Mushroom bodies

Last updated
Mushroom bodies visible in a Drosophila brain as two stalks. From Jenett et al., 2006 Drosophila melanogaster brain expression patterns.jpg
Mushroom bodies visible in a Drosophila brain as two stalks. From Jenett et al., 2006

The mushroom bodies or corpora pedunculata are a pair of structures in the brain of arthropods, including insects and crustaceans, [2] and some annelids (notably the ragworm Platynereis dumerilii ). [3] They are known to play a role in olfactory learning and memory. In most insects, the mushroom bodies and the lateral horn are the two higher brain regions that receive olfactory information from the antennal lobe via projection neurons. [4] They were first identified and described by French biologist Félix Dujardin in 1850. [5] [6]

Contents

Structure

Mushroom bodies are usually described as neuropils, i.e., as dense networks of neuronal processes (dendrite and axon terminals) and glia. They get their name from their roughly hemispherical calyx, a protuberance that is joined to the rest of the brain by a central nerve tract or peduncle.

Most of our current knowledge of mushroom bodies comes from studies of a few species of insect, especially the cockroach Periplaneta americana , the honey bee Apis mellifera , [7] the locust and the fruit fly Drosophila melanogaster . Studies of fruit fly mushroom bodies have been particularly important for understanding the genetic basis of mushroom body functioning, since their genome has been sequenced and a vast number of tools to manipulate their gene expression exist.

In the insect brain, the peduncles of the mushroom bodies extend through the midbrain. They are mainly composed of the long, densely packed nerve fibres of the Kenyon cells, the intrinsic neurons of the mushroom bodies. These cells have been found in the mushroom bodies of all species that have been investigated, though their number varies. Fruit flies, for example, have around 2,500, whereas cockroaches have about 200,000.

A locust brain dissection to expose the central brain and carry out electro-physiology recordings can be seen here. [8]

Evolutionary history

Historically, it was believed that only insects had mushroom bodies, because they were not present in crabs and lobsters. However, their discovery in the mantis shrimp in 2017 lead to the later conclusion [2] that the mushroom body is the ancestral state of all arthropods, and that this feature was later lost in crabs and lobsters. [2]

Function

Mushroom bodies are best known for their role in olfactory associative learning. These olfactory signals are received from dopaminergic, octopaminergic, cholinergic, serotonergic, and GABAergic neurons outside the MB. [9] They are largest in the Hymenoptera, which are known to have particularly elaborate control over olfactory behaviours. However, since mushroom bodies are also found in anosmic primitive insects, their role is likely to extend beyond olfactory processing. Anatomical studies suggest a role in the processing of visual and mechanosensory input in some species. [10] In Hymenoptera in particular, subregions of the mushroom body neuropil are specialized to receive olfactory, visual, or both types of sensory input. [11] In Hymenoptera, olfactory input is layered in the calyx. In ants, several layers can be discriminated, corresponding to different clusters of glomeruli in the antennal lobes, perhaps for processing different classes of odors. [4] [12] There are two main groups of projection neurons dividing the antennal lobe into two main regions, anterior and posterior. Projection neuron groups are segregated, innervating glomerular groups separately and sending axons by separate routes, either through the medial-antenno protocerebral tract (m-APT) or through the lateral-antenno protocerebral tract (l-APT), and connecting with two layers in the calyx of the mushroom bodies. In these layers the organization of the two efferent regions of the antennal lobe is represented topographically, establishing a coarse odotopic map of the antennal lobe in the region of the lip of the mushroom bodies. [4] [12]

Mushroom bodies are known to be involved in learning and memory, particularly for smell, and thus are the subject of current intense research. In larger insects, studies suggest that mushroom bodies have other learning and memory functions, like associative memory, sensory filtering, motor control, and place memory. Research implies that mushroom bodies generally act as a sort of coincidence detector, integrating multi-modal inputs [4] and creating novel associations, thus suggesting their role in learning and memory. [13] Recent work also shows evidence for the involvement of the mushroom body in innate olfactory behaviors through interactions with the lateral horn, [14] [15] possibly making use of the partially stereotyped sensory responses of the mushroom body output neurons (MBONs) across individuals. [16] Although the connections between the projection neurons and the Kenyon cells are random (i.e., not stereotyped across individuals), [17] the stereotypy in MBON responses is made possible by the dense convergence of many Kenyon cells onto a few MBONs along with other network properties. [16]

Information about odors may be encoded in the mushroom body by the identities of the responsive neurons as well as the timing of their spikes. [18] Experiments in locusts have shown that Kenyon cells have their activity synchronized to 20-Hz neural oscillations and are particularly responsive to projection neuron spikes at specific phases of the oscillatory cycle. [19]

Sleep

The neurons which receive signals from serotonergic and GABAergic neurons outside the MB produce wakefulness, and experimentally stimulating these serotonergic upstream neurons forces sleep. The target neurons in the MB are inhibited by serotonin, GABA, and the combination of both. On the other hand octopamine does not seem to affect the MB's sleep function. [9]

Drosophila melanogaster

Mushroom body lobes of D. melanogaster, with a/b, a'/b', and g neurons visible. From Davis, 2011 D. melanogaster mushroom body.png
Mushroom body lobes of D. melanogaster, with α/β, α’/β’, and γ neurons visible. From Davis, 2011

We know that mushroom body structures are important for olfactory learning and memory in Drosophila because their ablation destroys this function. [21] The mushroom body is also able to combine information from the internal state of the body and the olfactory input to determine innate behavior. [22] The exact roles of the specific neurons making up the mushroom bodies are still unclear. However, these structures are studied extensively because much is known about their genetic make-up. There are three specific classes of neurons that make up the mushroom body lobes: α/β, α’/β’, and γ neurons, which all have distinct gene expression. A topic of current research is which of these substructures in the mushroom body are involved in each phase and process of learning and memory. [23] Drosophila mushroom bodies are also often used to study learning and memory and are manipulated due to their relatively discrete nature. Typically, olfactory learning assays consist of exposing flies to two odors separately; one is paired with electric shock pulses (the conditioned stimulus, or CS+), and the second is not (unconditioned stimulus, or US). After this training period, flies are placed in a T-maze with the two odors placed individually on either end of the horizontal ‘T’ arms. The percent of flies that avoid the CS+ is calculated, with high avoidance considered evidence of learning and memory. [24]

Cellular memory traces

Recent studies combining odor conditioning and cellular imaging have identified six memory traces that coincide with molecular changes in the Drosophila olfactory system. Three of these traces are associated with early forming behavioral memory. One such trace was visualized in the antennal lobe (AL) by synapto-pHluorin reporter molecules. Immediately after conditioning, an additional set of projection neurons in a set of eight glomeruli in the AL becomes synaptically activated by the conditioned odor, and lasts for only 7 minutes. [25] A second trace is detectable by GCaMP expression, and thus an increase in Ca2+ influx, in the α’/β’ axons of the mushroom body neurons. [26] This is a longer-lasting trace, present for up to one hour following conditioning. The third memory trace is the reduction of activity of the anterior-paired lateral neuron, which acts as a memory formation suppressor through one of its inhibitory GABAergic receptors. Decrease in calcium response of APL neurons and subsequent decrease in GABA release onto the mushroom bodies persisted up to 5 minutes after odor conditioning. [27]

The intermediate term memory trace is dependent on expression of the amn gene located in dorsal paired medial neurons. An increase in calcium influx and synaptic release that innervates the mushroom bodies becomes detectable approximately 30 minutes after pairing of electric shock with an odor, and persists for at least an hour. [28] Both long-term memory traces that have been mapped depend on activity and protein synthesis of CREB and CaMKII, and only exist after spaced conditioning. The first trace is detected in α/β neurons between 9 and 24 hours after conditioning, and is characterized by an increase in calcium influx in response to the conditioned odor. [29] The second long-term memory trace forms in the γ mushroom bodies and is detected by increase calcium influx between 18 and 24 hours after conditioning [30]

cAMP dynamics

Cyclic adenosine monophosphate (cAMP or cyclic AMP) is a second messenger that has been implicated in facilitating mushroom body calcium influx in Drosophila melanogaster mushroom body neurons. cAMP elevation induces presynaptic plasticity in Drosophila. cAMP levels are affected by both neurotransmitters, such as dopamine and octopamine, and odors themselves. Dopamine and octopamine are released by mushroom body interneurons, while odors directly activate neurons in the olfactory pathway, causing calcium influx through voltage-gated calcium channels. [31]

In a classical conditioning paradigm, pairing neuronal depolarization (via acetylcholine application to represent the odor or CS) with subsequent dopamine application (to represent the shock or US), results in a synergistic increase in cAMP in the mushroom body lobes. [31] These results suggest that the mushroom body lobes are a critical site of CS/US integration via the action of cAMP. This synergistic effect was originally observed in Aplysia, where pairing calcium influx with activation of G protein signaling by serotonin generates a similar synergistic increase in cAMP. [32]

Additionally, this synergistic increase in cAMP is mediated by and dependent on rutabaga adenylyl cyclase (rut AC), which is sensitive to both calcium (which results from voltage-gated calcium channel opening by odors) and G protein stimulation (caused by dopamine). [31] While a forward pairing of neuronal depolarization and dopamine, (acetylcholine followed by dopamine) results in a synergistic increase in cAMP, a forward pairing of neuronal depolarization and octopamine produces a sub-additive effect on cAMP. [31] More specifically, this means that this pairing produces significantly less cAMP than the sum of each stimulus individually in the lobes. Therefore, rut AC in mushroom body neurons works as a coincidence detector with dopamine and octopamine functioning bidirectionally to affect cAMP levels. [31]

PKA dynamics

Spatial regulation of PKA dynamics in Drosophila mushroom body. PKA Dynamics.png
Spatial regulation of PKA dynamics in Drosophila mushroom body.

Protein kinase A (PKA) has been found to play an important role in learning and memory in Drosophila. [33] When calcium enters a cell and binds with calmodulin, it stimulates adenylate cyclase (AC), which is encoded by the rutabaga gene (rut). [34] This AC activation increases the concentration of cAMP, which activates PKA. [34] When dopamine, an aversive olfactory stimulant, is applied it activates PKA specifically in the vertical mushroom body lobes. [34] This spatial specificity is regulated by the dunce (dnc) PDE, a cAMP-specific phosphodiesterase. If the dunce gene is abolished, as found in the dnc mutant, the spatial specificity is not maintained. In contrast, an appetitive stimulation created by an octopamine application increases PKA in all lobes. [34] In the rut mutant, a genotype in which the rutabaga is abolished, the responses to both dopamine and octopamine were greatly reduced and close to experimental noise.

Acetylcholine, which represents the conditioned stimulus, leads to a strong increase in PKA activation compared to stimulation with dopamine or octopamine alone. [34] This reaction is abolished in rut mutants, which demonstrates that PKA is essential for sensory integration. [34] The specificity of activation of the alpha lobe in the presence of dopamine is maintained when dopamine is in combination with acetylcholine. [34] Essentially, during a conditioning paradigm when a conditioned stimulus is paired with an unconditioned stimulus, PKA exhibits heightened activation. This shows that PKA is required for conditioned learning in Drosophila melanogaster .

Apis mellifera

Stimulus output responses are the product of pairs of excitation and inhibition. This is the same pattern of organisation as with mammals' brains. These patterns may, as with mammals, precede action. As of 2021 this is an area only recently elucidated by Zwaka et al 2018, Duer et al 2015, and Paffhausen et al 2020. [7]

See also

Related Research Articles

<span class="mw-page-title-main">Monoamine neurotransmitter</span> Monoamine that acts as a neurotransmitter or neuromodulator

Monoamine neurotransmitters are neurotransmitters and neuromodulators that contain one amino group connected to an aromatic ring by a two-carbon chain (such as -CH2-CH2-). Examples are dopamine, norepinephrine and serotonin.

<span class="mw-page-title-main">Olfactory bulb</span> Neural structure

The olfactory bulb is a neural structure of the vertebrate forebrain involved in olfaction, the sense of smell. It sends olfactory information to be further processed in the amygdala, the orbitofrontal cortex (OFC) and the hippocampus where it plays a role in emotion, memory and learning. The bulb is divided into two distinct structures: the main olfactory bulb and the accessory olfactory bulb. The main olfactory bulb connects to the amygdala via the piriform cortex of the primary olfactory cortex and directly projects from the main olfactory bulb to specific amygdala areas. The accessory olfactory bulb resides on the dorsal-posterior region of the main olfactory bulb and forms a parallel pathway. Destruction of the olfactory bulb results in ipsilateral anosmia, while irritative lesions of the uncus can result in olfactory and gustatory hallucinations.

<span class="mw-page-title-main">Tyramine</span> Chemical compound

Tyramine, also known under several other names, is a naturally occurring trace amine derived from the amino acid tyrosine. Tyramine acts as a catecholamine releasing agent. Notably, it is unable to cross the blood-brain barrier, resulting in only non-psychoactive peripheral sympathomimetic effects following ingestion. A hypertensive crisis can result, however, from ingestion of tyramine-rich foods in conjunction with the use of monoamine oxidase inhibitors (MAOIs).

<span class="mw-page-title-main">Olfactory receptor neuron</span> Transduction nerve cell within the olfactory system

An olfactory receptor neuron (ORN), also called an olfactory sensory neuron (OSN), is a sensory neuron within the olfactory system.

<span class="mw-page-title-main">CREB</span> Class of proteins

CREB-TF is a cellular transcription factor. It binds to certain DNA sequences called cAMP response elements (CRE), thereby increasing or decreasing the transcription of the genes. CREB was first described in 1987 as a cAMP-responsive transcription factor regulating the somatostatin gene.

<span class="mw-page-title-main">Interneuron</span> Neurons that are not motor or sensory

Interneurons are neurons that connect to brain regions, i.e. not direct motor neurons or sensory neurons. Interneurons are the central nodes of neural circuits, enabling communication between sensory or motor neurons and the central nervous system (CNS). They play vital roles in reflexes, neuronal oscillations, and neurogenesis in the adult mammalian brain.

<span class="mw-page-title-main">Octopamine</span> Group of stereoisomers

Octopamine (molecular formula C8H11NO2; also known as OA, and also norsynephrine, para-octopamine and others) is an organic chemical closely related to norepinephrine, and synthesized biologically by a homologous pathway. Octopamine is often considered the major "fight-or-flight" neurohormone of invertebrates. Its name is derived from the fact that it was first identified in the salivary glands of the octopus.

The antennal lobe is the primary olfactory brain area in insects. The antennal lobe is a sphere-shaped deutocerebral neuropil in the brain that receives input from the olfactory sensory neurons in the antennae and mouthparts. Functionally, it shares some similarities with the olfactory bulb in vertebrates. The anatomy and physiology function of the insect brain can be studied by dissecting open the insect brain and imaging or carrying out in vivo electrophysiological recordings from it.

Martin Heisenberg is a German neurobiologist and geneticist. Before his retirement in 2008, he held the professorial chair for genetics and neurobiology at the Bio Centre of the University of Würzburg. Since then, he continues his research with a senior professorship at the Rudolf Virchow Center of the University of Würzburg. Heisenberg studied chemistry and molecular biology in Munich, Tübingen and Pasadena. In 1975 he became Professor of genetics and neurobiology at the University of Würzburg. Heisenberg's work has focused on the neurogenetics of Drosophila, with the aim of investigating the genetic foundations of the Drosophila brain by studying the effect of genetic mutations on brain function. In addition, Heisenberg contributed a number of essays on the topics of science in society, perception, as well as the question of the freedom of the will. He was elected as a member of the Leopoldina in 1989.

Olfactory fatigue, also known as odor fatigue, olfactory adaptation, and noseblindness, is the temporary, normal inability to distinguish a particular odor after a prolonged exposure to that airborne compound. For example, when entering a restaurant initially the odor of food is often perceived as being very strong, but after time the awareness of the odor normally fades to the point where the smell is not perceptible or is much weaker. After leaving the area of high odor, the sensitivity is restored with time. Anosmia is the permanent loss of the sense of smell, and is different from olfactory fatigue.

<span class="mw-page-title-main">TAAR1</span> Protein-coding gene in the species Homo sapiens

Trace amine-associated receptor 1 (TAAR1) is a trace amine-associated receptor (TAAR) protein that in humans is encoded by the TAAR1 gene. TAAR1 is an intracellular amine-activated Gs-coupled and Gq-coupled G protein-coupled receptor (GPCR) that is primarily expressed in several peripheral organs and cells, astrocytes, and in the intracellular milieu within the presynaptic plasma membrane of monoamine neurons in the central nervous system (CNS). TAAR1 was discovered in 2001 by two independent groups of investigators, Borowski et al. and Bunzow et al. TAAR1 is one of six functional human trace amine-associated receptors, which are so named for their ability to bind endogenous amines that occur in tissues at trace concentrations. TAAR1 plays a significant role in regulating neurotransmission in dopamine, norepinephrine, and serotonin neurons in the CNS; it also affects immune system and neuroimmune system function through different mechanisms.

Kenyon cells are the intrinsic neurons of the mushroom body, a neuropil found in the brains of most arthropods and some annelids. They were first described by F. C. Kenyon in 1896. The number of Kenyon cells in an organism varies greatly between species. For example, in the fruit fly, Drosophila melanogaster, there are about 2,500 Kenyon cells per mushroom body, while in cockroaches there are about 230,000.

<span class="mw-page-title-main">Sense of smell</span> Sense that detects smells

The sense of smell, or olfaction, is the special sense through which smells are perceived. The sense of smell has many functions, including detecting desirable foods, hazards, and pheromones, and plays a role in taste.

Olfactory memory refers to the recollection of odors. Studies have found various characteristics of common memories of odor memory including persistence and high resistance to interference. Explicit memory is typically the form focused on in the studies of olfactory memory, though implicit forms of memory certainly supply distinct contributions to the understanding of odors and memories of them. Research has demonstrated that the changes to the olfactory bulb and main olfactory system following birth are extremely important and influential for maternal behavior. Mammalian olfactory cues play an important role in the coordination of the mother infant bond, and the following normal development of the offspring. Maternal breast odors are individually distinctive, and provide a basis for recognition of the mother by her offspring.

Mosaic analysis with a repressible cell marker, or MARCM, is a genetics technique for creating individually labeled homozygous cells in an otherwise heterozygous Drosophila melanogaster. It has been a crucial tool in studying the development of the Drosophila nervous system. This technique relies on recombination during mitosis mediated by FLP-FRT recombination. As one copy of a gene, provided by the balancer chromosome, is often enough to rescue a mutant phenotype, MARCM clones can be used to study a mutant phenotype in an otherwise wildtype animal.

The lateral horn is one of the two areas of the insect brain where projection neurons of the antennal lobe send their axons. The other area is the mushroom body. Several morphological classes of neurons in the lateral horn receive olfactory information through the projection neurons.

A Drosophila connectome is a list of neurons in the Drosophila melanogaster nervous system, and the chemical synapses between them. The fly's nervous system consists of the brain plus the ventral nerve cord, and both are known to differ considerably between male and female. Dense connectomes have been completed for the female adult brain, the male nerve cord, and the female larval stage. The available connectomes show only chemical synapses - other forms of inter-neuron communication such as gap junctions or neuromodulators are not represented. Drosophila is the most complex creature with a connectome, which had only been previously obtained for three other simpler organisms, first C. elegans. The connectomes have been obtained by the methods of neural circuit reconstruction, which over the course of many years worked up through various subsets of the fly brain to the almost full connectomes that exist today.

<span class="mw-page-title-main">Insect olfaction</span> Function of chemical receptors

Insect olfaction refers to the function of chemical receptors that enable insects to detect and identify volatile compounds for foraging, predator avoidance, finding mating partners and locating oviposition habitats. Thus, it is the most important sensation for insects. Most important insect behaviors must be timed perfectly which is dependent on what they smell and when they smell it. For example, olfaction is essential for locating host plants and hunting prey in many species of insects, such as the moth Deilephila elpenor and the wasp Polybia sericea, respectively.

<span class="mw-page-title-main">Vanessa Ruta</span> American neuroscientist

Vanessa Julia Ruta is an American neuroscientist known for her work on the structure and function of chemosensory circuits underlying innate and learned behaviors in the fly Drosophila melanogaster. She is the Gabrielle H. Reem and Herbert J. Kayden Associate Professor and Head of the Laboratory of Neurophysiology and Behavior at The Rockefeller University and, as of 2021, an Investigator of the Howard Hughes Medical Institute.

<span class="mw-page-title-main">Reinhard F. Stocker</span> Swiss biologist

Reinhard F. Stocker is a Swiss biologist. He pioneered the analysis of the sense of smell and taste in higher animals, using the fly Drosophila melanogaster as a study case. He provided a detailed account of the anatomy and development of the olfactory system, in particular across metamorphosis, for which he received the Théodore-Ott-Prize of the Swiss Academy of Medical Sciences in 2007, and pioneered the use of larval Drosophila for the brain and behavioural sciences.

References

  1. Jenett A.; Schindelin J. E.; Heisenberg M. (2006). "The Virtual Insect Brain protocol: creating and comparing standardized neuroanatomy". BMC Bioinformatics . 7: 544. doi: 10.1186/1471-2105-7-544 . PMC   1769402 . PMID   17196102.
  2. 1 2 3 Strausfeld, Nicholas James; Wolff, Gabriella Hanna; Sayre, Marcel Ethan (2020-03-03). "Mushroom body evolution demonstrates homology and divergence across Pancrustacea". eLife. 9. doi: 10.7554/eLife.52411 . ISSN   2050-084X. PMC   7054004 . PMID   32124731.
  3. Tomer, R.; Denes, A. S.; Tessmar-Raible, K.; Arendt, D. (2010). "Profiling by image registration reveals common origin of annelid mushroom bodies and vertebrate pallium". Cell. 142 (5): 800–809. doi: 10.1016/j.cell.2010.07.043 . PMID   20813265. S2CID   917306.
  4. 1 2 3 4 Gronenberg, W.; López-Riquelme, G.O. (February 2014). "Multisensory convergence in the mushroom bodies of ants and bees". Acta Biologica Hungarica. 55 (1–4): 31–37. doi:10.1556/ABiol.55.2004.1-4.5. PMID   15270216.
  5. Dujardin, F. (1850). "Mémoire sur le système nerveux des insectes". Ann. Sci. Nat. Zool. 14: 195–206.
  6. Strausfeld N. J.; Hansen L; Li Y; Gomez R. S.; Ito K. (1998). "Evolution, discovery, and interpretations of arthropod mushroom bodies". Learn. Mem. 5 (1–2): 11–37. doi:10.1101/lm.5.1.11. PMC   311242 . PMID   10454370.
  7. 1 2 Menzel, Randolf (2020-08-13). "A short history of studies on intelligence and brain in honeybees". Apidologie . 52 (1). INRAE & DI (Springer): 23–34. doi: 10.1007/s13592-020-00794-x . ISSN   0044-8435. S2CID   221111734.
  8. "Dissecting insect brain for in vivo electrophysiology". YouTube .
  9. 1 2 Helfrich-Förster, Charlotte (2018-01-07). "Sleep in Insects". Annual Review of Entomology . 63 (1). Annual Reviews: 69–86. doi: 10.1146/annurev-ento-020117-043201 . ISSN   0066-4170. PMID   28938081.
  10. Zars, Troy (December 2000). "Behavioral functions of the insect mushroom bodies". Curr Opin Neurobiol. 10 (6): 790–5. doi:10.1016/S0959-4388(00)00147-1. PMID   11240291. S2CID   5946392.
  11. Mobbs, P. G. (1982). "The Brain of the Honeybee Apis Mellifera. I. The Connections and Spatial Organization of the Mushroom Bodies". Philosophical Transactions of the Royal Society of London B. 298 (1091): 309–354. Bibcode:1982RSPTB.298..309M. doi:10.1098/rstb.1982.0086.
  12. 1 2 López-Riquelme, G.O. (June 2014). "Odotopic afferent representation of the glomerular antennal lobe organization in the mushroom bodies of ants (Hymenoptera: Formicidae): Comparisons between two species". TIP Revista Especializada en Ciencias Químico-Biológicas. 15 (1): 15–31. doi: 10.1016/S1405-888X(14)70317-1 .
  13. Tully, T; Quinn, WG (September 1985). "Classical conditioning and retention in normal and mutant Drosophila melanogaster". J Comp Physiol A. 157 (2): 263–77. doi:10.1007/bf01350033. PMID   3939242. S2CID   13552261.
  14. Dolan, Michael-John; Frechter, Shahar; Bates, Alexander Shakeel; Dan, Chuntao; Huoviala, Paavo; Roberts, Ruairí JV; Schlegel, Philipp; Dhawan, Serene; Tabano, Remy; Dionne, Heather; Christoforou, Christina; Close, Kari; Sutcliffe, Ben; Giuliani, Bianca; Li, Feng; Costa, Marta; Ihrke, Gudrun; Meissner, Geoffrey Wilson; Bock, Davi D; Aso, Yoshinori; Rubin, Gerald M; Jefferis, Gregory SXE (21 May 2019). "Neurogenetic dissection of the Drosophila lateral horn reveals major outputs, diverse behavioural functions, and interactions with the mushroom body". eLife. 8: e43079. doi: 10.7554/eLife.43079 . ISSN   2050-084X. PMC   6529221 . PMID   31112130.
  15. Lewis, LP; Siju, KP; Aso, Y; Friedrich, AB; Bulteel, AJ; Rubin, GM; Grunwald Kadow, IC (31 August 2015). "A Higher Brain Circuit for Immediate Integration of Conflicting Sensory Information in Drosophila". Current Biology. 25 (17): 2203–14. doi: 10.1016/j.cub.2015.07.015 . PMID   26299514. S2CID   16276500.
  16. 1 2 Mittal, Aarush Mohit; Gupta, Diksha; Singh, Amrita; Lin, Andrew C.; Gupta, Nitin (24 February 2020). "Multiple network properties overcome random connectivity to enable stereotypic sensory responses". Nature Communications. 11 (1): 1023. Bibcode:2020NatCo..11.1023M. doi:10.1038/s41467-020-14836-6. PMC   7039968 . PMID   32094345.
  17. Caron, SJ; Ruta, V; Abbott, LF; Axel, R (2 May 2013). "Random convergence of olfactory inputs in the Drosophila mushroom body". Nature. 497 (7447): 113–7. Bibcode:2013Natur.497..113C. doi:10.1038/nature12063. PMC   4148081 . PMID   23615618.
  18. Gupta, Nitin; Stopfer, Mark (6 October 2014). "A temporal channel for information in sparse sensory coding". Current Biology. 24 (19): 2247–56. doi:10.1016/j.cub.2014.08.021. PMC   4189991 . PMID   25264257.
  19. Gupta, Nitin; Singh, Swikriti Saran; Stopfer, Mark (2016-12-15). "Oscillatory integration windows in neurons". Nature Communications. 7: 13808. Bibcode:2016NatCo...713808G. doi:10.1038/ncomms13808. ISSN   2041-1723. PMC   5171764 . PMID   27976720.
  20. Davis, Ronald (2011). "Traces of Drosophila Memory". Neuron. 70 (1): 8–19. doi:10.1016/j.neuron.2011.03.012. PMC   3374581 . PMID   21482352.
  21. McGuire, Sean; Le, Phuong; Davis, Ronald (August 2001). "The role of Drosophila mushroom body signaling in olfactory memory". Science. 17 (293): 1330–33. Bibcode:2001Sci...293.1330M. doi: 10.1126/science.1062622 . PMID   11397912. S2CID   23489877.
  22. Bräcker, L. B.; Siju, K. P.; Varela, N.; Aso, Y.; Zhang, M.; Hein, I.; Kadow, I. C. G. (2013). "Essential role of the mushroom body in context-dependent CO2 avoidance in Drosophila". Current Biology. 23 (13): 1228–1234. doi: 10.1016/j.cub.2013.05.029 . PMID   23770186. S2CID   15112681.
  23. Yildizoglu, Tugce; Weislogel, Jan-Marek; Mohammad, Farhan; Chan, Edwin S.-Y.; Assam, Pryseley N.; Claridge-Chang, Adam (2015-12-08). "Estimating Information Processing in a Memory System: The Utility of Meta-analytic Methods for Genetics". PLOS Genet. 11 (12): e1005718. doi: 10.1371/journal.pgen.1005718 . ISSN   1553-7404. PMC   4672901 . PMID   26647168.
  24. Akalal, David-Benjamin; Wilson, Curtis; Zong, Lin; Tanaka, Nobuaki; Ito, Kei; Davis, Ronald (September 2006). "Roles for Drosophila mushroom body neurons in olfactory learning and memory". Learning and Memory. 13 (1): 659–68. doi:10.1101/lm.221206. PMC   1783621 . PMID   16980542.
  25. Yu, Dinghui; Ponomarev, Artem; Davis, Ronald (May 2004). "Altered representation of the spatial code for odors after olfactory Classical conditioning; memory trace formation by synaptic recruitment". Neuron. 42 (3): 437–49. doi: 10.1016/S0896-6273(04)00217-X . PMID   15134640. S2CID   5859632.
  26. Wang, Yalin; Mamira, Akira; Chiang, Ann-shyn; Zhong, Yi (April 2008). "Imaging of an early memory trace in the Drosophila mushroom body". The Journal of Neuroscience. 28 (17): 4368–76. doi:10.1523/jneurosci.2958-07.2008. PMC   3413309 . PMID   18434515.
  27. Xu, Liu; Davis, Ronald (January 2009). "The GABAergic anterior paired lateral neuron suppresses and is suppressed by olfactory learning". Nature Neuroscience. 12 (1): 53–59. doi:10.1038/nn.2235. PMC   2680707 . PMID   19043409.
  28. Yu, Dinghui; Keene, Alex (December 2005). "Drosophila DPM neurons form a delayed and branch-specific memory trace after olfactory classical conditioning". Cell. 123 (5): 945–57. doi: 10.1016/j.cell.2005.09.037 . PMID   16325586. S2CID   14152868.
  29. Yu, Dinghui; Akalal, Benjamin-David (December 2006). "Drosophila a/b mushroom body neurons form a branch-specific, long-term cellular memory trace after spaced olfactory conditioning". Neuron. 52 (1): 845–55. doi:10.1016/j.neuron.2006.10.030. PMC   1779901 . PMID   17145505.
  30. Akalal, Benjamin-David; Yu, Dinghui (December 2010). "A Late-Phase, Long-Term Memory Trace Forms in the γ Neurons of Drosophila Mushroom Bodies after Olfactory Classical Conditioning". The Journal of Neuroscience. 30 (49): 16699–16708. doi:10.1523/jneurosci.1882-10.2010. PMC   3380342 . PMID   21148009.
  31. 1 2 3 4 5 Tomchik, Seth; Davis, Ronald (November 2009). "Dynamics of Learning-Related cAMP Signaling and stimulus Integration in the Drosophila Olfactory Pathway". Neuron. 64 (4): 510–21. doi:10.1016/j.neuron.2009.09.029. PMC   4080329 . PMID   19945393.
  32. Abrams, Thomas; Karl, Kevin; Kandel, Eric (September 1991). "Biochemical studies of stimulus convergence during classical conditioning in Aplysia: dual regulation of adenylate cyclase by Ca2+/calmodulin and transmitter". The Journal of Neuroscience. 11 (9): 2655–65. doi:10.1523/JNEUROSCI.11-09-02655.1991. PMC   6575265 . PMID   1679120. S2CID   16477962.
  33. Skoulakis, EM; Kalderon, D; Davis, RL (1993). "Preferential expression in mushroom bodies of the catalytic subunit of protein kinase A and its role in learning and memory". Neuron. 11 (2): 197–201. doi:10.1016/0896-6273(93)90178-t. PMID   8352940. S2CID   23105390.
  34. 1 2 3 4 5 6 7 Gervasi, Nicolas; Tchènio, Paul; Preat, Thomas (February 2010). "PKA Dynamics in a Drosophila Learning Center: Coincidence Detection by Rutabaga Adenylyl Cyclase and Spatial Regulation by Dunce Phosphodiesterase". Neuron. 65 (4): 516–529. doi: 10.1016/j.neuron.2010.01.014 . PMID   20188656. S2CID   14318460.

Further reading