Olfactory system

Article
20 December 2023 | Open Access

RNA-mediated symmetry breaking enables singular olfactory receptor choice

Messenger RNAs transcribed from olfactory-receptor genes may have non-coding functions that include recruitment of transcriptional enhancers and inhibition of potentially thousands of competing alleles to ensure stable transcription of a single allele.

Ariel D. Pourmorady
, Elizaveta V. Bashkirova
& Stavros Lomvardas

Article | 15 March 2023

Structural basis of odorant recognition by a human odorant receptor

Through the use of cryo-electron microscopy and molecular dynamics stimulations, mechanistic insight into the binding of an odorant to the human odorant receptor OR51E2 is provided.

Christian B. Billesbølle
, Claire A. de March
& Aashish Manglik

Article | 09 November 2022

Odour motion sensing enhances navigation of complex plumes

Odour motion contains valuable directional information that is absent from the airflow alone, and Drosophila use this directional information to shape their navigational decisions.

Nirag Kadakia
, Mahmut Demir
& Thierry Emonet

Article | 11 May 2022

Olfactory sensory experience regulates gliomagenesis via neuronal IGF1

A mouse model of gliomagenesis reveals that olfaction can directly regulate the genesis of gliomas, showing that sensory experience and gliomagenesis are linked and providing insight into the neural circuitry involved.

Pengxiang Chen
, Wei Wang
& Chong Liu

Article | 04 May 2022

Mosquito brains encode unique features of human odour to drive host seeking

Select chemical compounds enriched in human odour activate an olfactory glomerulus in the brain of Aedes aegypti mosquitoes, which strengthens host-seeking behaviour and helps explain their strong preference for biting humans.

Zhilei Zhao
, Jessica L. Zung
& Carolyn S. McBride

Article
07 March 2022 | Open Access

SARS-CoV-2 is associated with changes in brain structure in UK Biobank

After infection with SARS-CoV-2, individuals show a greater reduction in grey matter thickness and tissue contrast in the orbitofrontal cortex and parahippocampal gyrus; greater changes in markers of tissue damage in regions that are functionally connected to the primary olfactory cortex; and a greater reduction in global brain size.

Gwenaëlle Douaud
, Soojin Lee
& Stephen M. Smith

Article | 22 December 2021

Spatial maps in piriform cortex during olfactory navigation

Studies using neural ensemble recordings in rats show that cells in the piriform cortex carry a spatial representation of the environment and link locations to olfactory sensory inputs.

Cindy Poo
, Gautam Agarwal
& Zachary F. Mainen

Article | 09 June 2021

Representational drift in primary olfactory cortex

All odours elicit a unique pattern of neuronal activity in primary olfactory cortex but these patterns drift over time, posing a problem for the perceptual constancy of odours.

Carl E. Schoonover
, Sarah N. Ohashi
& Andrew J. P. Fink

Article | 05 May 2021

Fast odour dynamics are encoded in the olfactory system and guide behaviour

Fast temporal dynamics of the olfactory environment can be perceived by mice and used to perform scene segmentation.

Tobias Ackels
, Andrew Erskine
& Andreas T. Schaefer

Article | 31 March 2021

An amygdala circuit that suppresses social engagement

A circuit in the amygdala uses thyrotropin-releasing hormone to suppress male mating when a female mouse is unhealthy.

Jeong-Tae Kwon
, Changhyeon Ryu
& Gloria B. Choi

Article | 11 November 2020

A measure of smell enables the creation of olfactory metamers

By collecting nearly 50,000 perceptual estimates of smell, a reliable physicochemical measure that links odorant structure to odorant perception at a resolution that enables the creation of olfactory metamers was derived.

Aharon Ravia
, Kobi Snitz
& Noam Sobel

Article | 01 July 2020

Structure and flexibility in cortical representations of odour space

Both piriform cortex and its sensory inputs from the olfactory bulb represent chemical odour relationships, but cortex reshapes relational information inherited from the sensory periphery to enhance odour generalization and to reflect experience.

Stan L. Pashkovski
, Giuliano Iurilli
& Sandeep Robert Datta

Article | 04 March 2020

Olfactory receptor and circuit evolution promote host specialization

A neurogenetic model, Drosophila sechellia—a relative of Drosophila melanogaster that has developed an extreme specialization for a single host plant—sheds light on the evolution of interspecific differences in behaviour.

Thomas O. Auer
, Mohammed A. Khallaf
& Richard Benton

Article | 09 January 2019

LHX2- and LDB1-mediated trans interactions regulate olfactory receptor choice

Specific interchromosomal contacts in olfactory sensory neurons form a super-enhancer that controls the expression of a single olfactory receptor in each neuron.

Kevin Monahan
, Adan Horta
& Stavros Lomvardas

Letter | 21 November 2018

Distinct activity-gated pathways mediate attraction and aversion to CO₂ in Drosophila

Drosophila melanogaster are attracted to CO₂ when in an active, foraging state but experience aversion to CO₂ at low-activity levels, whereas they are attracted to ethanol in all behavioural states.

Floris van Breugel
, Ainul Huda
& Michael H. Dickinson

Letter | 26 September 2018

A natural variant and engineered mutation in a GPCR promote DEET resistance in C. elegans

DEET interferes selectively with chemotaxis of Caenorhabditis elegans nematodes, and mutations in the str-217 gene or silencing of the pair of chemosensory neurons that express it makes worms DEET-resistant.

Emily J. Dennis
, May Dobosiewicz
& Leslie B. Vosshall

Article | 15 August 2018

Cryo-EM structure of the insect olfactory receptor Orco

A cryo-electron microscopy structure of the insect Orco subunit, which forms ion channels with diverse olfactory receptors, reveals a tetrameric cation channel and sheds light on insect olfaction.

Joel A. Butterwick
, Josefina del Mármol
& Vanessa Ruta

Letter | 24 October 2016

Olfactory receptor pseudo-pseudogenes

Drosophila sechellia, a species closely related to the model species Drosophila melanogaster, bypasses a premature stop codon in neuronal cells to express a functional olfactory receptor protein from an assumed pseudogene template.

Lucia L. Prieto-Godino
, Raphael Rytz
& Richard Benton

Brief Communications Arising | 22 June 2016

Ir40a neurons are not DEET detectors

Ana F. Silbering
, Rati Bell
& Richard Benton

Letter | 21 March 2016

A specific area of olfactory cortex involved in stress hormone responses to predator odours

Exposure to predator scents triggers an instinctive fear response in mice, including a surge in blood levels of stress hormones; here, the amygdalo-piriform transition area is identified as provoking these hormonal responses.

Kunio Kondoh
, Zhonghua Lu
& Linda B. Buck

Letter | 30 September 2015

Plasticity-driven individualization of olfactory coding in mushroom body output neurons

Neuronal representations of sensory stimuli tend to become sparse and decorrelated, with different odours giving rise to fewer neuronal spikes in rare neurons, as signal processing moves up to higher brain layers; here comprehensive recording from the Drosophila olfactory processing centre finds instead some highly correlated tuning curves that vary flexibly from animal to animal.

Toshihide Hige
, Yoshinori Aso
& Glenn C. Turner

Article | 12 November 2014

Evolution of mosquito preference for humans linked to an odorant receptor

The mosquito Aedes aegypti includes two subspecies, one of which shows a preference for biting humans, whereas the other prefers to bite non-human animals; genetic analysis reveals that changes in the mosquito odorant receptor Or4 contribute to the behavioural difference—in human-preferring mosquitoes, Or4 is more highly expressed and more sensitive to sulcatone, a compound present at high levels in human odour.

Carolyn S. McBride
, Felix Baier
& Leslie B. Vosshall

Letter | 05 November 2014

The participation of cortical amygdala in innate, odour-driven behaviour

The cortical amygdala is necessary and sufficient for processing odours that evoke aversive and attractive responses without learning.

Cory M. Root
, Christine A. Denny
& Richard Axel

Article | 14 May 2014

Galanin neurons in the medial preoptic area govern parental behaviour

Sexual experience brings radical changes in how male mice behave with pups—virgin males attack them whereas mature fathers display parental care; here the authors identify a subset of hypothalamic neurons whose ablation leads to parental deficits in both males and females, and whose activation in virgin males suppresses aggression and induces pup grooming.

Zheng Wu
, Anita E. Autry
& Catherine G. Dulac

Article | 02 October 2013

Odour receptors and neurons for DEET and new insect repellents

The olfactory receptors and neurons that recognize the insect repellent DEET have been identified in Drosophila melanogaster, enabling identification of new insect repellents in a chemical screen and offering another research avenue against diseases transmitted by insects.

Pinky Kain
, Sean Michael Boyle
& Anandasankar Ray

Letter | 02 October 2013

A juvenile mouse pheromone inhibits sexual behaviour through the vomeronasal system

ESP22, a new pheromone produced by juvenile mice before puberty and released through the tears, activates neurons in the vomeronasal organ and inhibits mating behaviour in adult males towards animals expressing this signal.

David M. Ferrero
, Lisa M. Moeller
& Stephen D. Liberles

Letter | 28 April 2013

Non-redundant coding of aversive odours in the main olfactory pathway

Deletion of a single gene, Taar4, in mice abolishes aversion to low concentrations of volatile amines and to the odour of predator urine, indicating that individual olfactory receptor genes can affect odour perception.

Adam Dewan
, Rodrigo Pacifico
& Thomas Bozza

Letter | 24 April 2013

Random convergence of olfactory inputs in the Drosophila mushroom body

In Drosophila, olfactory sensory neurons project to spatially invariant loci (glomeruli) and stereotyped circuitry is maintained in projections to a brain centre thought to mediate innate behaviours; here it is shown that neurons of the mushroom body, a centre that translates olfactory information into learned behaviours, integrate input from an apparently random combination of glomeruli, which could allow the fly to contextualize novel sensory experiences.

Sophie J. C. Caron
, Vanessa Ruta
& Richard Axel

Letter | 23 December 2012

Asymmetric neurotransmitter release enables rapid odour lateralization in Drosophila

When an odour activates a fly′s antennae asymmetrically, more neurotransmitter is released from olfactory receptor neuron axon branches ipsilateral to the antenna than from contralateral branches. This causes ipsilateral central olfactory neurons to begin spiking earlier and at a higher rate than contralateral neurons, thereby enabling a walking fly to turn towards the odour.

Quentin Gaudry
, Elizabeth J. Hong
& Rachel I. Wilson

News & Views | 21 November 2012

Intimate neuronal whispers

It's a touching story of cohabitation and meaningful communication. Two neighbouring fruitfly neurons talk to each other not by means of synaptic junctions but by interactions through the surrounding electrical field. See Article p.66

Kazumichi Shimizu
& Mark Stopfer

Article | 21 November 2012

Non-synaptic inhibition between grouped neurons in an olfactory circuit

Olfactory receptor neurons of fruitflies are shown to communicate with one another through ephaptic interactions with significant impact on olfactory behaviour; the results indicate that ephaptic effects may be more widespread than previously appreciated.

Chih-Ying Su
, Karen Menuz
& John R. Carlson

News | 19 November 2012

The whiff of white could hide strong odours

Complex mixtures of many odours tend to smell the same.

Zoë Corbyn

News | 04 September 2012

Gene therapy restores sense of smell to mice

Cilia repair rescues olfactory function, but its potential in broader disorders is unclear.

Melissa Lee Phillips

News & Views | 15 August 2012

Circuits drive cell diversity

Neurons of the same type can show functional differences. It turns out that this diversity is in part the result of the cells' adaptation to their specific neural networks. See Letter p.375

Nathaniel Urban
& Shreejoy Tripathy

Letter | 22 July 2012

A biophysical signature of network affiliation and sensory processing in mitral cells

Functional heterogeneity within a class of neurons is investigated by comparing the intrinsic properties of pairs of mitral cells belonging to either the same or different glomerular circuits; this shows that neuronal excitability is stereotypic for mitral cells from the same olfactory network, indicating that local circuits are functionally adapted to process subtly distinct information.

Kamilla Angelo
, Ede A. Rancz
& Troy W. Margrie

News | 31 May 2012

'Old person smell' is real, but not necessarily offensive

A new study confirms that people, like many animals, easily recognize a unique—but not unpleasant—eau de elderly.

Ferris Jabr

Article | 18 March 2012

Teneurins instruct synaptic partner matching in an olfactory map

Two members of the Teneurin transmembrane protein family are shown to control the synaptic partner matching in the Drosophila olfactory system.

Weizhe Hong
, Timothy J. Mosca
& Liqun Luo

Article | 25 January 2012

Conditional modulation of spike-timing-dependent plasticity for olfactory learning

In the locust olfactory system, spike-timing-dependent plasticity acts as a synaptic ‘tag’ that labels only the synapses active in response to specific odorants, thus priming them for subsequent modulation of the plasticity rule.

Stijn Cassenaer
& Gilles Laurent

Letter | 18 January 2012

Neuron-type-specific signals for reward and punishment in the ventral tegmental area

Dopaminergic neurons in the mouse ventral tegmental area signal the difference between received and expected reward, whereas GABAergic neurons signal expected reward.

Jeremiah Y. Cohen
, Sebastian Haesler
& Naoshige Uchida

Article | 13 November 2011

Neuronal filtering of multiplexed odour representations

Optogenetic stimulation in the zebrafish olfactory bulb and downstream read out of activity in the homologue of olfactory cortex demonstrate how temporal filtering can extract specific components of neuronal codes.

Francisca Blumhagen
, Peixin Zhu
& Rainer W. Friedrich

News & Views | 12 October 2011

Fruity aphrodisiacs

Some fruit odours sexually arouse male fruitflies. The response is mediated by olfactory neurons that are sensitive to food smells and plug into the brain's neural circuit for sexual behaviour. See Letter p.236