Olfactory Projection Neurons From the Moth Antennal Lobe Lateral Cluster exhibit Diverse Morphological and Neurophysiological Characteristics

Mapping Intimacies ◽

10.1101/274506 ◽

2018 ◽

Cited By ~ 1

Author(s):

Seong-Gyu Lee ◽

Christine Fogarty Celestino ◽

Jeffrey Stagg ◽

Christoph Kleineidam ◽

Neil J. Vickers

Keyword(s):

Antennal Lobe ◽

Cell Cluster ◽

Morphological Properties ◽

Projection Neurons ◽

Physiological Characterization ◽

Lobe Latéral ◽

Excitatory Projection ◽

Dendritic Arbors

AbstractOlfactory projection neurons convey information from the insect antennal lobe (AL) to higher centers in the brain. Many studies on moths have reported excitatory projection neurons with cell bodies in the medial cell cluster (mcPNs) that predominantly send an axon from the AL to calyces of the mushroom body (CA) via the medial antennal lobe tract (mALT) and then to the lateral horn (LH) of the protocerebrum. These neurons tend to have dendritic arbors restricted to a single glomerulus (i.e. they are uniglomerular). In this study, we report on the physiological and morphological properties of a group of pheromone-responsive olfactory projection neurons with cell bodies in the moth AL lateral cell cluster (lcPNs) of two heliothine moth species. While mcPNs typically exhibit a narrow odor tuning range related to the restriction of their dendritic arbors within a single glomerulus, lcPNs exhibited an array of morphological and physiological configurations. Pheromone-responsive lcPNs varied in their associations with glomeruli (uniglomerular and multiglomerular), dendritic arborization structure and connections to higher brain centers with projections primarily through the lateral antennal lobe tract and to a lesser extent the mediolateral antennal lobe tract to a variety of protocerebral targets including ventrolateral and superior neuropils as well as LH. Physiological characterization of lcPNs also revealed a diversity of response profiles including those either enhanced by or reliant upon presentation of a pheromone blend. These responses manifested themselves as higher maximum firing rates and/or improved temporal resolution of pulsatile stimuli. lcPNs therefore participate in conveying a variety of olfactory information relating to qualitative and temporal facets of the pheromone stimulus to a more expansive number of protocerebral targets than their mcPN counterparts. The role of lcPNs in the overall scheme of olfactory processing is discussed.

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Moth pheromone‐selective projection neurons with cell bodies in the antennal lobe lateral cluster exhibit diverse morphological and neurophysiological characteristics

The Journal of Comparative Neurology ◽

10.1002/cne.24611 ◽

2019 ◽

Vol 527 (9) ◽

pp. 1443-1460 ◽

Cited By ~ 4

Author(s):

Seong‐Gyu Lee ◽

Christine Fogarty Celestino ◽

Jeffrey Stagg ◽

Christoph Kleineidam ◽

Neil J. Vickers

Keyword(s):

Antennal Lobe ◽

Projection Neurons ◽

Lobe Latéral

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Physiological and Morphological Characterization of Local Interneurons in the Drosophila Antennal Lobe

Journal of Neurophysiology ◽

10.1152/jn.00249.2010 ◽

2010 ◽

Vol 104 (2) ◽

pp. 1007-1019 ◽

Cited By ~ 80

Author(s):

Yoichi Seki ◽

Jürgen Rybak ◽

Dieter Wicher ◽

Silke Sachse ◽

Bill S. Hansson

Keyword(s):

Antennal Lobe ◽

Neural Circuit ◽

Three Dimensional ◽

Morphological Characterization ◽

Morphological Properties ◽

Electrophysiological Properties ◽

Local Interneurons ◽

Enhancer Trap Line ◽

Almost All

The Drosophila antennal lobe (AL) has become an excellent model for studying early olfactory processing mechanisms. Local interneurons (LNs) connect a large number of glomeruli and are ideally positioned to increase computational capabilities of odor information processing in the AL. Although the neural circuit of the Drosophila AL has been intensively studied at both the input and the output level, the internal circuit is not yet well understood. An unambiguous characterization of LNs is essential to remedy this lack of knowledge. We used whole cell patch-clamp recordings and characterized four classes of LNs in detail using electrophysiological and morphological properties at the single neuron level. Each class of LN displayed unique characteristics in intrinsic electrophysiological properties, showing differences in firing patterns, degree of spike adaptation, and amplitude of spike afterhyperpolarization. Notably, one class of LNs had characteristic burst firing properties, whereas the others were tonically active. Morphologically, neurons from three classes innervated almost all glomeruli, while LNs from one class innervated a specific subpopulation of glomeruli. Three-dimensional reconstruction analyses revealed general characteristics of LN morphology and further differences in dendritic density and distribution within specific glomeruli between the different classes of LNs. Additionally, we found that LNs labeled by a specific enhancer trap line (GAL4-Krasavietz), which had previously been reported as cholinergic LNs, were mostly GABAergic. The current study provides a systematic characterization of olfactory LNs in Drosophila and demonstrates that a variety of inhibitory LNs, characterized by class-specific electrophysiological and morphological properties, construct the neural circuit of the AL.

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Rheological, Mechanical and Morphological Characterization of Fillers in the Nautical Field: The Role of Dispersing Agents on Composite Materials

Polymers ◽

10.3390/polym12061339 ◽

2020 ◽

Vol 12 (6) ◽

pp. 1339 ◽

Cited By ~ 2

Author(s):

Silvia Vita ◽

Rico Ricotti ◽

Andrea Dodero ◽

Silvia Vicini ◽

Per Borchardt ◽

...

Keyword(s):

External Surface ◽

Morphological Characterization ◽

Point Of View ◽

Morphological Properties ◽

Filler Materials ◽

Efficient Tool ◽

Hollow Glass Microspheres ◽

Dispersing Agents

Coatings have a fundamental role in covering the external surface of yachts by acting both as protective and aesthetic layers. In particular, fillers represent the essential layer from the point of view of mechanical properties and consist of a polymeric matrix, different extenders and additives, and dispersing agents, with the latter having the role to provide good extender-matrix compatibility. In the present work, the effects of dispersing agents with an ionic or steric action on the interactions between hollow glass microspheres and an epoxy-polyamide resin are evaluated. Un-crosslinked filler materials are studied via rheological tests, whereas the mechanical and morphological properties of the crosslinked samples are assessed. The results clearly indicate that steric dispersing agents provide a much greater compatibility effect compared to ionic ones, owing to their steric hindrance capability, thus leading to better-performing filler materials with a less-marked Payne effect, which is here proved to be an efficient tool to provide information concerning the extent of component interactions in nautical fillers. To the best of our knowledge, this work represents the first attempt to deeply understand the role of dispersing agents, which are until now empirically used in the preparation of fillers.

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Formaldehyde-Detoxifying Role of theTetrahydromethanopterin-Linked Pathway in MethylobacteriumextorquensAM1

Journal of Bacteriology ◽

10.1128/jb.185.23.7160-7168.2003 ◽

2003 ◽

Vol 185 (24) ◽

pp. 7160-7168 ◽

Cited By ~ 69

Author(s):

Christopher J. Marx ◽

Ludmila Chistoserdova ◽

Mary E. Lidstrom

Keyword(s):

Methylobacterium Extorquens ◽

Physiological Characterization ◽

Facultative Methylotroph ◽

Formaldehyde Oxidation ◽

Detoxification Pathway ◽

Null Mutants

ABSTRACT The facultative methylotroph Methylobacterium extorquens AM1 possesses two pterin-dependent pathways for C1 transfer between formaldehyde and formate, the tetrahydrofolate (H4F)-linked pathway and the tetrahydromethanopterin (H4MPT)-linked pathway. Both pathways are required for growth on C1 substrates; however, mutants defective for the H4MPT pathway reveal a unique phenotype of being inhibited by methanol during growth on multicarbon compounds such as succinate. It has been previously proposed that this methanol-sensitive phenotype is due to the inability to effectively detoxify formaldehyde produced from methanol. Here we present a comparative physiological characterization of four mutants defective in the H4MPT pathway and place them into three different phenotypic classes that are concordant with the biochemical roles of the respective enzymes. We demonstrate that the analogous H4F pathway present in M. extorquens AM1 cannot fulfill the formaldehyde detoxification function, while a heterologously expressed pathway linked to glutathione and NAD+ can successfully substitute for the H4MPT pathway. Additionally, null mutants were generated in genes previously thought to be essential, indicating that the H4MPT pathway is not absolutely required during growth on multicarbon compounds. These results define the role of the H4MPT pathway as the primary formaldehyde oxidation and detoxification pathway in M. extorquens AM1.

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An essay on individual self-determination

Journal of Human Growth and Development ◽

10.7322/jhgd.v29.9412 ◽

2019 ◽

Vol 29 (2) ◽

pp. 131-135

Author(s):

Margarete Afonso ◽

Ernane Pedro Matos Barros ◽

Matheus Paiva Emidio Cavalcanti ◽

Mariane Albuquerque Lima Ribeiro

Keyword(s):

Scientific Field ◽

Point Of View ◽

Self Determination ◽

Sex And Gender ◽

Physiological Characterization ◽

The Social ◽

And Gender ◽

Individual Self

There are several understandings about the role of human gender identity in the scientific field, this discussion correlates definitions of both social and biological basis. The current confusion in the conceptualization of “sex” and “gender” demonstrates the need for a comparative analysis of the scientific dynamic vocabulary, as well as the insertion of an interdisciplinary historical, social and cultural point of view together with the biological view outside the normative binary logic. The word “gender” can be defined as the social construction of sex, differing from the variable “sex” because it refers to a biological dimension of the anatomo-physiological characterization of humans, recognized as essential and innate in determining the distinctions between male and female. Therefore, the JHGD presents a thematic diversity that focuses on issues related to public health, demonstrating the need to develop knowledge to generate impact on public policy strategies, aiming at universality, equity and comprehensiveness in scientific research involving sexand gender and their impacts on health sciences.

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Oscillatory Synchronization Requires Precise and Balanced Feedback Inhibition in a Model of the Insect Antennal Lobe

Neural Computation ◽

10.1162/089976605774320566 ◽

2005 ◽

Vol 17 (12) ◽

pp. 2548-2570 ◽

Cited By ~ 13

Author(s):

Dominique Martinez

Keyword(s):

Antennal Lobe ◽

Feedback Inhibition ◽

Phase Locking ◽

Sensory Information ◽

Field Potential ◽

Low Complexity ◽

Projection Neurons ◽

Synchronization Pattern ◽

Oscillatory Cycle

In the insect olfactory system, odor-evoked transient synchronization of antennal lobe (AL) projection neurons (PNs) is phase-locked to the oscillations of the local field potential. Sensory information is contained in the spatiotemporal synchronization pattern formed by the identities of the phase-locked PNs. This article investigates the role of feedback inhibition from the local neurons (LNs) in this coding. First, experimental biological results are reproduced with a reduced computational spiking neural network model of the AL. Second, the low complexity of the model leads to a mathematical analysis from which a lower bound on the phase-locking probability is derived. Parameters involved in the bound indicate that PN phase locking depends not only on the number of LN-evoked inhibitory postsynaptic potentials (IPSPs) previously received, but also on their temporal jitter. If the inhibition received by a PN at the current oscillatory cycle is both perfectly balanced (i.e., equal to the mean inhibitory drive) and precise (without any jitter), then the PN will be phase-locked at the next oscillatory cycle with probability one.

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Temporally specific engagement of distinct neuronal circuits regulating olfactory habituation in Drosophila

eLife ◽

10.7554/elife.39569 ◽

2018 ◽

Vol 7 ◽

Cited By ~ 4

Author(s):

Ourania Semelidou ◽

Summer F Acevedo ◽

Efthimios MC Skoulakis

Keyword(s):

Antennal Lobe ◽

Molecular Mechanisms ◽

Editorial Note ◽

Mushroom Bodies ◽

Odor Stimulus ◽

Projection Neurons ◽

Editorial Process ◽

Neuronal Circuits ◽

Excitatory Projection ◽

Perceptual Changes

Habituation is the process that enables salience filtering, precipitating perceptual changes that alter the value of environmental stimuli. To discern the neuronal circuits underlying habituation to brief inconsequential stimuli, we developed a novel olfactory habituation paradigm, identifying two distinct phases of the response that engage distinct neuronal circuits. Responsiveness to the continuous odor stimulus is maintained initially, a phase we term habituation latency and requires Rutabaga Adenylyl-Cyclase-depended neurotransmission from GABAergic Antennal Lobe Interneurons and activation of excitatory Projection Neurons (PNs) and the Mushroom Bodies. In contrast, habituation depends on the inhibitory PNs of the middle Antenno-Cerebral Track, requires inner Antenno-Cerebral Track PN activation and defines a temporally distinct phase. Collectively, our data support the involvement of Lateral Horn excitatory and inhibitory stimulation in habituation. These results provide essential cellular substrates for future analyses of the molecular mechanisms that govern the duration and transition between these distinct temporal habituation phases.Editorial note: This article has been through an editorial process in which the authors decide how to respond to the issues raised during peer review. The Reviewing Editor's assessment is that all the issues have been addressed (<xref ref-type="decision-letter" rid="SA1">see decision letter</xref>).

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