Strength in diversity: functional diversity among olfactory neurons of the same type
Most animals depend upon olfaction to find food, mates, and to avoid predators. An animal’s olfactory circuit helps it sense its olfactory environment and generate critical behavioral responses. The general architecture of the olfactory circuit, which is conserved across species, is made up of a few different neuronal types including first-order receptor neurons, second- and third-order neurons, and local interneurons. Each neuronal type differs in their morphology, physiology, and neurochemistry. However, several recent studies have suggested that there is intrinsic diversity even among neurons of the same type and that this diversity is important for neural function. In this review, we first examine instances of intrinsic diversity observed among individual types of olfactory neurons. Next, we review potential genetic and experience-based plasticity mechanisms that underlie this diversity. Finally, we consider the implications of intrinsic neuronal diversity for circuit function. Overall, we hope to highlight the importance of intrinsic diversity as a previously underestimated property of circuit function.
KeywordsOlfaction Neuronal diversity Olfactory receptor neurons Interneuron Mitral cell Projection neuron
The authors are supported by a grant from the NIGMS of the National Institute of Health under grant number P20 GM103650 and by startup funds from the University of Nevada, Reno awarded to DM.
Compliance with ethical standards
Conflict of interest
The authors declare no competing financial interests.
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