TY - JOUR A1 - Tayebi, Naeimeh A1 - Jamsheer, Aleksander A1 - Flöttmann, Ricarda A1 - Sowinska-Seidler, Anna A1 - Doelken, Sandra C. A1 - Oehl-Jaschkowitz, Barbara A1 - Hülsemann, Wiebke A1 - Habenicht, Rolf A1 - Klopocki, Eva A1 - Mundlos, Sefan A1 - Spielmann, Malte T1 - Deletions of exons with regulatory activity at the DYNC1I1 locus are associated with split-hand/split-foot malformation: array CGH screening of 134 unrelated families JF - Orphanet Journal of Rare Diseases N2 - Background: A growing number of non-coding regulatory mutations are being identified in congenital disease. Very recently also some exons of protein coding genes have been identified to act as tissue specific enhancer elements and were therefore termed exonic enhancers or "eExons". Methods: We screened a cohort of 134 unrelated families with split-hand/split-foot malformation (SHFM) with high resolution array CGH for CNVs with regulatory potential. Results: In three families with an autosomal dominant non-syndromic SHFM phenotype we detected microdeletions encompassing the exonic enhancer (eExons) 15 and 17 of DYNC1I1. In a fourth family, who had hearing loss in addition to SHFM, we found a larger deletion of 510 kb including the eExons of DYNC1I1 and, in addition, the human brain enhancer hs1642. Exons 15 and 17 of DYNC1I1 are known to act as tissue specific limb enhancers of DLX5/6, two genes that have been shown to be associated with SHFM in mice. In our cohort of 134 unrelated families with SHFM, deletions of the eExons of DYNC1I1 account for approximately 3% of the cases, while 17p13.3 duplications were identified in 13% of the families, 10q24 duplications in 12%, and TP63 mutations were detected in 4%. Conclusions: We reduce the minimal critical region for SHFM1 to 78 kb. Hearing loss, however, appears to be associated with deletions of a more telomeric region encompassing the brain enhancer element hs1642. Thus, SHFM1 as well as hearing loss at the same locus are caused by deletion of regulatory elements. Deletions of the exons with regulatory potential of DYNC1I1 are an example of the emerging role of exonic enhancer elements and their implications in congenital malformation syndromes. KW - SHFM KW - DLX5/6 KW - DYNC1I1 KW - regulatory mutations KW - eExons KW - tissue-specific enhancers KW - hand/foot malformation KW - II citrullinemia KW - limb development KW - human disease Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-115759 SN - 1750-1172 VL - 9 IS - 108 ER - TY - JOUR A1 - Liedtke, Daniel A1 - Hofmann, Christine A1 - Jakob, Franz A1 - Klopocki, Eva A1 - Graser, Stephanie T1 - Tissue-Nonspecific Alkaline Phosphatase—A Gatekeeper of Physiological Conditions in Health and a Modulator of Biological Environments in Disease JF - Biomolecules N2 - Tissue-nonspecific alkaline phosphatase (TNAP) is a ubiquitously expressed enzyme that is best known for its role during mineralization processes in bones and skeleton. The enzyme metabolizes phosphate compounds like inorganic pyrophosphate and pyridoxal-5′-phosphate to provide, among others, inorganic phosphate for the mineralization and transportable vitamin B6 molecules. Patients with inherited loss of function mutations in the ALPL gene and consequently altered TNAP activity are suffering from the rare metabolic disease hypophosphatasia (HPP). This systemic disease is mainly characterized by impaired bone and dental mineralization but may also be accompanied by neurological symptoms, like anxiety disorders, seizures, and depression. HPP characteristically affects all ages and shows a wide range of clinical symptoms and disease severity, which results in the classification into different clinical subtypes. This review describes the molecular function of TNAP during the mineralization of bones and teeth, further discusses the current knowledge on the enzyme’s role in the nervous system and in sensory perception. An additional focus is set on the molecular role of TNAP in health and on functional observations reported in common laboratory vertebrate disease models, like rodents and zebrafish. KW - TNAP KW - hypophosphatasia KW - HPP KW - zebrafish KW - mineralization KW - ALPL KW - craniosynostosis KW - teeth KW - nervous system Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-220096 SN - 2218-273X VL - 10 IS - 12 PB - MDPI ER - TY - JOUR A1 - Kolokotronis, Konstantinos A1 - Pluta, Natalie A1 - Klopocki, Eva A1 - Kunstmann, Erdmute A1 - Messroghli, Daniel A1 - Maack, Christoph A1 - Tejman-Yarden, Shai A1 - Arad, Michael A1 - Rost, Simone A1 - Gerull, Brenda T1 - New Insights on Genetic Diagnostics in Cardiomyopathy and Arrhythmia Patients Gained by Stepwise Exome Data Analysis JF - Journal of Clinical Medicine N2 - Inherited cardiomyopathies are characterized by clinical and genetic heterogeneity that challenge genetic diagnostics. In this study, we examined the diagnostic benefit of exome data compared to targeted gene panel analyses, and we propose new candidate genes. We performed exome sequencing in a cohort of 61 consecutive patients with a diagnosis of cardiomyopathy or primary arrhythmia, and we analyzed the data following a stepwise approach. Overall, in 64% of patients, a variant of interest (VOI) was detected. The detection rate in the main sub-cohort consisting of patients with dilated cardiomyopathy (DCM) was much higher than previously reported (25/36; 69%). The majority of VOIs were found in disease-specific panels, while a further analysis of an extended panel and exome data led to an additional diagnostic yield of 13% and 5%, respectively. Exome data analysis also detected variants in candidate genes whose functional profile suggested a probable pathogenetic role, the strongest candidate being a truncating variant in STK38. In conclusion, although the diagnostic yield of gene panels is acceptable for routine diagnostics, the genetic heterogeneity of cardiomyopathies and the presence of still-unknown causes favor exome sequencing, which enables the detection of interesting phenotype–genotype correlations, as well as the identification of novel candidate genes. KW - cardiomyopathy KW - cardiogenetics KW - whole exome sequencing KW - targeted gene panel KW - candidate genes Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-236094 VL - 9 IS - 7 ER - TY - JOUR A1 - Blümel, Rabea A1 - Zink, Miriam A1 - Klopocki, Eva A1 - Liedtke, Daniel T1 - On the traces of tcf12: Investigation of the gene expression pattern during development and cranial suture patterning in zebrafish (Danio rerio) JF - PLoS ONE N2 - The transcription factor 12 (tcf12) is a basic Helix-Loop-Helix protein (bHLH) of the E-protein family, proven to play an important role in developmental processes like neurogenesis, mesoderm formation, and cranial vault development. In humans, mutations in TCF12 lead to craniosynostosis, a congenital birth disorder characterized by the premature fusion of one or several of the cranial sutures. Current research has been primarily focused on functional studies of TCF12, hence the cellular expression profile of this gene during embryonic development and early stages of ossification remains poorly understood. Here we present the establishment and detailed analysis of two transgenic tcf12:EGFP fluorescent zebrafish (Danio rerio) reporter lines. Using these transgenic lines, we analyzed the general spatiotemporal expression pattern of tcf12 during different developmental stages and put emphasis on skeletal development and cranial suture patterning. We identified robust tcf12 promoter-driven EGFP expression in the central nervous system (CNS), the heart, the pronephros, and the somites of zebrafish embryos. Additionally, expression was observed inside the muscles and bones of the viscerocranium in juvenile and adult fish. During cranial vault development, the transgenic fish show a high amount of tcf12 expressing cells at the growth fronts of the ossifying frontal and parietal bones and inside the emerging cranial sutures. Subsequently, we tested the transcriptional activity of three evolutionary conserved non-coding elements (CNEs) located in the tcf12 locus by transient transgenic assays and compared their in vivo activity to the expression pattern determined in the transgenic tcf12:EGFP lines. We could validate two of them as tcf12 enhancer elements driving specific gene expression in the CNS during embryogenesis. Our newly established transgenic lines enhance the understanding of tcf12 gene regulation and open up the possibilities for further functional investigation of these novel tcf12 enhancer elements in zebrafish. KW - Zebrafish KW - Neurons KW - Skull KW - Enhancer elements KW - Hindbrain KW - Cranial sutures KW - Embryos KW - Somites Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-201428 VL - 14 IS - 6 ER - TY - JOUR A1 - Liedtke, Daniel A1 - Orth, Melanie A1 - Meissler, Michelle A1 - Geuer, Sinje A1 - Knaup, Sabine A1 - Köblitz, Isabell A1 - Klopocki, Eva T1 - ECM alterations in fndc3a (fibronectin domain containing protein 3A) deficient zebrafish cause temporal fin development and regeneration defects JF - Scientific Reports N2 - Fin development and regeneration are complex biological processes that are highly relevant in teleost fish. They share genetic factors, signaling pathways and cellular properties to coordinate formation of regularly shaped extremities. Especially correct tissue structure defined by extracellular matrix (ECM) formation is essential. Gene expression and protein localization studies demonstrated expression of fndc3a (fibronectin domain containing protein 3a) in both developing and regenerating caudal fins of zebrafish (Danio rerio). We established a hypomorphic fndc3a mutant line (fndc3a\(^{wue1/wue1}\)) via CRISPR/Cas9, exhibiting phenotypic malformations and changed gene expression patterns during early stages of median fin fold development. These developmental effects are mostly temporary, but result in a fraction of adults with permanent tail fin deformations. In addition, caudal fin regeneration in adult fndc3a\(^{wue1/wue1}\) mutants is hampered by interference with actinotrichia formation and epidermal cell organization. Investigation of the ECM implies that loss of epidermal tissue structure is a common cause for both of the observed defects. Our results thereby provide a molecular link between these developmental processes and foreshadow Fndc3a as a novel temporal regulator of epidermal cell properties during extremity development and regeneration in zebrafish. KW - Extracellular matrix KW - Limb development KW - Self-renewal Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-202141 VL - 9 ER - TY - JOUR A1 - Manukjan, Georgi A1 - Wiegering, Verena A1 - Reindl, Tobias A1 - Strauß, Gabriele A1 - Klopocki, Eva A1 - Schulze, Harald A1 - Andres, Oliver T1 - Novel variants in FERMT3 and RASGRP2 - Genetic linkage in Glanzmann-like bleeding disorders JF - Pediatric Blood & Cancer N2 - Defects of platelet intracellular signaling can result in severe platelet dysfunction. Several mutations in each of the linked genes FERMT3 and RASGRP2 on chromosome 11 causing a Glanzmann‐like bleeding phenotype have been identified so far. We report on novel variants in two unrelated pediatric patients with severe bleeding diathesis—one with leukocyte adhesion deficiency type III due to a homozygous frameshift in FERMT3 and the other with homozygous variants in both, FERMT3 and RASGRP2 . We focus on the challenging genetic and functional variant assessment and aim to accentuate the risk of obtaining misleading results due to the phenomenon of genetic linkage. KW - bleding disorders other than hemophilia KW - hematology KW - hemostasis and thrombosis KW - platelet disorders Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-208129 VL - 67 IS - 2 ER - TY - JOUR A1 - Vitale, Maria Rosaria A1 - Zöller, Johanna Eva Maria A1 - Jansch, Charline A1 - Janz, Anna A1 - Edenhofer, Frank A1 - Klopocki, Eva A1 - van den Hove, Daniel A1 - Vanmierlo, Tim A1 - Rivero, Olga A1 - Kasri, Nael Nadif A1 - Ziegler, Georg Christoph A1 - Lesch, Klaus-Peter T1 - Generation of induced pluripotent stem cell (iPSC) lines carrying a heterozygous (UKWMPi002-A-1) and null mutant knockout (UKWMPi002-A-2) of Cadherin 13 associated with neurodevelopmental disorders using CRISPR/Cas9 JF - Stem Cell Research N2 - Fibroblasts isolated from a skin biopsy of a healthy 46-year-old female were infected with Sendai virus containing the Yamanaka factors to produce transgene-free human induced pluripotent stem cells (iPSCs). CRISPR/Cas9 was used to generate isogenic cell lines with a gene dose-dependent deficiency of CDH13, a risk gene associated with neurodevelopmental and psychiatric disorders. Thereby, a heterozygous CDH13 knockout (CDH13\(^{+/-}\)) and a CDH13 null mutant (CDH13\(^{-/-}\)) iPSC line was obtained. All three lines showed expression of pluripotency-associated markers, the ability to differentiate into cells of the three germ layers in vitro, and a normal female karyotype. KW - CRISPR-Cas Systems KW - cadherins KW - female KW - heterozygote KW - humans KW - Induced Pluripotent Stem Cells KW - middle aged KW - neurodevelopmental disorders / genetics Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-260331 VL - 51 ER - TY - JOUR A1 - Ziegler, Georg C. A1 - Radtke, Franziska A1 - Vitale, Maria Rosaria A1 - Preuße, André A1 - Klopocki, Eva A1 - Herms, Stefan A1 - Lesch, Klaus-Peter T1 - Generation of multiple human iPSC lines from peripheral blood mononuclear cells of two SLC2A3 deletion and two SLC2A3 duplication carriers JF - Stem Cell Research N2 - Copy number variants of SLC2A3, which encodes the glucose transporter GLUT3, are associated with several neuropsychiatric and cardiac diseases. Here, we report the successful reprogramming of peripheral blood mononuclear cells from two SLC2A3 duplication and two SLC2A3 deletion carriers and subsequent generation of two transgene-free iPSC clones per donor by Sendai viral transduction. All eight clones represent bona fide hiPSCs with high expression of pluripotency genes, ability to differentiate into cells of all three germ layers and normal karyotype. The generated cell lines will be helpful to enlighten the role of glucometabolic alterations in pathophysiological processes shared across organ boundaries. KW - congenital heart-deffects KW - transporter gene SLC2A3 KW - copy-number variation Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-264696 VL - 56 ER - TY - JOUR A1 - Janz, Anna A1 - Zink, Miriam A1 - Cirnu, Alexandra A1 - Hartleb, Annika A1 - Albrecht, Christina A1 - Rost, Simone A1 - Klopocki, Eva A1 - Günther, Katharina A1 - Edenhofer, Frank A1 - Ergün, Süleyman A1 - Gerull, Brenda T1 - CRISPR/Cas9-edited PKP2 knock-out (JMUi001-A-2) and DSG2 knock-out (JMUi001-A-3) iPSC lines as an isogenic human model system for arrhythmogenic cardiomyopathy (ACM) JF - Stem Cell Research N2 - Arrhythmogenic cardiomyopathy (ACM) is characterized by fibro-fatty replacement of the myocardium, heart failure and life-threatening ventricular arrhythmias. Causal mutations were identified in genes encoding for proteins of the desmosomes, predominantly plakophilin-2 (PKP2) and desmoglein-2 (DSG2). We generated gene-edited knock-out iPSC lines for PKP2 (JMUi001-A-2) and DSG2 (JMUi001-A-3) using the CRISPR/Cas9 system in a healthy control iPSC background (JMUi001A). Stem cell-like morphology, robust expression of pluripotency markers, embryoid body formation and normal karyotypes confirmed the generation of high quality iPSCs to provide a novel isogenic human in vitro model system mimicking ACM when differentiated into cardiomyocytes. KW - mutations Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-259846 VL - 53 ER - TY - JOUR A1 - Ohlebusch, Barbara A1 - Borst, Angela A1 - Frankenbach, Tina A1 - Klopocki, Eva A1 - Jakob, Franz A1 - Liedtke, Daniel A1 - Graser, Stephanie T1 - Investigation of alpl expression and Tnap-activity in zebrafish implies conserved functions during skeletal and neuronal development JF - Scientific Reports N2 - Hypophosphatasia (HPP) is a rare genetic disease with diverse symptoms and a heterogeneous severity of onset with underlying mutations in the ALPL gene encoding the ectoenzyme Tissue-nonspecific alkaline phosphatase (TNAP). Considering the establishment of zebrafish (Danio rerio) as a new model organism for HPP, the aim of the study was the spatial and temporal analysis of alpl expression in embryos and adult brains. Additionally, we determined functional consequences of Tnap inhibition on neural and skeletal development in zebrafish. We show that expression of alpl is present during embryonic stages and in adult neuronal tissues. Analyses of enzyme function reveal zones of pronounced Tnap-activity within the telencephalon and the mesencephalon. Treatment of zebrafish embryos with chemical Tnap inhibitors followed by axonal and cartilage/mineralized tissue staining imply functional consequences of Tnap deficiency on neuronal and skeletal development. Based on the results from neuronal and skeletal tissue analyses, which demonstrate an evolutionary conserved role of this enzyme, we consider zebrafish as a promising species for modeling HPP in order to discover new potential therapy strategies in the long-term. KW - nonspecific alkaline-phosphae KW - in situ hybridization KW - hypophosphatasia KW - promotes KW - model KW - neurotransmission KW - differentiation KW - mineraliztion KW - metabolism KW - vertebrate Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-230024 VL - 10 ER -