scholarly journals Drosulfakinin signaling in fruitless circuitry antagonizes P1 neurons to regulate sexual arousal in Drosophila

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Shunfan Wu ◽  
Chao Guo ◽  
Huan Zhao ◽  
Mengshi Sun ◽  
Jie Chen ◽  
...  
Keyword(s):  
Sexual Behaviors ◽  
Single Neuron ◽  
Neural Circuits ◽  
Neural Circuit ◽  
Neural Substrates ◽  
Internal States ◽  
And Function ◽  
Key Steps ◽  
Male Specific ◽  
Command Center

Abstract Animals perform or terminate particular behaviors by integrating external cues and internal states through neural circuits. Identifying neural substrates and their molecular modulators promoting or inhibiting animal behaviors are key steps to understand how neural circuits control behaviors. Here, we identify the Cholecystokinin-like peptide Drosulfakinin (DSK) that functions at single-neuron resolution to suppress male sexual behavior in Drosophila. We found that Dsk neurons physiologically interact with male-specific P1 neurons, part of a command center for male sexual behaviors, and function oppositely to regulate multiple arousal-related behaviors including sex, sleep and spontaneous walking. We further found that the DSK-2 peptide functions through its receptor CCKLR-17D3 to suppress sexual behaviors in flies. Such a neuropeptide circuit largely overlaps with the fruitless-expressing neural circuit that governs most aspects of male sexual behaviors. Thus DSK/CCKLR signaling in the sex circuitry functions antagonistically with P1 neurons to balance arousal levels and modulate sexual behaviors.

scholarly journals The Drosophila Larval Locomotor Circuit Provides a Model to Understand Neural Circuit Development and Function

2021 ◽  
Vol 15 ◽  
Author(s):  
Iain Hunter ◽  
Bramwell Coulson ◽  
Aref Arzan Zarin ◽  
Richard A. Baines
Keyword(s):  
Neural Circuits ◽  
Neural Circuit ◽  
Fruit Fly ◽  
Model Organisms ◽  
Generic Model ◽  
Critical Periods ◽  
Neuroscience Research ◽  
Circuit Development ◽  
And Function ◽  
Model Circuit

It is difficult to answer important questions in neuroscience, such as: “how do neural circuits generate behaviour?,” because research is limited by the complexity and inaccessibility of the mammalian nervous system. Invertebrate model organisms offer simpler networks that are easier to manipulate. As a result, much of what we know about the development of neural circuits is derived from work in crustaceans, nematode worms and arguably most of all, the fruit fly, Drosophila melanogaster. This review aims to demonstrate the utility of the Drosophila larval locomotor network as a model circuit, to those who do not usually use the fly in their work. This utility is explored first by discussion of the relatively complete connectome associated with one identified interneuron of the locomotor circuit, A27h, and relating it to similar circuits in mammals. Next, it is developed by examining its application to study two important areas of neuroscience research: critical periods of development and interindividual variability in neural circuits. In summary, this article highlights the potential to use the larval locomotor network as a “generic” model circuit, to provide insight into mammalian circuit development and function.

scholarly journals Cytosolic PSD-95 Interactor Alters Functional Organization of Neural Circuits and AMPA Receptor Signaling Independent of PSD-95 Binding

2020 ◽  
pp. 1-72
Author(s):  
Ana R. Rodriguez ◽  
Erin D. Anderson ◽  
Kate M. O’Neill ◽  
Przemyslaw P. McEwan ◽  
Nicholas F. Vigilante ◽  
...  
Keyword(s):  
Ampa Receptor ◽  
Microelectrode Array ◽  
Neural Circuits ◽  
Neural Circuit ◽  
Functional Organization ◽  
Protein Localization ◽  
Postsynaptic Density ◽  
Brain Regions ◽  
Receptor Signaling ◽  
And Function

Cytosolic PSD-95 interactor (cypin) regulates many aspects of neuronal development and function, ranging from dendritogenesis to synaptic protein localization. While it is known that removal of postsynaptic density protein-95 (PSD-95) from the postsynaptic density decreases synaptic NMDA receptors and that cypin overexpression protects neurons from NMDA-induced toxicity, little is known about cypin’s role in AMPA receptor clustering and function. Experimental work shows that cypin overexpression decreases PSD-95 levels in synaptosomes and the PSD, decreases PSD-95 clusters/μm2, and increases mEPSC frequency. Analysis of microelectrode array (MEA) data demonstrates that cypin or cypinΔPDZ overexpression increases sensitivity to CNQX and AMPA receptor mediated decreases in spike waveform properties. Network-level analysis of MEA data reveals that cypinΔPDZ overexpression causes networks to be resilient to CNQX-induced changes in local efficiency. Incorporating these findings into a computational model of a neural circuit demonstrates a role for AMPA receptors in cypin-promoted changes to networks and shows that cypin increases firing rate while changing network functional organization, suggesting cypin overexpression facilitates information relay but modifies how information is encoded among brain regions. Our data show that cypin promotes changes to AMPA receptor signaling independent of PSD-95 binding, shaping neural circuits and output to regions beyond the hippocampus.

Neural Circuits of Sexual Behavior inCaenorhabditis elegans

2018 ◽  
Vol 41 (1) ◽  
pp. 349-369 ◽  
Author(s):  
Scott W. Emmons
Keyword(s):  
Nervous System ◽  
Sex Differences ◽  
Sexual Behaviors ◽  
Neural Circuits ◽  
Egg Laying ◽  
Synaptic Connectivity ◽  
Comprehensive Description ◽  
C Elegans ◽  
Shared Component ◽  
Male Specific

The recently determined connectome of the Caenorhabditis elegans adult male, together with the known connectome of the hermaphrodite, opens up the possibility for a comprehensive description of sexual dimorphism in this species and the identification and study of the neural circuits underlying sexual behaviors. The C. elegans nervous system consists of 294 neurons shared by both sexes plus neurons unique to each sex, 8 in the hermaphrodite and 91 in the male. The sex-specific neurons are well integrated within the remainder of the nervous system; in the male, 16% of the input to the shared component comes from male-specific neurons. Although sex-specific neurons are involved primarily, but not exclusively, in controlling sex-unique behavior—egg-laying in the hermaphrodite and copulation in the male—these neurons act together with shared neurons to make navigational choices that optimize reproductive success. Sex differences in general behaviors are underlain by considerable dimorphism within the shared component of the nervous system itself, including dimorphism in synaptic connectivity.

scholarly journals Extreme stiffness of neuronal synapses and implications for synaptic adhesion and plasticity

2020 ◽  
Author(s):  
Ju Yang ◽  
Nicola Mandriota ◽  
Steven Glenn Harrellson ◽  
John Anthony Jones-Molina ◽  
Rafael Yuste ◽  
...  
Keyword(s):  
Structural Changes ◽  
Neural Circuits ◽  
Neural Circuit ◽  
Critical Role ◽  
Theoretical Models ◽  
Cell Types ◽  
Long Term Potentiation ◽  
Biophysical Model ◽  
And Function ◽  
Circuit Function

AbstractSynapses play a critical role in neural circuits, and they are potential sites for learning and memory. Maintenance of synaptic adhesion is critical for neural circuit function, however, biophysical mechanisms that help maintain synaptic adhesion are not clear. Studies with various cell types demonstrated the important role of stiffness in cellular adhesions. Although synaptic stiffness could also play a role in synaptic adhesion, stiffnesses of synapses are difficult to characterize due to their small size and challenges in verifying synapse identity and function. To address these challenges, we have developed an experimental platform that combines atomic force microscopy, fluorescence microscopy, and transmission electron microscopy. Here, using this platform, we report that functional, mature, excitatory synapses had an average elastic modulus of approximately 200 kPa, two orders of magnitude larger than that of the brain tissue, suggesting stiffness might have a role in synapse function. Similar to various functional and anatomical features of neural circuits, synaptic stiffness had a lognormal-like distribution, hinting a possible regulation of stiffness by processes involved in neural circuit function. In further support of this possibility, we observed that synaptic stiffness was correlated with spine size, a quantity known to correlate with synaptic strength. Using established stages of the long-term potentiation timeline and theoretical models of adhesion cluster dynamics, we developed a biophysical model of the synapse that not only explains extreme stiffness of synapses, their statistical distribution, and correlation with spine size, but also offers an explanation to how early biomolecular and structural changes during functional potentiation could lead to strengthening of synaptic adhesion. According to this model, synaptic stiffness serves as an indispensable physical messenger, feeding information back to synaptic adhesion molecules to facilitate maintenance of synaptic adhesion.

scholarly journals Hunchback activates Bicoid in post-mitotic Pair1 neurons to regulate synapse number

2021 ◽  
Author(s):  
Kristen M Lee ◽  
Amanda M Linskens ◽  
Chris Q Doe
Keyword(s):  
Transcription Factor ◽  
Transcription Factors ◽  
Neural Circuits ◽  
Neural Circuit ◽  
Anatomical Location ◽  
Mature Neuron ◽  
Synapse Density ◽  
And Function ◽  
And Behavior ◽  
Homeodomain Transcription Factors

The proper formation and function of neural circuits is crucial for cognition, sensation, and behavior. Neural circuits are highly-specific, and this specificity is dependent on neurons developing key features of their individual identities: morphology, anatomical location, molecular expression and biophysiological properties. Previous research has demonstrated that a neurons identity is, in part, generated by the temporal transcription window the neuron is born in, and the homeodomain transcription factors expressed in the mature neuron. However, whether temporal transcription factors and homeodomain transcription factors regulate neural circuit formation, maintenance and function remains unknown. Here, we utilize a well-characterized neural circuit in the Drosophila larvae, the Pair1 neuron. We determined that in the Pair1 neuron, the temporal transcription factor Hunchback activates the homeodomain transcription factor Bicoid (Bcd). Both Hunchback and Bcd are expressed in Pair1 throughout larval development. Interestingly, Hunchback and Bcd were not required in Pair1 for neurotransmitter identity or axonal morphology, but were required for synapse density. We found that these transcription factors were functioning post-mitotically in Pair1 to regulate synapse density. Additionally, knocking down Hunchback and Bcd in Pair1 neurons disrupted the behavioral output of the circuit. We utilized the genetic tool TransTango to determine that Hunchback function in Pair1 is to repress forming synapses with erroneous neurons. To our knowledge, these data are the first to show Hunchback activating Bcd expression, as well as the first to demonstrate a role for Hunchback and Bcd post-mitotically.

scholarly journals Reverse Engineering and Robotics as Tools for Analyzing Neural Circuits

2021 ◽  
Vol 14 ◽  
Author(s):  
Ioannis Pisokas
Keyword(s):  
Reverse Engineering ◽  
Single Neuron ◽  
Neural Circuits ◽  
Central Complex ◽  
Insect Brain ◽  
Neuronal Circuits ◽  
And Function ◽  
Alternative Solutions ◽  
And Robotics

Understanding neuronal circuits that have evolved over millions of years to control adaptive behavior may provide us with alternative solutions to problems in robotics. Recently developed genetic tools allow us to study the connectivity and function of the insect nervous system at the single neuron level. However, neuronal circuits are complex, so the question remains, can we unravel the complex neuronal connectivity to understand the principles of the computations it embodies? Here, I illustrate the plausibility of incorporating reverse engineering to analyze part of the central complex, an insect brain structure essential for navigation behaviors such as maintaining a specific compass heading and path integration. I demonstrate that the combination of reverse engineering with simulations allows the study of both the structure and function of the underlying circuit, an approach that augments our understanding of both the computation performed by the neuronal circuit and the role of its components.

scholarly journals Regulation of sexually dimorphic abdominal courtship behaviors in Drosophila by the Tlx/tailless-like nuclear receptor, Dissatisfaction

2021 ◽  
Author(s):  
Julia C Duckhorn ◽  
Jessica Cande ◽  
Mary C Metkus ◽  
Hyeop Song ◽  
Sofia Altamirano ◽  
...  
Keyword(s):  
Nuclear Receptor ◽  
Sexual Behaviors ◽  
Sexually Dimorphic ◽  
Orphan Nuclear Receptor ◽  
Female Development ◽  
The Central Nervous System ◽  
Courtship Behaviors ◽  
And Function ◽  
Male Specific ◽  
Necessary And Sufficient

Sexually dimorphic courtship behaviors in Drosophila melanogaster develop from the activity of the sexual differentiation genes, doublesex (dsx) and fruitless (fru), functioning with other regulatory factors that have received little attention. The dissatisfaction gene (dsf) encodes an orphan nuclear receptor homologous to vertebrate Tlx and Drosophila tailless that is critical for the development of several aspects of female- and male-specific sexual behaviors. Here, we report the pattern of dsf expression in the central nervous system and show that the activity of sexually dimorphic abdominal interneurons that co-express dsf and dsx is necessary and sufficient for vaginal plate opening in virgin females and abdominal curling in males during courtship. We find that dsf activity results in different neuroanatomical outcomes in females and males, promoting and suppressing, respectively, female development and function of the DDAG neurons depending upon the sexual state of dsx expression. We posit that dsf and dsx interact to specify sex differences in the neural circuitry for dimorphic abdominal behaviors.

scholarly journals Neurons interact with the microbiome: an evolutionary-informed perspective

Neuroforum ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Christoph Giez ◽  
Alexander Klimovich ◽  
Thomas C. G. Bosch
Keyword(s):  
Nervous System ◽  
Neural Circuits ◽  
Current Knowledge ◽  
System Development ◽  
Nervous System Development ◽  
Comprehensive Understanding ◽  
Strategic Model ◽  
Microbe Interactions ◽  
Host Microbe Interactions ◽  
And Function

Abstract Animals have evolved within the framework of microbes and are constantly exposed to diverse microbiota. Microbes colonize most, if not all, animal epithelia and influence the activity of many organs, including the nervous system. Therefore, any consideration on nervous system development and function in the absence of the recognition of microbes will be incomplete. Here, we review the current knowledge on the nervous systems of Hydra and its role in the host–microbiome communication. We show that recent advances in molecular and imaging methods are allowing a comprehensive understanding of the capacity of such a seemingly simple nervous system in the context of the metaorganism. We propose that the development, function and evolution of neural circuits must be considered in the context of host–microbe interactions and present Hydra as a strategic model system with great basic and translational relevance for neuroscience.

scholarly journals Oscillatory integration windows in neurons

2016 ◽  
Author(s):  
Nitin Gupta ◽  
Swikriti Saran Singh ◽  
Mark Stopfer
Keyword(s):  
Neural Circuits ◽  
Neural Circuit ◽  
Field Potential ◽  
Coincidence Detection ◽  
Uniform Structure ◽  
Detection Mechanism ◽  
Oscillation Frequencies ◽  
Local Field Potential Lfp ◽  
Oscillatory Cycle

AbstractOscillatory synchrony among neurons occurs in many species and brain areas, and has been proposed to help neural circuits process information. One hypothesis states that oscillatory input creates cyclic integration windows: specific times in each oscillatory cycle when postsynaptic neurons become especially responsive to inputs. With paired local field potential (LFP) and intracellular recordings and controlled stimulus manipulations we directly tested this idea in the locust olfactory system. We found that inputs arriving in Kenyon cells (KCs) sum most effectively in a preferred window of the oscillation cycle. With a computational model, we found that the non-uniform structure of noise in the membrane potential helps mediate this process. Further experiments performed in vivo demonstrated that integration windows can form in the absence of inhibition and at a broad range of oscillation frequencies. Our results reveal how a fundamental coincidence-detection mechanism in a neural circuit functions to decode temporally organized spiking.

scholarly journals Zebrafish Dscaml1 is Essential for Retinal Patterning and Function of Oculomotor Subcircuits

2019 ◽  
Author(s):  
Manxiu Ma ◽  
Alexandro D. Ramirez ◽  
Tong Wang ◽  
Rachel L. Roberts ◽  
Katherine E. Harmon ◽  
...  
Keyword(s):  
Animal Model ◽  
Light Adaptation ◽  
Neural Circuit ◽  
Oculomotor System ◽  
Gaze Stabilization ◽  
Ocular Disorders ◽  
Motor Apraxia ◽  
Premotor Pathways ◽  
And Function ◽  
Circuit Function

AbstractDown Syndrome Cell Adhesion Molecules (dscam and dscaml1) are essential regulators of neural circuit assembly, but their roles in vertebrate neural circuit function are still mostly unexplored. We investigated the role of dscaml1 in the zebrafish oculomotor system, where behavior, circuit function, and neuronal activity can be precisely quantified. Loss of zebrafish dscaml1 resulted in deficits in retinal patterning and light adaptation, consistent with its known roles in mammals. Oculomotor analyses showed that mutants have abnormal gaze stabilization, impaired fixation, disconjugation, and faster fatigue. Notably, the saccade and fatigue phenotypes in dscaml1 mutants are reminiscent of human ocular motor apraxia, for which no animal model exists. Two-photon calcium imaging showed that loss of dscaml1 leads to impairment in the saccadic premotor pathway but not the pretectum-vestibular premotor pathway, indicating a subcircuit requirement for dscaml1. Together, we show that dscaml1 has both broad and specific roles in oculomotor circuit function, providing a new animal model to investigate the development of premotor pathways and their associated human ocular disorders.

Sign in / Sign up

Export Citation Format

Share Document