Advisor: David Lin Start Date:
Fall 2004
The ability to detect and discriminate chemicals in the environment is utilized by organisms ranging from bacteria to mammals. As much as 4% of the genome of most higher eukaryotes is devoted to encoding olfactory protein. In mammals, discrimination of different odors is carried out by the convergence of like olfactory receptor neurons at specific glomeruli within the olfactory bulb. In our lab, we hypothesize that the olfactory bulb must emit cues in order to guide the olfactory sensory neurons to the correct glomeruli. In my research, I intend to prove this hypothesis by isolating these cues and showing that the olfactory sensory neurons cannot grow to the correct glomeruli without them.
Research Flow Chart
Identification of olfactory bulb guidance cues: We predict that olfactory bulb guidance cues must be spatially and temporally expressed in the olfactory bulb. To determine which genes are differentially expressed, I am using microarray technology to study different regions and layers of the olfactory bulb at different developmental stages. Using laser microdissection, I isolate different layers of tissue from the anterior, posterior, medial, lateral, dorsal and ventral regions of the olfactory bulb. Microarray data is analyzed and reconstructed into a three dimensional topographical map of the olfactory bulb. From this map spatially expressed genes are identified.
Functional analysis of olfactory cues: We expect that the disruption of the identified olfactory bulb cues will result in the abnormal convergence of olfactory sensory neurons. In order to prove that the genes identified by microarray analysis are indeed olfactory bulb cues, I plan to create mutant mice deficient in the olfactory bulb cue genes. In this way I plan to unravel the mechanisms by which olfactory bulb cues guide olfactory sensory neurons to specific glomeruli.
