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Mian M, Tan J, Yong R, Williams R, Labrinidis A, Anderson PJ, Ranjitkar S. Craniofacial Phenomics: Three-Dimensional Assessment of the Size and Shape of Cranial and Dentofacial Structures. Methods Mol Biol 2022; 2403:107-127. [PMID: 34913120 DOI: 10.1007/978-1-0716-1847-9_9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Craniofacial phenomics has opened up numerous opportunities to correlate genetic and epigenetic factors to craniofacial phenotypes in order to improve our understanding of growth and development in health and disease. Three-dimensional (3D) imaging has played a key role in advancing craniofacial phenomics by facilitating highly sensitive and specific characterizations of craniofacial and dental morphology. Here we describe the use of micro-computed tomography (micro-CT) to image the murine craniofacial complex, followed by surface reconstruction for traditional morphometric analyses. We also describe the application of geometric morphometrics, based on Generalized Procrustes Analysis, for use in human premolars. These principles are interchangeable between various vertebrate species, and between various surface imaging techniques (including micro-CT and 3D surface scanners), offering a high level of versatility and precision for extensive phenotyping of the entire craniofacial complex.
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Affiliation(s)
- Mustafa Mian
- Adelaide Dental School, The University of Adelaide, Adelaide, SA, Australia
| | - Jenny Tan
- Adelaide Dental School, The University of Adelaide, Adelaide, SA, Australia
| | - Robin Yong
- Adelaide Dental School, The University of Adelaide, Adelaide, SA, Australia
| | - Ruth Williams
- Adelaide Microscopy, The University of Adelaide, Adelaide, SA, Australia
| | - Agatha Labrinidis
- Adelaide Microscopy, The University of Adelaide, Adelaide, SA, Australia
| | - Peter J Anderson
- Adelaide Dental School, The University of Adelaide, Adelaide, SA, Australia
- Australian Craniofacial Unit, Women's and Children's Hospital, North Adelaide, SA, Australia
- South Australian Health and Medical Research Institute (SAHMRI), Adelaide, SA, Australia
| | - Sarbin Ranjitkar
- Adelaide Dental School, The University of Adelaide, Adelaide, SA, Australia.
- Department of Dentistry and Oral Health, La Trobe Rural Health School, La Trobe University, Bendigo, VIC, Australia.
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Ho R, Hegele RA. Complex effects of laminopathy mutations on nuclear structure and function. Clin Genet 2018; 95:199-209. [DOI: 10.1111/cge.13455] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 09/26/2018] [Accepted: 09/27/2018] [Indexed: 12/12/2022]
Affiliation(s)
- Rosettia Ho
- Departments of Biochemistry and Medicine, and Robarts Research Institute; Schulich School of Medicine and Dentistry, Western University; London Ontario Canada
| | - Robert A. Hegele
- Departments of Biochemistry and Medicine, and Robarts Research Institute; Schulich School of Medicine and Dentistry, Western University; London Ontario Canada
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Phenomics research on coronary heart disease based on human phenotype ontology. BIOMED RESEARCH INTERNATIONAL 2015; 2014:240284. [PMID: 25610858 PMCID: PMC4279366 DOI: 10.1155/2014/240284] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Revised: 08/28/2014] [Accepted: 09/12/2014] [Indexed: 11/17/2022]
Abstract
The characteristics of holistic, dynamics, complexity, and spatial and temporal features enable "Omics" and theories of TCM to interlink with each other. HPO, namely, "characterization," can be understood as a sorting and generalization of the manifestations shown by people with diseases on the basis of the phenomics. Syndrome is the overall "manifestation" of human body pathological and physiological changes expressed by four diagnostic methods' information. The four diagnostic methods' data could be the most objective and direct manifestations of human body under morbid conditions. In this aspect, it is consistent with the connation of "characterization." Meanwhile, the four diagnostic methods' data also equip us with features of characterization in HPO. In our study, we compared 107 pieces of four diagnostic methods' information with the "characterization database" to further analyze data of four diagnostic methods' characterization in accordance with the common characteristics of four diagnostic methods' information and characterization and integrated 107 pieces of four diagnostic methods' data to relevant items in HPO and finished the expansion of characterization information in HPO.
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Quellec G, Russell SR, Seddon JM, Reynolds R, Scheetz T, Mahajan VB, Stone EM, Abràmoff MD. Automated discovery and quantification of image-based complex phenotypes: a twin study of drusen phenotypes in age-related macular degeneration. Invest Ophthalmol Vis Sci 2011; 52:9195-206. [PMID: 22039249 PMCID: PMC3302481 DOI: 10.1167/iovs.10-6793] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2011] [Revised: 06/20/2011] [Accepted: 10/11/2011] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Determining the relationships between phenotype and genotype of many disorders can improve clinical diagnoses, identify disease mechanisms, and enhance therapy. Most genetic disorders result from interaction of many genes that obscure the discovery of such relationships. The hypothesis for this study was that image analysis has the potential to enable formalized discovery of new visible phenotypes. It was tested in twins affected with age-related macular degeneration (AMD). METHODS Fundus images from 43 monozygotic (MZ) and 32 dizygotic (DZ) twin pairs with AMD were examined. First, soft and hard drusen were segmented. Then newly defined phenotypes were identified by using drusen distribution statistics that significantly separate MZ from DZ twins. The ACE model was used to identify the contributions of additive genetic (A), common environmental (C), and nonshared environmental (E) effects on drusen distribution phenotypes. RESULTS Four drusen distribution characteristics significantly separated MZ from DZ twin pairs. One encoded the quantity, and the remaining three encoded the spatial distribution of drusen, achieving a zygosity prediction accuracy of 76%, 74%, 68%, and 68%. Three of the four phenotypes had a 55% to 77% genetic effect in an AE model, and the fourth phenotype showed a nonshared environmental effect (E model). CONCLUSIONS Computational discovery of genetically determined features can reveal quantifiable AMD phenotypes that are genetically determined without explicitly linking them to specific genes. In addition, it can identify phenotypes that appear to result predominantly from environmental exposure. The approach is rapid and unbiased, suitable for large datasets, and can be used to reveal unknown phenotype-genotype relationships.
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Affiliation(s)
- Gwenole Quellec
- From the Institute for Vision Research, University of Iowa Hospitals and Clinics, Iowa City, Iowa
- the Departments of Biomedical Engineering and
| | - Stephen R. Russell
- From the Institute for Vision Research, University of Iowa Hospitals and Clinics, Iowa City, Iowa
- the Carver Family Center for Macular Degeneration, and
| | - Johanna M. Seddon
- the Ophthalmic Epidemiology and Genetics Service, Tufts Medical Center, Boston, Massachusetts
- Tufts University School of Medicine, Boston, Massachusetts; and
| | - Robyn Reynolds
- the Ophthalmic Epidemiology and Genetics Service, Tufts Medical Center, Boston, Massachusetts
| | - Todd Scheetz
- the Departments of Biomedical Engineering and
- Electrical and Computer Engineering
| | - Vinit B. Mahajan
- From the Institute for Vision Research, University of Iowa Hospitals and Clinics, Iowa City, Iowa
| | - Edwin M. Stone
- From the Institute for Vision Research, University of Iowa Hospitals and Clinics, Iowa City, Iowa
- the Carver Family Center for Macular Degeneration, and
- the Howard Hughes Medical Institute, University of Iowa, Iowa City, Iowa
| | - Michael D. Abràmoff
- From the Institute for Vision Research, University of Iowa Hospitals and Clinics, Iowa City, Iowa
- the Departments of Biomedical Engineering and
- Electrical and Computer Engineering
- the Carver Family Center for Macular Degeneration, and
- the Department of Veterans Affairs, Center of Excellence for Prevention and Treatment of Visual Loss, Iowa City VA Medical Center, Iowa City, Iowa
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Beyond membrane channelopathies: alternative mechanisms underlying complex human disease. Acta Pharmacol Sin 2011; 32:798-804. [PMID: 21642948 DOI: 10.1038/aps.2011.34] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Over the past fifteen years, our understanding of the molecular mechanisms underlying human disease has flourished in large part due to the discovery of gene mutations linked with membrane ion channels and transporters. In fact, ion channel defects ("channelopathies" - the focus of this review series) have been associated with a spectrum of serious human disease phenotypes including cystic fibrosis, cardiac arrhythmia, diabetes, skeletal muscle defects, and neurological disorders. However, we now know that human disease, particularly excitable cell disease, may be caused by defects in non-ion channel polypeptides including in cellular components residing well beneath the plasma membrane. For example, over the past few years, a new class of potentially fatal cardiac arrhythmias has been linked with cytoplasmic proteins that include sub-membrane adapters such as ankyrin-B (ANK2), ankyrin-G (ANK3), and alpha-1 syntrophin, membrane coat proteins including caveolin-3 (CAV3), signaling platforms including yotiao (AKAP9), and cardiac enzymes (GPD1L). The focus of this review is to detail the exciting role of lamins, yet another class of gene products that have provided elegant new insight into human disease.
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Laminopathies: the molecular background of the disease and the prospects for its treatment. Cell Mol Biol Lett 2010; 16:114-48. [PMID: 21225470 PMCID: PMC6275778 DOI: 10.2478/s11658-010-0038-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2010] [Accepted: 12/13/2010] [Indexed: 02/06/2023] Open
Abstract
Laminopathies are rare human degenerative disorders with a wide spectrum of clinical phenotypes, associated with defects in the main protein components of the nuclear envelope, mostly in the lamins. They include systemic disorders and tissue-restricted diseases. Scientists have been trying to explain the pathogenesis of laminopathies and find an efficient method for treatment for many years. In this review, we discuss the current state of knowledge about laminopathies, the molecular mechanisms behind the development of particular phenotypes, and the prospects for stem cell and/or gene therapy treatments.
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Saha B, Lessel D, Hisama FM, Leistritz DF, Friedrich K, Martin GM, Kubisch C, Oshima J. A Novel LMNA Mutation Causes Altered Nuclear Morphology and Symptoms of Familial Partial Lipodystrophy (Dunnigan Variety) with Progeroid Features. Mol Syndromol 2010; 1:127-132. [PMID: 21031082 DOI: 10.1159/000320166] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2010] [Accepted: 08/01/2010] [Indexed: 11/19/2022] Open
Abstract
Dunnigan-type partial lipodystrophy (familial partial lipodystrophy, Dunnigan variety, FPLD2) can be caused by LMNA mutations. We identified a novel heterozygous LMNA mutation, P485R, in a patient referred to the International Registry of Werner Syndrome because of features consistent with that of progeroid disorder but who was wild type at the WRN locus. The novel mutation is located 2 amino acids away from the canonical FPLD mutations in exon 8 of the LMNA gene. Immunocytochemical analysis revealed abnormal nuclear morphology characteristic of laminopathies within primary fibroblast cultures, but not in a lymphoblastoid cell line, in keeping with previous observations. Our findings indicate that FPLD2 should be considered in the differential diagnosis of the Werner syndrome.
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Affiliation(s)
- B Saha
- Department of Pathology, University of Washington, Seattle, Wash., USA
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Berretta R, Moscato P. Cancer biomarker discovery: the entropic hallmark. PLoS One 2010; 5:e12262. [PMID: 20805891 PMCID: PMC2923618 DOI: 10.1371/journal.pone.0012262] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2009] [Accepted: 06/26/2010] [Indexed: 12/29/2022] Open
Abstract
Background It is a commonly accepted belief that cancer cells modify their transcriptional state during the progression of the disease. We propose that the progression of cancer cells towards malignant phenotypes can be efficiently tracked using high-throughput technologies that follow the gradual changes observed in the gene expression profiles by employing Shannon's mathematical theory of communication. Methods based on Information Theory can then quantify the divergence of cancer cells' transcriptional profiles from those of normally appearing cells of the originating tissues. The relevance of the proposed methods can be evaluated using microarray datasets available in the public domain but the method is in principle applicable to other high-throughput methods. Methodology/Principal Findings Using melanoma and prostate cancer datasets we illustrate how it is possible to employ Shannon Entropy and the Jensen-Shannon divergence to trace the transcriptional changes progression of the disease. We establish how the variations of these two measures correlate with established biomarkers of cancer progression. The Information Theory measures allow us to identify novel biomarkers for both progressive and relatively more sudden transcriptional changes leading to malignant phenotypes. At the same time, the methodology was able to validate a large number of genes and processes that seem to be implicated in the progression of melanoma and prostate cancer. Conclusions/Significance We thus present a quantitative guiding rule, a new unifying hallmark of cancer: the cancer cell's transcriptome changes lead to measurable observed transitions of Normalized Shannon Entropy values (as measured by high-througput technologies). At the same time, tumor cells increment their divergence from the normal tissue profile increasing their disorder via creation of states that we might not directly measure. This unifying hallmark allows, via the the Jensen-Shannon divergence, to identify the arrow of time of the processes from the gene expression profiles, and helps to map the phenotypical and molecular hallmarks of specific cancer subtypes. The deep mathematical basis of the approach allows us to suggest that this principle is, hopefully, of general applicability for other diseases.
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Affiliation(s)
- Regina Berretta
- Centre for Bioinformatics, Biomarker Discovery and Information-Based Medicine, The University of Newcastle, Callaghan, New South Wales, Australia
- Information Based Medicine Program, Hunter Medical Research Institute, John Hunter Hospital, New Lambton Heights, New South Wales, Australia
| | - Pablo Moscato
- Centre for Bioinformatics, Biomarker Discovery and Information-Based Medicine, The University of Newcastle, Callaghan, New South Wales, Australia
- Information Based Medicine Program, Hunter Medical Research Institute, John Hunter Hospital, New Lambton Heights, New South Wales, Australia
- Australian Research Council Centre of Excellence in Bioinformatics, Callaghan, New South Wales, Australia
- * E-mail:
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A translational view of the genetics of lipodystrophy and ectopic fat deposition. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2010; 94:159-96. [PMID: 21036325 DOI: 10.1016/b978-0-12-375003-7.00006-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A wide range of lipodystrophy syndromes exist, each with varying clinical presentations, and yet cumulatively they underscore the importance of adipocyte biology in human metabolism. Loss of the ability to retain excess lipids in "classical" adipose tissue stores can lead to the overdevelopment of ectopic fat stores, often creating severe perturbations of both glucose and lipid homeostasis. Linkage analysis and candidate sequencing efforts have successfully identified responsible mutations for multiple forms of lipodystrophy. Recently, the reduction in the cost of DNA sequencing has resulted in discovery of many novel mutations within both known and novel loci. In this review, we present the steps involved in clinical characterization of a suspected lipodystrophy case, an overview of the clinical manifestations, molecular findings, and pathogenic basis of different forms of lipodystrophy, a discussion of therapeutic options for lipodystrophy patients, and an examination of genetic advances that will be used to identify additional pathogenic mechanisms.
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Omary MB. "IF-pathies": a broad spectrum of intermediate filament-associated diseases. J Clin Invest 2009; 119:1756-62. [PMID: 19587450 DOI: 10.1172/jci39894] [Citation(s) in RCA: 118] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Intermediate filaments (IFs) are encoded by the largest gene family among the three major cytoskeletal protein groups. Unique IF compliments are expressed in selective cell types, and this expression is reflected in their involvement, upon mutation, as a cause of or predisposition to more than 80 human tissue-specific diseases. This Review Series covers diseases and functional and structural aspects pertaining to IFs and highlights the molecular and functional consequences of IF-associated diseases (IF-pathies). Exciting challenges and opportunities face the IF field, including developing both a better understanding of the pathogenesis of IF-pathies and targeted therapeutic approaches.
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Affiliation(s)
- M Bishr Omary
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI 48109-5622, USA.
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Hegele RA, Pollex RL. Hypertriglyceridemia: phenomics and genomics. Mol Cell Biochem 2009; 326:35-43. [PMID: 19130180 DOI: 10.1007/s11010-008-0005-1] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2008] [Accepted: 12/15/2008] [Indexed: 11/30/2022]
Abstract
Hypertriglyceridemia is a common complex metabolic trait that is associated with increased atherosclerosis risk, presence of the metabolic syndrome and, with extreme elevation, increased risk of pancreatitis. Hierarchical cluster analysis using clinical and biochemical features of the Frederickson hyperlipoproteinemia types can generate hypotheses for molecular genetic studies. High throughput resequencing of individuals at the extremes of plasma triglyceride concentration has shown that both rare genetic variants with large effects and common genetic variants with moderate effects explain a relatively large proportion of variation. Very recent progress using high-density sets of genome-wide markers have identified additional genetic determinants of plasma triglyceride concentrations, albeit within largely normolipidemic subjects and with small effect sizes. Phenomic evaluation of patients with hypertriglyceridemia might help to clarify genotype-phenotype correlations and responses to interventions.
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Affiliation(s)
- Robert A Hegele
- Schulich School of Medicine and Dentistry, University of Western Ontario, London, ON, N6A 5K8, Canada.
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Heymann WR. Lipodystrophies and the metabolic syndrome. J Am Acad Dermatol 2009; 59:887-8. [PMID: 19119102 DOI: 10.1016/j.jaad.2008.03.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2008] [Revised: 03/17/2008] [Accepted: 03/21/2008] [Indexed: 10/21/2022]
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Toivola DM, Nakamichi I, Strnad P, Michie SA, Ghori N, Harada M, Zeh K, Oshima RG, Baribault H, Omary MB. Keratin overexpression levels correlate with the extent of spontaneous pancreatic injury. THE AMERICAN JOURNAL OF PATHOLOGY 2008; 172:882-92. [PMID: 18349119 DOI: 10.2353/ajpath.2008.070830] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Mutation of the adult hepatocyte keratins K8 and K18 predisposes to liver disease. In contrast, exocrine pancreas K8 and K18 are dispensable and are co-expressed with limited levels of membrane-proximal K19 and K20. Overexpression of mutant K18 or genetic ablation of K8 in mouse pancreas is well tolerated whereas overexpression of K8 causes spontaneous chronic pancreatitis. To better understand the effect of exocrine pancreatic keratin overexpression, we compared transgenic mice that overexpress K18, K8, or K8/K18, associated with minimal, modest, or large increases in keratin expression, respectively, with nontransgenic wild-type (WT) mice. Overexpression of the type-II keratin K8 up-regulated type-I keratins K18, K19, and K20 and generated K19/K20-containing neocytoplasmic typical or short filaments; however, overexpression of K18 had no effect on K8 levels. K8- and K18-overexpressing pancreata were histologically similar to WT, whereas K8/K18 pancreata displayed age-enhanced vacuolization and atrophy of the exocrine pancreas and exhibited keratin hyperphosphorylation. Zymogen granules in K8/K18 pancreata were 50% smaller and more dispersed than their normal apical concentration but were twice as numerous as in WT controls. Therefore, modest keratin overexpression has minor effects on the exocrine pancreas whereas significant keratin overexpression alters zymogen granule organization and causes aging-associated exocrine atrophy. Keratin absence or mutation is well tolerated after pancreatic but not liver injury, whereas excessive overexpression is toxic to the pancreas but not the liver when induced under basal conditions.
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Affiliation(s)
- Diana M Toivola
- Department of Medicine, Veterans Administration Palo Alto Health Care System, Palo Alto, CA, USA.
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Luft FC. The laminated hearts. J Mol Med (Berl) 2008; 86:243-5. [PMID: 18196211 DOI: 10.1007/s00109-007-0297-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2007] [Accepted: 12/17/2007] [Indexed: 11/30/2022]
Affiliation(s)
- Friedrich C Luft
- Experimental and Clinical Research Center, Franz Volhard Clinic at the Max Delbrück Center, Max Delbrück Center for Molecular Medicine, Berlin, Germany.
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Maraldi NM, Capanni C, Lattanzi G, Camozzi D, Facchini A, Manzoli FA. SREBP1 interaction with prelamin A forms: A pathogenic mechanism for lipodystrophic laminopathies. ACTA ACUST UNITED AC 2008; 48:209-23. [DOI: 10.1016/j.advenzreg.2007.11.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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Muñoz-Alarcón A, Pavlovic M, Wismar J, Schmitt B, Eriksson M, Kylsten P, Dushay MS. Characterization of lamin mutation phenotypes in Drosophila and comparison to human laminopathies. PLoS One 2007; 2:e532. [PMID: 17565385 PMCID: PMC1885830 DOI: 10.1371/journal.pone.0000532] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2007] [Accepted: 05/18/2007] [Indexed: 11/19/2022] Open
Abstract
Lamins are intermediate filament proteins that make up the nuclear lamina, a matrix underlying the nuclear membrane in all metazoan cells that is important for nuclear form and function. Vertebrate A-type lamins are expressed in differentiating cells, while B-type lamins are expressed ubiquitously. Drosophila has two lamin genes that are expressed in A- and B-type patterns, and it is assumed that similarly expressed lamins perform similar functions. However, Drosophila and vertebrate lamins are not orthologous, and their expression patterns evolved independently. It is therefore of interest to examine the effects of mutations in lamin genes. Mutations in the mammalian lamin A/C gene cause a range of diseases, collectively called laminopathies, that include muscular dystrophies and premature aging disorders. We compared the sequences of lamin genes from different species, and we have characterized larval and adult phenotypes in Drosophila bearing mutations in the lam gene that is expressed in the B-type pattern. Larvae move less and show subtle muscle defects, and surviving lam adults are flightless and walk like aged wild-type flies, suggesting that lam phenotypes might result from neuromuscular defects, premature aging, or both. The resemblance of Drosophila lam phenotypes to human laminopathies suggests that some lamin functions may be performed by differently expressed genes in flies and mammals. Such still-unknown functions thus would not be dependent on lamin gene expression pattern, suggesting the presence of other lamin functions that are expression dependent. Our results illustrate a complex interplay between lamin gene expression and function through evolution.
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Affiliation(s)
- Andrés Muñoz-Alarcón
- Department of Life Sciences, Södertörns högskola, Huddinge, Sweden
- Department of Biosciences and Nutrition, Karolinska Institute, Stockholm, Sweden
| | - Maja Pavlovic
- Department of Life Sciences, Södertörns högskola, Huddinge, Sweden
- Department of Biosciences and Nutrition, Karolinska Institute, Stockholm, Sweden
| | - Jasmine Wismar
- Max-Planck-Institut für Hirnforschung, Abteilung Neurochemie, Frankfurt, Germany
| | - Bertram Schmitt
- Max-Planck-Institut für Hirnforschung, Abteilung Neurochemie, Frankfurt, Germany
| | - Maria Eriksson
- Department of Biosciences and Nutrition, Karolinska Institute, Stockholm, Sweden
| | - Per Kylsten
- Department of Life Sciences, Södertörns högskola, Huddinge, Sweden
| | - Mitchell S. Dushay
- Department of Life Sciences, Södertörns högskola, Huddinge, Sweden
- Department of Comparative Physiology, EBC, Uppsala University, Uppsala, Sweden
- * To whom correspondence should be addressed. E-mail:
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