Ogata T, Fodde R, Mizuno S, Takamura K, Egashira M, Sasaki N, Watanabe S, Nishimaki S, Takada F, Nagai T, Okada Y, Aoka Y, Yasuda K, Iwasa M, Kogaki S, Harada N, Mizuguchi T, Matsumoto N. Comprehensive genetic analysis of relevant four genes in 49 patients with Marfan syndrome or Marfan-related phenotypes. Am J Med Genet A 2006; 140:1719-25. [PMID: 16835936 DOI: 10.1002/ajmg.a.31353] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In order to evaluate the contribution of FBN1, FBN2, TGFBR1, and TGFBR2 mutations to the Marfan syndrome (MFS) phenotype, the four genes were analyzed by direct sequencing in 49 patients with MFS or suspected MFS as a cohort study. A total of 27 FBN1 mutations (22 novel) in 27 patients (55%, 27/49), 1 novel TGFBR1 mutation in 1 (2%, 1/49), and 2 recurrent TGFBR2 mutations in 2 (4%, 2/49) were identified. No FBN2 mutation was found. Three patients with either TGFBR1 or TGFBR2 abnormality did not fulfill the Ghent criteria, but expressed some overlapping features of MFS and Loeys-Dietz syndrome (LDS). In the remaining 19 patients, either of the genes did not show any abnormalities. This study indicated that FBN1 mutations were predominant in MFS but TGFBRs defects may account for approximately 5-10% of patients with the syndrome.
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Affiliation(s)
- Haruya Sakai
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Japan
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62
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Tunçbilek E, Alanay Y. Congenital contractural arachnodactyly (Beals syndrome). Orphanet J Rare Dis 2006; 1:20. [PMID: 16740166 PMCID: PMC1524931 DOI: 10.1186/1750-1172-1-20] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2006] [Accepted: 06/01/2006] [Indexed: 11/30/2022] Open
Abstract
Congenital contractural arachnodactyly (Beals syndrome) is an autosomal dominantly inherited connective tissue disorder characterized by multiple flexion contractures, arachnodactyly, severe kyphoscoliosis, abnormal pinnae and muscular hypoplasia. It is caused by a mutation in FBN2 gene on chromosome 5q23. Although the clinical features can be similar to Marfan syndrome (MFS), multiple joint contractures (especially elbow, knee and finger joints), and crumpled ears in the absence of significant aortic root dilatation are characteristic of Beals syndrome and rarely found in Marfan syndrome. The incidence of CCA is unknown and its prevalence is difficult to estimate considering the overlap in phenotype with MFS; the number of patients reported has increased following the identification of FBN2 mutation. Molecular prenatal diagnosis is possible. Ultrasound imaging may be used to demonstrate joint contractures and hypokinesia in suspected cases. Management of children with CCA is symptomatic. Spontaneous improvement in camptodactyly and contractures is observed but residual camptodactyly always remains. Early intervention for scoliosis can prevent morbidity later in life. Cardiac evaluation and ophthalmologic evaluations are recommended.
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Affiliation(s)
- Ergül Tunçbilek
- Clinical Genetics Unit, Department of Pediatrics, Faculty of Medicine, Hacettepe University, 06100, Sihhiye, Ankara, Turkey
| | - Yasemin Alanay
- Clinical Genetics Unit, Department of Pediatrics, Faculty of Medicine, Hacettepe University, 06100, Sihhiye, Ankara, Turkey
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63
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Daeubler BF, Carrel T, Kujawski T, Schnyder A, Zurmuehle P, Vock P, Anderson SE. Alterations of the thoracic spine in Marfan's syndrome. AJR Am J Roentgenol 2006; 186:1246-51. [PMID: 16632713 DOI: 10.2214/ajr.05.0071] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE The purpose of this study was to determine if the thoracic vertebral elements are altered in patients with Marfan's syndrome. MATERIALS AND METHODS Thirty patients underwent helical CT of the thorax because of suspected thoracic aortic dilatation and acute dissection. Thirteen had Marfan's syndrome and 17 did not. Two reviewers, unaware of the final diagnosis, evaluated the images by consensus for laminar thickness, foraminal width, dural sac ratios, and vertebral scalloping for T2-T12. RESULTS At T9-T12, dural sac ratios at the midcorpus level (p = 0.031) and foraminal width (p = 0.0124) were significantly greater in the patients with Marfan's syndrome than in the patients without. Dural sac ratios at lower endplate levels (p = 0.0685), laminar thickness (p = 0.951), and vertebral scalloping (p = 0.24) were not significantly greater in the patients with Marfan's syndrome than in the patients without. CONCLUSION Because the phenotypic expression of Marfan's syndrome is variable, information on the spine from thoracic studies in combination with major criteria may be helpful clinically.
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Affiliation(s)
- Bernd F Daeubler
- Department of Radiology, University Hospital, Inselspital, Freiburgstrasse 20, Berne CH-3010, Switzerland.
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64
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Snape KMG, Fahey MC, McGillivray G, Gupta P, Milewicz DM, Delatycki MB. Long-term survival in a child with severe congenital contractural arachnodactyly, autism and severe intellectual disability. Clin Dysmorphol 2006; 15:95-9. [PMID: 16531736 DOI: 10.1097/01.mcd.0000203633.86190.2d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The severe form of congenital contractural arachnodactyly is usually associated with early mortality due to multisystem complications. Here, we report a 9-year-old male child with severe skeletal manifestations of congenital contractural arachnodactyly. He had none of the cardiovascular or gastrointestinal features that have been described in severe congenital contractural arachnodactyly. He had profound intellectual disability with autism. All exons of FBN2, the gene associated with congenital contractural arachnodactyly, were sequenced and no disease-causing mutation was found. When severe congenital contractural arachnodactyly is diagnosed in the newborn period, parents need to be aware that long-term survival is possible, particularly if no significant extraskeletal complications are present, and that significant neurodevelopmental delay may occur.
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Affiliation(s)
- Katie M G Snape
- Bruce Lefroy Centre for Genetic Health Research, Murdoch Childrens Research Institute, Parkville, Victoria, Australia
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65
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Robinson PN, Arteaga-Solis E, Baldock C, Collod-Béroud G, Booms P, De Paepe A, Dietz HC, Guo G, Handford PA, Judge DP, Kielty CM, Loeys B, Milewicz DM, Ney A, Ramirez F, Reinhardt DP, Tiedemann K, Whiteman P, Godfrey M. The molecular genetics of Marfan syndrome and related disorders. J Med Genet 2006; 43:769-87. [PMID: 16571647 PMCID: PMC2563177 DOI: 10.1136/jmg.2005.039669] [Citation(s) in RCA: 276] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Marfan syndrome (MFS), a relatively common autosomal dominant hereditary disorder of connective tissue with prominent manifestations in the skeletal, ocular, and cardiovascular systems, is caused by mutations in the gene for fibrillin-1 (FBN1). The leading cause of premature death in untreated individuals with MFS is acute aortic dissection, which often follows a period of progressive dilatation of the ascending aorta. Recent research on the molecular physiology of fibrillin and the pathophysiology of MFS and related disorders has changed our understanding of this disorder by demonstrating changes in growth factor signalling and in matrix-cell interactions. The purpose of this review is to provide a comprehensive overview of recent advances in the molecular biology of fibrillin and fibrillin-rich microfibrils. Mutations in FBN1 and other genes found in MFS and related disorders will be discussed, and novel concepts concerning the complex and multiple mechanisms of the pathogenesis of MFS will be explained.
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Affiliation(s)
- P N Robinson
- Institute of Medical Genetics, Charité University Hospital, Humboldt University, Augustenburger Platz 1, 13353 Berlin, Germany.
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66
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Hubmacher D, Tiedemann K, Reinhardt DP. Fibrillins: from biogenesis of microfibrils to signaling functions. Curr Top Dev Biol 2006; 75:93-123. [PMID: 16984811 DOI: 10.1016/s0070-2153(06)75004-9] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Fibrillins are large proteins that form extracellular microfibril suprastructures ubiquitously found in elastic and nonelastic tissues. Mutations in fibrillin-1 and -2 lead to a number of heritable connective tissue disorders generally termed fibrillinopathies. Clinical symptoms in fibrillinopathies manifest in the skeletal, ocular, and cardiovascular systems and highlight the importance of fibrillins in development and homeostasis of tissues and organs, including blood vessels, bone, and eye. Microfibrils appear to have dual roles in (1) conferring mechanical stability and limited elasticity to tissues, and (2) modulating the activity of growth factors of the transforming growth factor beta (TGF-beta) superfamily. This chapter's focus is on the biogenesis of microfibrils, developmental expression patterns of fibrillins, signaling functions of microfibrils, and mouse models deficient in fibrillins.
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Affiliation(s)
- Dirk Hubmacher
- Department of Anatomy and Cell Biology, Faculty of Medicine, McGill University Montreal, Quebec, H3A 2B2, Canada
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67
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Cain SA, Morgan A, Sherratt MJ, Ball SG, Shuttleworth CA, Kielty CM. Proteomic analysis of fibrillin-rich microfibrils. Proteomics 2006; 6:111-22. [PMID: 16302274 DOI: 10.1002/pmic.200401340] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
MS has been used to investigate the composition of fibrillin-rich microfibrils from non-elastic and elastic tissues, and to compare fibrillin-1 tryptic fingerprints derived from whole zonules, microfibrils and recombinant fibrillin-1. In all microfibril preparations, fibrillin-1 was abundant and the only fibrillin isoform. MAGP-1 was the only other microfibril-associated molecule. gamma-Crystallin co-purified with zonular microfibrils, so this association may contribute to ciliary zonule anchorage to lens. Recombinant fibrillin-1 tryptic peptides mapped throughout the molecule and included virtually all predicted peptides except for those larger than 4.5 kDa, smaller than 600 Da or post-translationally modified. In contrast, fewer microfibril tryptic fibrillin-1 peptides were detected, although they were derived from domains throughout the molecule and included two peptides after the C-terminal furin processing site. Several microfibril-derived N- and C-terminal domains never yielded any peptides, while tryptic peptides from other domains yielded numerous peptides, suggesting that some tissue microfibril features are retained after trypsinisation. This first MS analysis of a purified extracellular matrix assembly has provided new insights into microfibril composition and fibrillin-1 organisation within them.
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Affiliation(s)
- Stuart A Cain
- Wellcome Trust Centre for Cell-Matrix Research, Manchester, UK
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68
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Abstract
Tendons and ligaments (T/L) are very similar fibrous tissues that respectively connect muscle to bone and bone to bone. They are comprised of fibroblasts that produce large amounts of extra-cellular matrix, resulting in a dense and hypocellular structure. The complex molecular organization of T/L, together with high water content, are responsible for their viscoelastic properties, hence insuring their mechanical function. We will first review recent work on tendon embryology and discuss ligament formation, which has been less documented. We will next summarize our current knowledge of T/L molecular architecture, alterations of which are a major cause for disease. We will finally focus on T/L repair after injury and on genetic diseases responsible for T/L defects.
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Affiliation(s)
- Samuel Tozer
- Centre National de la Recherche Scientifique (CNRS) UMR7622, Paris, France
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69
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Pannu H, Tran-Fadulu V, Milewicz DM. Genetic basis of thoracic aortic aneurysms and aortic dissections. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2005; 139C:10-6. [PMID: 16273536 DOI: 10.1002/ajmg.c.30069] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Ascending thoracic aortic aneurysms leading to type A dissections (TAAD) can occur in association with a genetic syndrome, such as Marfan syndrome (MFS), or as an autosomal dominant disorder in the absence of syndromic features, termed familial TAAD. Familial TAAD demonstrates genetic heterogeneity, and linkage studies have identified three TAAD loci at 5q13-14 (TAAD1), 11q23 (FAA1), and 3p24-25 (TAAD2). The underlying genetic heterogeneity of TAAD is reflected in the phenotypic variation associated with familial TAAD with respect to age of onset, progression, penetrance, and association with additional cardiac and vascular features. Recently, mutations in the TGFBR2 gene have been identified as the cause of disease linked to the TAAD2 locus, supporting the hypothesis that dysregulation of TGFbeta signaling is a mechanism leading to aneurysms and dissections. The recent identification of the TGFbeta pathway as a key target in the molecular pathogenesis of TAAD has opened new avenues for future genetic and therapeutic research.
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Affiliation(s)
- Hariyadarshi Pannu
- Division of Medical Genetics, Department of Internal Medicine, University of Texas Medical School, Houston, USA
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70
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Tiedemann K, Sasaki T, Gustafsson E, Göhring W, Bätge B, Notbohm H, Timpl R, Wedel T, Schlötzer-Schrehardt U, Reinhardt DP. Microfibrils at basement membrane zones interact with perlecan via fibrillin-1. J Biol Chem 2005; 280:11404-12. [PMID: 15657057 DOI: 10.1074/jbc.m409882200] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mutational defects in fibrillin-rich microfibrils give rise to a number of heritable connective tissue disorders, generally termed microfibrillopathies. To understand the pathogenesis of these microfibrillopathies, it is important to elucidate the supramolecular composition of microfibrils and their interaction properties with extracellular matrix components. Here we demonstrate that the proteoglycan perlecan is an associated component of microfibrils typically close to basement membrane zones. Double immunofluorescence studies demonstrate colocalization of fibrillin-1, the major backbone component of microfibrils, with perlecan in fibroblast cultures as well as in dermal and ocular tissues. Double immunogold labeling further confirms colocalization of perlecan to microfibrils in various tissues at the ultrastructural level. Extraction studies revealed that perlecan is not covalently associated with microfibrils. High affinity interactions between fibrillin-1 and perlecan were found by kinetic binding studies with dissociation constants in the low nanomolar range. A detailed mapping study of the interaction epitopes by solid phase binding assays primarily revealed interactions of perlecan domains I and II with a central region of fibrillin-1. Analysis of perlecan null embryos showed less microfibrils at the dermal-epidermal junction as compared with wild-type littermates. The data presented indicate a functional significance for perlecan in anchoring microfibrils to basement membranes and in the biogenesis of microfibrils.
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Affiliation(s)
- Kerstin Tiedemann
- Department of Medical Molecular Biology, University of Lübeck, 23538 Lübeck, Germany
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71
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Garcia-Miñaur S, Ramsay J, Grace E, Minns RA, Myles LM, FitzPatrick DR. Interstitial deletion of the long arm of chromosome 5 in a boy with multiple congenital anomalies and mental retardation: Molecular characterization of the deleted region to 5q22.3q23.3. Am J Med Genet A 2004; 132A:402-10. [PMID: 15742475 DOI: 10.1002/ajmg.a.30421] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Interstitial deletions of the middle portion of the long arm of chromosome 5 are relatively rare. So far, only 36 cases have been reported. Because of the repetitive banding pattern of this region, the extent and localization of the deleted segment has not been well characterized in the majority of reported cases. This has complicated attempts to establish a definite karyotype-phenotype correlation. We report a further case with a de novo interstitial deletion of the region 5q?15 to 5q?22 identified by standard karyotype analysis. The proband presented with failure to thrive, developmental delay, distinct craniofacial dysmorphic features, and associated structural anomalies (amongst them cleft palate, iris colobomata, and horseshoe kidney, which have previously been reported in 5q deletion cases). In addition, this child had an Arnold-Chiari type I malformation that required surgical decompression. FISH studies using BAC clones spanning the 5q15 to 5q22 region revealed that these were all present in both homologues. Use of more distal clones allowed delineation of the deleted region to 5q22.3q23.3 and to narrow down the breakpoints to approximately 200 kb. The 14 Mb deleted region contains about 60 genes but, with the possible exception of FBN2 and DMXL1, there are no obvious candidate genes for the specific components of the phenotype. This case illustrates the discrepancy between cytogenetic and molecular techniques in trying to delineate 5q interstitial deletions. Molecular studies need to be performed on these patients, to establish genotype-phenotype correlation and to understand the role and influence of genes in this region.
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Affiliation(s)
- Sixto Garcia-Miñaur
- South East of Scotland Genetics Service, Western General Hospital, Edinburgh, United Kingdom.
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72
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Corson GM, Charbonneau NL, Keene DR, Sakai LY. Differential expression of fibrillin-3 adds to microfibril variety in human and avian, but not rodent, connective tissues. Genomics 2004; 83:461-72. [PMID: 14962672 DOI: 10.1016/j.ygeno.2003.08.023] [Citation(s) in RCA: 143] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2003] [Revised: 07/24/2003] [Accepted: 08/25/2003] [Indexed: 11/21/2022]
Abstract
The human genome contains three fibrillins: FBN1 and FBN2, both well characterized, and FBN3, reported only as a cDNA sequence. Like FBN2, the highest expression levels of FBN3 were found in fetal tissues, with only low levels in postnatal tissues. Immunolocalization demonstrated fibrillin-3 in extracellular microfibrils abundant in developing skeletal elements, skin, lung, kidney, and skeletal muscle. Unlike the other two fibrillins, FBN3 expression is high in brain, and FBN3 is alternatively spliced, removing the exon encoding cbEGF2. Like FBN1, FBN3 contains three alternate exons in the 5' UTR. While FBN3 orthologs were identified in cow and chicken, Fbn3 appears to have been inactivated in the mouse genome, perhaps during chromosome fission events. Located on chromosome 19p13.3-13.2, FBN3 is a candidate gene for Weill-Marchesani syndrome.
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Affiliation(s)
- Glen M Corson
- Shriners Hospital for Children, Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, OR 97201, USA
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73
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Abstract
BACKGROUND In 1968, De Barsy reported on a girl exhibiting an aged aspect, 'dwarfism, oligophrenia, and degeneration of the elastic tissue in cornea and skin'. The disorder was recognized as a subgroup of cutis laxa syndrome and termed De Barsy-Moens-Dierckx syndrome. The pathogenesis of the disorder is unknown. METHODS To improve the comprehension of the pathogenetic mechanisms involved in the De Barsy syndrome, we performed an ultrastructural, morphometric, immunocytochemical study on a skin biopsy of a boy with the De Barsy phenotype, who has been clinically followed for 12 years from birth. Moreover, the lysyl oxidase activity was measured on skin fibroblasts cultured in vitro. RESULTS Light and electron microscopy, morphometry, and immunocytochemical observations showed a significant reduction of the elastic fibers in the papillary and in the reticular dermis of patient compared to an age-matched control (p < 0.05). By contrast, the collagen structure, content, and the distribution were normal, as well as lysyl oxidase activity in the medium of in vitro fibroblasts (12,323 DPM/10(6) cells). The immunoreaction for antibodies recognizing fibrillin-1, neutrophilic elastase, and tumor necrosis factor-alpha was stronger, whereas that for antibodies against transforming growth factor-beta was less pronounced in the dermis of the De Barsy boy compared to control. CONCLUSIONS Clinical, phenotypic, and structural data were consistent with the diagnosis of De Barsy syndrome. This is the first case described in Italy. Clinical and structural data confirm that the elastic component is mostly affected in this disorder. Moreover, ultrastructural and immunochemical findings suggest that both elastic fiber degradative and very likely synthetic processes are involved.
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Affiliation(s)
- Deanna Guerra
- Department of Biomedical Sciences, General Hospital, University of Modena and Reggio Emilia, Modena, Italy.
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74
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Revencu N, Quenum G, Detaille T, Verellen G, De Paepe A, Verellen-Dumoulin C. Congenital diaphragmatic eventration and bilateral uretero-hydronephrosis in a patient with neonatal Marfan syndrome caused by a mutation in exon 25 of the FBN1 gene and review of the literature. Eur J Pediatr 2004; 163:33-7. [PMID: 14586646 DOI: 10.1007/s00431-003-1330-8] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2003] [Revised: 09/22/2003] [Accepted: 09/23/2003] [Indexed: 11/26/2022]
Abstract
UNLABELLED Neonatal Marfan syndrome, the most severe presentation of Marfan syndrome phenotypes (MIM 154700), is characterised mainly by joint contractures, arachnodactyly, loose skin, crumpled ears, severe atrioventricular valve dysfunction and pulmonary emphysema. Death usually occurs within the first 2 years of life from congestive heart failure. We describe here a newborn male with many typical characteristics of neonatal Marfan syndrome associated with a diaphragmatic eventration and a bilateral uretero-hydronephrosis with bladder dilatation. He died from cardiac failure due to severe tricuspid and mitral regurgitation at 62 h of age. CONCLUSION Molecular analysis showed a heterozygous missense mutation at nucleotide 3165 (3165T>G) in exon 25 of the FBN1 gene, resulting in the substitution of cysteine for tryptophan (C1055W).
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Affiliation(s)
- Nicole Revencu
- Center for Human Genetics and Medical Genetics Unit, Cliniques universitaires Saint-Luc and Université catholique de Louvain, Av. Mounier 5220, 1200 Brussels, Belgium.
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75
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Charbonneau NL, Ono RN, Corson GM, Keene DR, Sakai LY. Fine tuning of growth factor signals depends on fibrillin microfibril networks. ACTA ACUST UNITED AC 2004; 72:37-50. [PMID: 15054903 DOI: 10.1002/bdrc.20000] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Growth factors, potent regulators of cell differentiation, tissue morphogenesis, tissue homeostasis, and cellular response to injury, reside in the extracellular matrix. Genetic evidence in humans and mice as well as biochemical data implicate fibrillins and LTBPs in the extracellular control of TGFbeta and BMP signaling. Fibrillins and LTBPs form tissue-specific and temporally regulated microfibril networks. In the developing embryo, three fibrillins and four LTBPs contribute molecular heterogeneity to microfibril networks, and provide different templates upon which TGFbeta-related growth factors can be positioned. By accommodating this molecular heterogeneity, microfibril architecture can orchestrate a variety of different signals in very specific tissue locations. Human fibrillinopathies display a broad phenotypic spectrum from tall to short stature, from hypermobile joints to joint contractures and stiffness, and from severe to mild or no cardiovascular manifestations. A spectrum of growth factor dysregulation may be caused by differential effects of mutations in fibrillins on microfibril architecture, thus altering appropriate targeting or positioning of growth factors within microfibril networks. Growth factor dysregulation may help to explain the broad phenotypic spectrum of the fibrillinopathies.
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Affiliation(s)
- Noe L Charbonneau
- Shriners Hospital for Children, and the Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon
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76
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Ritty TM, Roth R, Heuser JE. Tendon cell array isolation reveals a previously unknown fibrillin-2-containing macromolecular assembly. Structure 2003; 11:1179-88. [PMID: 12962636 DOI: 10.1016/s0969-2126(03)00181-3] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Within tendon, between collagen fascicles, cells are organized in linear arrays surrounded by a specialized environment of extracellular matrix (ECM) proteins that are largely unidentified. Our goal was to identify interfascicular, pericellular ECM components and provide additional resolution to the organization of the pericellular matrix. To this end, we employed a combination of enzymatic digestion, mechanical disruption, and differential sedimentation to demonstrate for the first time that it possible to liberate living linear tendon cell arrays from whole tendon. Here, we identify type VI collagen, versican, and fibrillin-2 as components of the immediate pericellular ECM of linearly arrayed tendon cells. Additionally, a unique fibrillin-2-containing macromolecular assembly is described in detail for the first time. This new structure is unlike any previously described fibrillin-containing macromolecular assembly. Having a largely constant diameter, it runs axially along tendon cell arrays and can exceed 1000 microm in length.
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Affiliation(s)
- Timothy M Ritty
- Department of Orthopaedic Surgery at Barnes-Jewish Hospital, Washington University School of Medicine, St. Louis, MO 63110, USA.
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77
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Abstract
The major diseases affecting the aorta are aortic aneurysms and dissections, which are classified based on anatomic location. Diseases affecting the ascending aorta, such as thoracic aortic aneurysms and type I and II dissections, are primarily associated with medial necrosis on pathologic examination. Medial necrosis is characterized by fragmentation and loss of elastic fibers, loss of smooth muscle cells, and interstitial collections of collagenous tissue and basophilic ground substance. Medial necrosis occurs as part of the normal aging of the aorta but is accelerated by other conditions, including hypertension and genetic alterations that predispose persons to these aortic diseases. The etiologies of many of the genetic syndromes, such as Marfan syndrome, that predispose persons to thoracic aortic aneurysms and dissections are understood. Studies are just beginning to elucidate the genes that predispose persons without known syndromes to these aortic diseases, and a major locus for this condition, termed the TAAD1 locus, has been mapped to 5q13-14. Future characterization of this gene and others will enhance the ability to determine persons at risk for aortic aneurysms and dissections and will define molecular mechanisms involved in the pathogenesis of this disorder.
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Affiliation(s)
- Sumera N Hasham
- Division of Medical Genetics, Department of Internal Medicine, The University of Texas Medical School at Houston, 6431 Fannin, Houston, TX 77030, USA
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78
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Kölble N, Wisser J, Babcock D, Maslen C, Huch R, Steinmann B. Prenatal ultrasound findings in a fetus with congenital contractural arachnodactyly. ULTRASOUND IN OBSTETRICS & GYNECOLOGY : THE OFFICIAL JOURNAL OF THE INTERNATIONAL SOCIETY OF ULTRASOUND IN OBSTETRICS AND GYNECOLOGY 2002; 20:395-399. [PMID: 12383326 DOI: 10.1046/j.1469-0705.2002.00819.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Congenital contractural arachnodactyly (CCA) or Beals-Hecht syndrome is an autosomal dominant disorder caused by mutations in the fibrillin-2 (FBN2) gene. The principal features of CCA are a marfanoid habitus, multiple congenital contractures, camptodactyly, arachnodactyly, kyphoscoliosis, muscular hypoplasia, and external ear malformations. Our case is the first that shows typical sonographic signs in a fetus at 25 weeks' gestation with molecular genetically verified CCA in a large family with many members affected over four generations. This demonstrates that CCA can be detected prenatally by non-invasive ultrasonography. The importance of confirmation of CCA by means of DNA sequence analysis of the FBN2 gene is stressed.
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Affiliation(s)
- N Kölble
- Unit of Perinatal Physiology, Department of Obstetrics, University Hospital, Zurich, Switzerland.
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79
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Abstract
The predominant influences on fetal growth are maternal and placental factors. Post-natal growth is regulated by a complex interaction between genetic, environmental and hormonal influences. The role of the growth hormone insulin-like growth factor (GH-IGF) system is explored, including the emerging role of IGF-2 in fetal growth. Increasing understanding of the genetics of overgrowth and short stature syndromes is contributing greatly to basic understanding of growth regulation. A range of prenatal overgrowth syndromes is discussed, including those associated with neonatal hyperinsulinism and hypoglycaemia.Post-natal overgrowth may be caused by a diverse range of normal variant conditions, endocrine disorders, chromosomal abnormalities and other genetic syndromes. An approach to diagnosis is presented and major conditions discussed in detail. Sex-steroid therapy for height limitation continues to be a controversial area with uncertainty about height prediction, benefits achieved and possible long-term side-effects.
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Affiliation(s)
- Geoffrey Ambler
- The Children's Hospital at Westmead, Locked Bag 4001, Westmead, NSW, Australia
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