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Primary dendrites of mitral cells synapse unto neighboring glomeruli independent of their odorant receptor identity.

ABSTRACT: In the mouse olfactory bulb, neural map topography is largely established by axon-axon interactions of olfactory sensory neurons (OSNs). However, to make the map functional, the OSNs must make proper connections to second-order neurons, the mitral cells. How do the mitral-cell dendrites find their partner glomeruli for synapse formation with OSN axons? Here, we analyze dendrite connections of mitral cells in various mutant mice in which glomerular formation is perturbed. Our present results support the proximity model, whereby mitral cells tend to connect primary dendrites to the nearest neighboring glomeruli regardless of their odorant receptor identities. The physical location of glomeruli rather than the odorant-receptor specificity appears to play a key role in matching mitral cells with their partner OSN axons.

SUBMITTER: Nishizumi H

PROVIDER: S-EPMC6325062 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Primary dendrites of mitral cells synapse unto neighboring glomeruli independent of their odorant receptor identity.

Nishizumi Hirofumi H Miyashita Akihiro A Inoue Nobuko N Inokuchi Kasumi K Aoki Mari M Sakano Hitoshi H

Communications biology 20190108

In the mouse olfactory bulb, neural map topography is largely established by axon-axon interactions of olfactory sensory neurons (OSNs). However, to make the map functional, the OSNs must make proper connections to second-order neurons, the mitral cells. How do the mitral-cell dendrites find their partner glomeruli for synapse formation with OSN axons? Here, we analyze dendrite connections of mitral cells in various mutant mice in which glomerular formation is perturbed. Our present results supp ...[more]

PMID: 30652126

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