The role of cellular excitability and neurotransmission in functional circuit assembly in the mammalian retina

• Applicant: Dr. Daniel Kerschensteiner
• Subject Area: Ophthalmology
• Term: from 2007 to 2009
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 42553631

Information in all parts of the nervous system is processed in networks of intricately connected cells. Studying the mechanisms that guide the formation and refinement of precise connections during development therefore is fundamental to understanding nervous system function. The development of the mammalian retina has been studied for over a century, and key principles of its functional organization have been identified and correlated to structural features making this an ideal system for analyzing mechanisms that shape circuit assembly. Toward this end, I recently generated three transgenic mouse lines which interfere with the activity of and/or transmitter release from depolarizing bipolar cells or in which those cells are removed from the developing retina. Using these mice, I propose to study how cellular excitability, the ability to excite postsynaptic targets, and interactions between neighboring cells influence the axonal targeting of bipolar interneurons and regulate the dendritic territories they come to occupy. In addition, I will analyze how reduced or removed bipolar cell input regulates the dendritic remodeling and allocation of postsynaptic resources in retinal ganglion cells which are the targets of bipolar cells in the inner retina. Finally, visual responses of retinal ganglion cells in these retinas will be examined to elucidate how changes in circuit assembly affect sensory function.

• DFG Programme: Research Fellowships
• International Connection: USA
• Host: Professorin Rachel Wong