TY - THES A1 - Forero Echeverry, Andrea Marcela T1 - Impact of Cadherin-13 deficiency on the brain serotonin system using mouse models and human iPSC-derived neurons T1 - Einfluss einer Cadherin-13 Defizienz auf das Serotonin-System des Gehirns unter Verwendung von Mausmodellen und humanen iPSC-abgeleiteten Neuronen N2 - Serotonin (5-hydroxytryptamine, 5-HT) is a neurotransmitter involved in early developmental processes such as cell proliferation, migration, and differentiation. Recent research in humans showed that the brain 5-HT system and CDH13 are interlinked in the genetics of neurodevelopmental disorders including attention- deficit/hyperactivity disorder and autism spectrum disorder (Lesch et al., 2008; Neale et al., 2008; Neale, Medland, Ripke, Anney, et al., 2010; Neale, Medland, Ripke, Asherson, et al., 2010; Sanders et al., 2011; Sanders et al., 2015; Zhou et al., 2008). This study introduces Cadherin-13 (CDH13), a cell adhesion protein, as a contributor to the development and function of the 5-HT system. Our experiments show that the absence of CDH13 increases the density of 5-HT neurons in the developing dorsal raphe (DR) and increases the 5-HT innervation of the prefrontal cortex in mouse embryonic stages. CDH13 is also observed in radial glial cells, an important progenitor cell type linked to neuronal migration. A three-dimensional reconstruction carried out with super-resolution microscopy, identifies 5-HT neurons intertwined with radial glial cells, and CDH13 clusters at contact points between these cells. This indicates a potential contribution of CDH13 to the migration of DR 5-HT neurons. As CDH13 is strongly expressed in 5-HT neurons, we asked whether the selective deletion of CDH13 from these cells is sufficient to generate the alterations observed in the Cdh13 constitutive knockout mouse line. In 5-HT conditional Cdh13 knockout mice (Cdh13 cKO) an increase in DR 5-HT neurons in the embryonic and adult brains is observed, as well as 5-HT hyperinnervation of cortical regions. Therefore, illustrating that the lack of CDH13 from 5-HT neurons alone impacts DR formation and serotonergic innervation. Behavioral testing conducted on Cdh13 cKO mice showed delayed learning in visuospatial learning and memory processing, as well as, changes in sociability parameters. To find out how CDH13 localizes in human 5-HT neurons, CDH13 was visualized in neurons that derived from human induced pluripotent stem cells (iPSC). Super-resolution microscopy confirmed CDH13 expression in a subgroup of induced human neurons positive for typical hallmarks of 5-HT neurons, such as expression of Tph2, the neuron-specific tryptophan hydroxylase, and synaptic structures. In summary, the work included in this thesis presents a detailed analysis of CDH13 expression and localization in the 5-HT system and shows that deletion of CDH13 from 5-HT neurons affects specific higher-order functions of the brain. N2 - Serotonin (5-Hydroxytryptamin, 5-HT) ist ein Neurotransmitter, der in frühe Entwicklungsprozesse involviert ist, wie beispielsweise Zellproliferation, Migration und Differenzierung. Aktuelle Forschungsergebnisse im Menschen zeigten eine Verbindung zwischen dem 5-HT System des Gehirns und CDH13 in der Genetik neurologischer Entwicklungsstörungen, wie die Aufmerksamkeitsdefizit-/Hyperaktivitätsstörung und die Autismus-Spektrum-Störung (Lesch et al., 2008; Neale, Medland, Ripke, Anney, et al., 2010; Neale, Medland, Ripke, Asherson, et al., 2010; Sanders et al., 2011; Sanders et al., 2015; Zhou et al., 2008). Diese Studie präsentiert Cadherin-13 (CDH13), ein Zelladhäsionsprotein, als einen Gegenspieler in der Entwicklung und Funktion des 5-HT Systems. Unsere Experimente zeigen, dass die Abwesenheit von CDH13 die Dichte der 5-HT Neuronen in dem sich entwickelnden dorsalen Raphe (DR) sowie die 5-HT Innervation des Präfrontalen Kortex in den embryonalen Stadien der Maus steigert. CDH13 wird auch in Radialen Gliazellen beobachtet, ein wichtiger Vorläuferzelltyp, der mit neuronaler Migration in Verbindung gebracht wurde. Eine 3-dimensionale Rekonstruktion, durchgeführt mit Superresolutions-Mikroskopie, identifiziert 5-HT Neuronen verflochten mit Radialen Gliazellen und CDH13 in den Kontaktpunkten zwischen diesen Zellen. Dies verdeutlicht eine potenzielle Rolle von CDH13 bei der Migration der DR 5-HT Neuronen. Da CDH13 eine starke Expression in den 5-HT Neuronen aufweist, fragten wir uns, ob die selektive Deletion von CDH13 in den Zellen ausreichend sei, um die in der konstitutiven Cdh13 Knockout-Mauslinie beobachteten Veränderung zu erzeugen. In 5-HT konditionalen Cdh13 Knockout-Mäusen (Cdh13 cKO) wurde eine Erhöhung der Anzahl der DR 5-HT Neuronen im embryonalen und adulten Gehirn sowie eine 5-HT Überinnervation der kortikalen Regionen beobachtet. Dies veranschaulicht, dass bereits ein Mangel an CDH13 in 5-HT Neuronen die DR-Ausbildung und serotonerge Innervation beeinflusst. Verhaltensversuche, die an Cdh13 cKO-Mäusen durchgeführt wurden, zeigten verspätetes Lernen im visuell-räumlichen Spektrum und der Gedächtnisverarbeitung sowie Veränderungen der Soziabilitätsparameter. Um herauszufinden, wie CDH13 in humanen 5-HT Neuronen lokalisiert ist, wurde CDH13 in aus humanen pluripotenten Stammzellen (iPSC) erzeugten Neuronen visualisiert. Superresolutions-Mikroskopie bestätigte eine CDH13 Expression in einer Untergruppe induzierter humaner Neuronen, die typische Merkmale von 5-HT Neuronen, wie etwa die Expression der Neuronen-spezifischen Tryptophan-Hydroxylase Tph2 und synaptische Strukturen, aufweisen. Zusammengefasst präsentiert diese Doktorarbeit eine detaillierte Analyse der CDH13 Expression und Lokalisation im 5-HT System und zeigt, dass eine Deletion von CDH13 in 5-HT Neuronen spezifische höhergradige Funktionen des Gehirns beeinflusst. KW - neurodevelopment KW - cadherin-13 KW - serotonin Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-216592 ER - TY - JOUR A1 - Jansch, Charline A1 - Ziegler, Georg C. A1 - Forero, Andrea A1 - Gredy, Sina A1 - Wäldchen, Sina A1 - Vitale, Maria Rosaria A1 - Svirin, Evgeniy A1 - Zöller, Johanna E. M. A1 - Waider, Jonas A1 - Günther, Katharina A1 - Edenhofer, Frank A1 - Sauer, Markus A1 - Wischmeyer, Erhard A1 - Lesch, Klaus-Peter T1 - Serotonin-specific neurons differentiated from human iPSCs form distinct subtypes with synaptic protein assembly JF - Journal of Neural Transmission N2 - Human induced pluripotent stem cells (hiPSCs) have revolutionized the generation of experimental disease models, but the development of protocols for the differentiation of functionally active neuronal subtypes with defined specification is still in its infancy. While dysfunction of the brain serotonin (5-HT) system has been implicated in the etiology of various neuropsychiatric disorders, investigation of functional human 5-HT specific neurons in vitro has been restricted by technical limitations. We describe an efficient generation of functionally active neurons from hiPSCs displaying 5-HT specification by modification of a previously reported protocol. Furthermore, 5-HT specific neurons were characterized using high-end fluorescence imaging including super-resolution microscopy in combination with electrophysiological techniques. Differentiated hiPSCs synthesize 5-HT, express specific markers, such as tryptophan hydroxylase 2 and 5-HT transporter, and exhibit an electrophysiological signature characteristic of serotonergic neurons, with spontaneous rhythmic activities, broad action potentials and large afterhyperpolarization potentials. 5-HT specific neurons form synapses reflected by the expression of pre- and postsynaptic proteins, such as Bassoon and Homer. The distribution pattern of Bassoon, a marker of the active zone along the soma and extensions of neurons, indicates functionality via volume transmission. Among the high percentage of 5-HT specific neurons (~ 42%), a subpopulation of CDH13 + cells presumably designates dorsal raphe neurons. hiPSC-derived 5-HT specific neuronal cell cultures reflect the heterogeneous nature of dorsal and median raphe nuclei and may facilitate examining the association of serotonergic neuron subpopulations with neuropsychiatric disorders. KW - neuropsychiatric disorders KW - human induced pluripotent stem cell (hiPSC) KW - serotonin-specific neurons KW - median and dorsal raphe KW - synapse formation KW - Cadherin-13 (CDH13) Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-268519 SN - 1435-1463 VL - 128 IS - 2 ER - TY - JOUR A1 - Jansch, Charline A1 - Günther, Katharina A1 - Waider, Jonas A1 - Ziegler, Georg C. A1 - Forero, Andrea A1 - Kollert, Sina A1 - Svirin, Evgeniy A1 - Pühringer, Dirk A1 - Kwok, Chee Keong A1 - Ullmann, Reinhard A1 - Maierhofer, Anna A1 - Flunkert, Julia A1 - Haaf, Thomas A1 - Edenhofer, Frank A1 - Lesch, Klaus-Peter T1 - Generation of a human induced pluripotent stem cell (iPSC) line from a 51-year-old female with attention-deficit/hyperactivity disorder (ADHD) carrying a duplication of SLC2A3 JF - Stem Cell Research N2 - Fibroblasts were isolated from a skin biopsy of a clinically diagnosed 51-year-old female attention-deficit/hyperactivity disorder (ADHD) patient carrying a duplication of SLC2A3, a gene encoding neuronal glucose transporter-3 (GLUT3). Patient fibroblasts were infected with Sendai virus, a single-stranded RNA virus, to generate transgene-free human induced pluripotent stem cells (iPSCs). SLC2A3-D2-iPSCs showed expression of pluripotency-associated markers, were able to differentiate into cells of the three germ layers in vitro and had a normal female karyotype. This in vitro cellular model can be used to study the role of risk genes in the pathogenesis of ADHD, in a patient-specific manner. KW - ADHD KW - SLC2A3 KW - induced pluripotent stem cells Y1 - 2018 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-176654 VL - 28 ER -