Structural and Functional Analysis of the Neuronal Circuits Connecting Sensory Processing and Motor Control
You will identify and analyze the neurons in the pathways that connect sensory centres and motor control centres. No one has analyzed these neurons systematically before; your finding will therefore be highly unique. To identify such neurons, you combine two types of expression driver strains and visualize specific types of neurons. Many combinations should be tested to identify as many neurons as possible in a certain brain region. You will also examine the electron microscopy "connectome" data.
By comparing the structure of the neurons you identified, you will then classify these neurons and make a neuronal circuit diagram. To understand the functions of these neurons, you will express calcium indicator proteins in specific cells and analyze their activities during walking behaviour. To do this, you fix the head of a fly under a small metal plate, make a very small hole on the head, place the fly on a trackball, and examine neuronal activities deep in the brain with a two-photon microscope. Different neurons will show different activity patterns.
By integrating the information about the morphology and activity of various neurons, you will understand how information is conveyed from sensory centres to motor centres.
Methodology & Research Model
Fruit fly (Drosophila melanogaster)
Molecular genetics - handling of transgenic fly strains, genetic cross
Sample preparation and imaging - dissection of the brains, antibody labeling, confocal laser scanning microscopy
Computer-assisted image analysis - examination of image database, 3D comparison of image data, 3D volume reconstruction, clustering
Neuron activity imaging - expression of calcium indicator proteins, live imaging with a two-photon microscope, video analysis
Requirements for Application
Applicants need to hold or be about to complete a M.Sc. degree or equivalent in neurosciences, biological sciences or life sciences. Very good background knowledge in neurobiology, neuroscience and experimental design acquired during master studies is required.
Tsubouchi A, Yano T, Yokoyama TK, Murtin C, Otsuna H, Ito K. Topological and modality-specific representation of somatosensory information in the fly brain. Science, 358, 615-623, 2017
Ito M, Masuda N, Shinomiya K, Endo K, Ito K. Systematic analysis of neural projections reveals clonal composition of the Drosophila brain. Curr Biol, 23, 644–655, 2013.