BIO

My Story

I was trained as a developmental neurobiologist at the University of Jena, Germany. I started to study embryonic development of mice in the laboratory of Prof. Dr. Jurgen Bolz at the University of Jena, Germany. At that time, the laboratory was interested in the guidance mechanisms of interneurons, migrating from their place of cell division in the basal forebrain all the way to the cortex. We found that several guidance molecules from the ephrin/Eph receptor tyrosine kinase family were specifically expressed in the basal forebrain. I participated in establishing new in vitro assays in the laboratory that helped to gain insight into exact migration processes of neurons and developed in utero electroporation which was useful to explore the functional significance of our findings in vivo.

In the beginning of my PhD, we discovered that a gene, called “Disrupted in Schizophrenia 1” (DISC1), is playing a crucial role in the migration of other neuron types and is also expressed in migrating interneurons. 

During the study of interneuron migration I always asked myself what is next; what are the cells doing afterwards and what regulates their further development? I joined the laboratory of Hiroki Taniguchi, PhD at the Max Planck Florida Institute for Neuroscience to study the postnatal development of cortical interneurons. Specifically, I was interested in the network integration of cortical Chandelier cells (ChCs) or axo-axonic cells. These GABA-ergic interneurons precisely innervate the axon initial segment (AIS) of only pyramidal neurons in the cortex. The AIS is the output structure of neurons, the part where the action potential is generated. One ChC is therefore thought to have decisive output control over a large network of cortical pyramidal cells by innervating between 150 and 250 pyramidal neurons. I asked how these ChCs find not only their specific target pyramidal neurons but their specific sub-compartment target, the AIS, to build their synapses with. Using state of the art light microscopy and electron I discovered that the axon of ChCs contain non-synaptic varicosities whose function were entirely enigmatic. These structures seem to also be developmentally regulated as they are expanded during the second postnatal week and reduced during the third. I hypothesized that non-synaptic varicosities could serve as origins of axonal branches during development, which would explain the concomitant expansion and refinement. We could later confirm this idea by combining 2-photon microscopy and post-hoc analysis of the axonal structures. 

In summary, my undergraduate and postdoctoral training as a developmental neurobiologist enabled me to study multiple aspects of interneuron development from embryonic to adult stages. Descending into the particularities of neuronal development, I contributed to building new knowledge about how genes work together with the environment to shape proper brain structure, which we know now is critical for proper brain function. I aim to continue to dissect and investigate the mechanisms of interneurons development in the future .