Dissecting local circuits: parvalbumin interneurons underlie broad feedback control of olfactory bulb output.
In the mouse olfactory bulb, information from sensory neurons is extensively processed by local interneurons before being transmitted to the olfactory cortex by mitral and tufted (M/T) cells. The precise function of these local networks remains elusive because of the vast heterogeneity of interneurons, their diverse physiological properties, and their complex synaptic connectivity. Here we identified the parvalbumin interneurons (PVNs) as a prominent component of the M/T presynaptic landscape by using an improved rabies-based transsynaptic tracing method for local circuits. In vivo two-photon-targeted patch recording revealed that PVNs have exceptionally broad olfactory receptive fields and exhibit largely excitatory and persistent odor responses. Transsynaptic tracing indicated that PVNs receive direct input from widely distributed M/T cells. Both the anatomical and functional extent of this M/T→PVN→M/T circuit contrasts with the narrowly confined M/T→granule cell→M/T circuit, suggesting that olfactory information is processed by multiple local circuits operating at distinct spatial scales.
Department of Biology, Howard Hughes Medical Institute, Stanford University, Stanford, CA 94305, USA.
Kazunari
K
Miyamichi
Yael
Y
Shlomai-Fuchs
Marvin
M
Shu
Brandon C
BC
Weissbourd
Liqun
L
Luo
Adi
A
Mizrahi
D000200:Action Potentials / Q000235:genetics / Q000502:physiology; D000818:Animals; D000831:Animals, Newborn; D000070585:Cadherin Related Proteins; D015820:Cadherins / Q000235:genetics; D025461:Feedback, Physiological / Q000502:physiology*; D005968:Glutamate Decarboxylase / Q000235:genetics; D066298:In Vitro Techniques; D007395:Interneurons / Q000378:metabolism*; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008822:Mice, Transgenic; D009415:Nerve Net / Q000502:physiology*; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism; D009434:Neural Pathways / Q000502:physiology*; D009812:Odorants; D009830:Olfactory Bulb / Q000166:cytology*; D010320:Parvalbumins / Q000235:genetics / Q000378:metabolism*; D018408:Patch-Clamp Techniques; D022661:RNA, Untranslated / Q000235:genetics / Q000378:metabolism
C442481:CDHR1 protein, human; D000070585:Cadherin Related Proteins; D015820:Cadherins; C110853:Gt(ROSA)26Sor non-coding RNA, mouse; D008164:Luminescent Proteins; D009419:Nerve Tissue Proteins; D010320:Parvalbumins; D022661:RNA, Untranslated; D005968:Glutamate Decarboxylase; C401141:glutamate decarboxylase 2