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  - Tretter, Verena
A1  - Mukherjee, Jayanta
A1  - Maric, Hans-Michael
A1  - Schindelin, Hermann
A1  - Sieghart, Werner
A1  - Moss, Stephen J.
T1  - Gephyrin, the enigmatic organizer at GABAergic synapses
JF  - Frontiers in Cellular Neuroscience
N2  - GABA(A) receptors are clustered at synaptic sites to achieve a high density of postsynaptic receptors opposite the input axonal terminals. This allows for an efficient propagation of GABA mediated signals, which mostly result in neuronal inhibition. A key organizer for inhibitory synaptic receptors is the 93 kDa protein gephyrin that forms oligomeric superstructures beneath the synaptic area. Gephyrin has long been known to be directly associated with glycine receptor beta subunits that mediate synaptic inhibition in the spinal cord. Recently, synaptic GABA(A) receptors have also been shown to directly interact with gephyrin and interaction sites have been identified and mapped within the intracellular loops of the GABA(A) receptor alpha 1, alpha 2, and alpha 3 subunits. Gephyrin-binding to GABA(A) receptors seems to be at least one order of magnitude weaker than to glycine receptors (GlyRs) and most probably is regulated by phosphorylation. Gephyrin not only has a structural function at synaptic sites, but also plays a crucial role in synaptic dynamics and is a platform for multiple protein-protein interactions, bringing receptors, cytoskeletal proteins and downstream signaling proteins into close spatial proximity.
KW  - scaffolding protein gephyryrin
KW  - containing GABA(A) receptors
KW  - GABA(A) receptors
KW  - inhibitory synapse
KW  - gamma-aminobutyric-acid
KW  - receptor-beta subunits
KW  - molybdenum cofactor biosynthesis
KW  - temporal-lobe epilepsy
KW  - cultured hippocampal-neurons
KW  - exchange factor collybistin
KW  - rat spinal-cord
KW  - glycine
KW  - gephyrin
KW  - receptor clustering
KW  - synapse formation
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-133356
VL  - 6
IS  - 23
ER  -