Molecular Structure and Function of Chemical Synapses in the Retina
A main issue in the neurosciences concerns the mechanisms underlying the exchange of information between neurons. Communication among neurons is achieved via defined contacts, the synapses. Chemical synapses belong to the most important and interesting structures in the nervous system. A plethora of biochemical and biophysical reactions, responsible for information processing, takes place in the small area of chemical synapses. Synaptopathies = malfunctioning synapses are a reason for many neurological disorders and neurodegenerative diseases.
Research in our laboratory focuses on molecules and mechanisms that play a role in the development and the structural and functional organization of chemical synapses in the Central Nervous System (CNS). We want to understand how synapses form during synaptogenesis, how they mature, turnover and plastically change, how they release neurotransmitter presynaptically and bind neurotransmitter and process the signal postsynaptically. Molecules of interest include cytomatrix proteins at the active zone, proteins of the neurotransmitter exocytosis machinery, neurotransmitter receptors and their interacting molecules, clustering molecules, and various kinds of membrane channels.
With our studies we hope to contribute to a better understanding of the structure and function of chemical synapses in health and disease.
The mammalian retina – a model system in the neurosciences
The mammalian retina is the main experimental system used in our studies. The retina is part of the CNS and the clear structure, the highly detailed anatomy, the easy accessibility for experimental perturbations, and the presence of morphologically and functionally distinct types of chemical synapses – conventional and ribbon synapses – make the retina one of the most important model systems in the neurosciences. The retinal photoreceptor ribbon synapses, for example, are structurally and functionally specialized for the continuous release of neurotransmitter, which makes them the most complex type of chemical synapse found in the CNS.
In our experimental approach, we combine neuroanatomical, immunocytochemical, biochemical, molecular, cell biological and physiological methods to investigate the retinae of wildtype, mutant, and transgenic mice.
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