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Current Biology : CB Oct 2022The diversity of visual input processed by the mammalian visual system requires the generation of many distinct retinal ganglion cell (RGC) types, each tuned to a...
The diversity of visual input processed by the mammalian visual system requires the generation of many distinct retinal ganglion cell (RGC) types, each tuned to a particular feature. The molecular code needed to generate this cell-type diversity is poorly understood. Here, we focus on the molecules needed to specify one type of retinal cell: the upward-preferring ON direction-selective ganglion cell (up-oDSGC) of the mouse visual system. Single-cell transcriptomic profiling of up- and down-oDSGCs shows that the transcription factor Tbx5 is selectively expressed in up-oDSGCs. The loss of Tbx5 in up-oDSGCs results in a selective defect in the formation of up-oDSGCs and a corresponding inability to detect vertical motion. A downstream effector of Tbx5, Sfrp1, is also critical for vertical motion detection but not up-oDSGC formation. These results advance our understanding of the molecular mechanisms that specify a rare retinal cell type and show how disrupting this specification leads to a corresponding defect in neural circuitry and behavior.
Topics: Animals; Ganglia; Gene Expression Regulation; Mice; Retina; Retinal Ganglion Cells; T-Box Domain Proteins; Transcription Factors
PubMed: 35998637
DOI: 10.1016/j.cub.2022.07.064 -
Viruses Jun 2018Primary varicella-zoster virus (VZV) infection causes varicella (chickenpox) and the establishment of a lifelong latent infection in ganglionic neurons. VZV reactivates... (Review)
Review
Primary varicella-zoster virus (VZV) infection causes varicella (chickenpox) and the establishment of a lifelong latent infection in ganglionic neurons. VZV reactivates in about one-third of infected individuals to cause herpes zoster, often accompanied by neurological complications. The restricted host range of VZV and, until recently, a lack of suitable in vitro models have seriously hampered molecular studies of VZV latency. Nevertheless, recent technological advances facilitated a series of exciting studies that resulted in the discovery of a VZV latency-associated transcript (VLT) and provide novel insights into our understanding of VZV latency and factors that may initiate reactivation. Deducing the function(s) of VLT and the molecular mechanisms involved should now be considered a priority to improve our understanding of factors that govern VZV latency and reactivation. In this review, we summarize the implications of recent discoveries in the VZV latency field from both a virus and host perspective and provide a roadmap for future studies.
Topics: Adaptive Immunity; Animals; Chickenpox; Epigenesis, Genetic; Ganglion Cysts; Gene Expression Regulation, Viral; Genome, Viral; Genomics; Herpesvirus 3, Human; High-Throughput Nucleotide Sequencing; Humans; Immediate-Early Proteins; Immunity, Innate; Neurons; Viral Envelope Proteins; Virus Activation; Virus Latency
PubMed: 29958408
DOI: 10.3390/v10070349 -
Clinical Autonomic Research : Official... Feb 2018We recently defined genetic traits that distinguish sympathetic from parasympathetic neurons, both preganglionic and ganglionic (Espinosa-Medina et al., Science... (Review)
Review
We recently defined genetic traits that distinguish sympathetic from parasympathetic neurons, both preganglionic and ganglionic (Espinosa-Medina et al., Science 354:893-897, 2016). By this set of criteria, we found that the sacral autonomic outflow is sympathetic, not parasympathetic as has been thought for more than a century. Proposing such a belated shift in perspective begs the question why the new criterion (cell types defined by their genetic make-up and dependencies) should be favored over the anatomical, physiological and pharmacological considerations of long ago that inspired the "parasympathetic" classification. After a brief reminder of the former, we expound the weaknesses of the latter and argue that the novel genetic definition helps integrating neglected anatomical and physiological observations and clearing the path for future research.
Topics: Ganglia, Parasympathetic; Ganglia, Sympathetic; Humans; Sacrococcygeal Region; Spinal Cord
PubMed: 29103139
DOI: 10.1007/s10286-017-0478-7 -
The Journal of International Medical... Jul 2019Neurobiology studies are increasingly focused on the dorsal root ganglion (DRG), which plays an important role in neuropathic pain. Existing DRG neuron primary culture...
OBJECTIVE
Neurobiology studies are increasingly focused on the dorsal root ganglion (DRG), which plays an important role in neuropathic pain. Existing DRG neuron primary culture methods have considerable limitations, including challenging cell isolation and poor cell yield, which cause difficulty in signaling pathway studies. The present study aimed to establish an integrated primary culture method for DRG neurons.
METHODS
DRGs were obtained from fetal rats by microdissection, and then dissociated with trypsin. The dissociated neurons were treated with 5-fluorouracil to promote growth of neurons from the isolated cells. Then, reverse transcription polymerase chain reaction and immunofluorescence assays were used to identify and purify DRG neurons.
RESULTS
Isolated DRGs were successfully dissociated and showed robust growth as individual DRG neurons in neurobasal medium. Both mRNA and protein assays confirmed that DRG neurons expressed neurofilament-200 and neuron-specific enolase.
CONCLUSIONS
Highly purified, stable DRG neurons could be easily harvested and grown for extended periods by using this integrated cell isolation and purification method, which may help to elucidate the mechanisms underlying neuropathic pain.
Topics: Animals; Cell Separation; Cells, Cultured; Fetus; Ganglia, Spinal; Neurons; Rats; Rats, Sprague-Dawley
PubMed: 31213102
DOI: 10.1177/0300060519855585 -
Anatomical Record (Hoboken, N.J. : 2007) Dec 2019Although pulmonary ganglia were considered to be an analogue of the myenteric ganglia of intestines in embryos, there seemed to be no morphological evaluation in the...
Although pulmonary ganglia were considered to be an analogue of the myenteric ganglia of intestines in embryos, there seemed to be no morphological evaluation in the later stage of development. We conducted immunostainings of intrapulmonary nerves using 17 human fetuses at 14-18 and 28-34 weeks. The ganglion cells were small (15-20 μm in diameter) in the earlier group, but they increased in size (20-30 μm) in the late group. One ganglion, containing 5-30 cell bodies, was usually located "outside" of the bronchial smooth muscle or cartilage. In addition, a few ganglion was found beneath the mucosa of the trachea and principal bronchi. The highest density of ganglia (5-15 ganglia per section with 50 μm interval) was found at the origin of the subsegmental bronchi, but ganglia were absent along more peripheral bronchi those are responsible for contraction and obstruction of the airway. Therefore, in topographical relation between smooth muscle and nerve, intrapulmonary intrinsic neurons were different from intestinal myenteric neurons. Consequently, a previous hypothesis of "embryonic intramuscular bronchial ganglia" seemed not to be based on observations of the peripheral bronchus but on the central bronchus than the sub-subsegmental level. An extrinsic migration and redistribution of ganglia might occur at midterm to provide the final location outside of airway smooth muscles. Finally, no ganglion cell bodies were positive either for neuronal nitric oxide synthase or tyrosine hydroxylase. Instead of the classical entity of autonomic nerves, nonadrenergic noncholinergic (NANC) innervation might be dominant even in fetuses. Anat Rec, 302:2233-2244, 2019. © 2019 American Association for Anatomy.
Topics: Bronchi; Fetus; Ganglia; Humans; Intestines; Muscle, Smooth; Neurons
PubMed: 31241243
DOI: 10.1002/ar.24208 -
Channels (Austin, Tex.) Dec 2023The Nav1.9 channel is a voltage-gated sodium channel. It plays a vital role in the generation of pain and the formation of neuronal hyperexcitability after inflammation.... (Review)
Review
The Nav1.9 channel is a voltage-gated sodium channel. It plays a vital role in the generation of pain and the formation of neuronal hyperexcitability after inflammation. It is highly expressed in small diameter neurons of dorsal root ganglions and Dogiel II neurons in enteric nervous system. The small diameter neurons in dorsal root ganglions are the primary sensory neurons of pain conduction. Nav1.9 channels also participate in regulating intestinal motility. Functional enhancements of Nav1.9 channels to a certain extent lead to hyperexcitability of small diameter dorsal root ganglion neurons. The hyperexcitability of the neurons can cause visceral hyperalgesia. Intestinofugal afferent neurons and intrinsic primary afferent neurons in enteric nervous system belong to Dogiel type II neurons. Their excitability can also be regulated by Nav1.9 channels. The hyperexcitability of intestinofugal afferent neurons abnormally activate entero-enteric inhibitory reflexes. The hyperexcitability of intrinsic primary afferent neurons disturb peristaltic waves by abnormally activating peristaltic reflexes. This review discusses the role of Nav1.9 channels in intestinal hyperpathia and dysmotility.
Topics: Humans; Ganglia, Spinal; Hyperalgesia; Neurons; Pain; NAV1.9 Voltage-Gated Sodium Channel
PubMed: 37186898
DOI: 10.1080/19336950.2023.2212350 -
Scientific Reports Jun 2018The currently unsurpassed diversity of photoreceptors found in the eyes of stomatopods, or mantis shrimps, is achieved through a variety of opsin-based visual pigments...
The currently unsurpassed diversity of photoreceptors found in the eyes of stomatopods, or mantis shrimps, is achieved through a variety of opsin-based visual pigments and optical filters. However, the presence of extraocular photoreceptors in these crustaceans is undescribed. Opsins have been found in extraocular tissues across animal taxa, but their functions are often unknown. Here, we show that the mantis shrimp Neogonodactylus oerstedii has functional cerebral photoreceptors, which expands the suite of mechanisms by which mantis shrimp sense light. Illumination of extraocular photoreceptors elicits behaviors akin to common arthropod escape responses, which persist in blinded individuals. The anterior central nervous system, which is illuminated when a mantis shrimp's cephalothorax protrudes from its burrow to search for predators, prey, or mates, appears to be photosensitive and to feature two types of opsin-based, potentially histaminergic photoreceptors. A pigmented ventral eye that may be capable of color discrimination extends from the cerebral ganglion, or brain, against the transparent outer carapace, and exhibits a rapid electrical response when illuminated. Additionally, opsins and histamine are expressed in several locations of the eyestalks and cerebral ganglion, where any photoresponses could contribute to shelter-seeking behaviors and other functions.
Topics: Animals; Brain; Decapoda; Ganglion Cysts; Histamine; Opsins; Photoreceptor Cells, Vertebrate
PubMed: 29946145
DOI: 10.1038/s41598-018-28004-w -
Vision Research Mar 1996This review summarizes recent work relevant to receptive field structure of cells of the parvocellular (PC) and (MC) magnocellular pathways in the primate. In the... (Review)
Review
This review summarizes recent work relevant to receptive field structure of cells of the parvocellular (PC) and (MC) magnocellular pathways in the primate. In the PC-pathway, recent data suggest that different color- and cone-opponent ganglion cells make up specific anatomical classes with specific cone connectivities and bipolar cell input. For example, blue-on ganglion cells have been identified anatomically as the small bistratified ganglion cell class. For the midget ganglion cells, which appear to be red-green opponent, there seems to be only one mosaic for red and green on-center and one for red and green off-center cells. This mixture of cell type within a retinal cell mosaic is unusual, as is the fact that dendritic trees of neighboring midget cells do not overlap. Physiologically, all PC-cells lack a contrast gain control mechanism and show a high degree of spatial and temporal linearity of their responses. In the magnocellular pathway, on- and off-center cells, corresponding to parasol cells with dendritic trees ramifying in the inner and outer sublaminae of the inner plexiform layer, show properties familiar from studies of cat ganglion cells, e.g. a contrast gain control is present. However, a chromatic input to the receptive field surround gives their responses an additional order of complexity.
Topics: Animals; Ganglia; Primates; Retina; Visual Perception
PubMed: 8762295
DOI: 10.1016/0042-6989(95)00167-0 -
The Journal of Comparative Neurology Jan 2021While autonomic ganglia have been extensively studied in rats instead of mice, there is renewed interest in the anatomy of the mouse autonomic nervous system. This study...
While autonomic ganglia have been extensively studied in rats instead of mice, there is renewed interest in the anatomy of the mouse autonomic nervous system. This study examined the prevalence and anatomical features of a cell bridge linking two autonomic ganglia of the neck, namely, the nodose ganglion (NG) and the superior cervical ganglion (SCG) in a cohort of C57BL/6J mice. We identified a cell bridge between the NG and the cranial pole of the SCG. This cell bridge was tubular shaped with an average length and width of 700 and 240 μm, respectively. The cell bridge was frequently unilateral and significantly more prevalent in the ganglionic masses from males (38%) than females (21%). On each of its extremities, it contained a mixed of vagal afferents and postganglionic sympathetic neurons. The two populations of neurons abruptly replaced each other in the middle of the cell bridge. We examined the mRNA expression for selected autonomic markers in samples of the NG with or without cell bridge. Our results indicated that the cell bridge was enriched in both markers of postganglionic sympathetic and vagal afferents neurons. Lastly, using FluoroGold microinjection into the NG, we found that the existence of a cell bridge may occasionally lead to the inadvertent contamination of the SCG. In summary, this study describes the anatomy of a cell bridge variant consisting of the fusion of the mouse NG and SCG. The practical implications of our observations are discussed with respect to studies of the mouse vagal afferents, an area of research of increasing popularity.
Topics: Animals; Female; Male; Mice; Mice, Inbred C57BL; Nodose Ganglion; Prevalence; Superior Cervical Ganglion
PubMed: 32356570
DOI: 10.1002/cne.24936 -
European Journal of Histochemistry : EJH Jun 2021The neuroglia of the central and peripheral nervous systems undergo numerous changes during normal aging. Astrocytes become hypertrophic and accumulate intermediate... (Review)
Review
The neuroglia of the central and peripheral nervous systems undergo numerous changes during normal aging. Astrocytes become hypertrophic and accumulate intermediate filaments. Oligodendrocytes and Schwann cells undergo alterations that are often accompanied by degenerative changes to the myelin sheath. In microglia, proliferation in response to injury, motility of cell processes, ability to migrate to sites of neural injury, and phagocytic and autophagic capabilities are reduced. In sensory ganglia, the number and extent of gaps between perineuronal satellite cells - that leave the surfaces of sensory ganglion neurons directly exposed to basal lamina- increase significantly. The molecular profiles of neuroglia also change in old age, which, in view of the interactions between neurons and neuroglia, have negative consequences for important physiological processes in the nervous system. Since neuroglia actively participate in numerous nervous system processes, it is likely that not only neurons but also neuroglia will prove to be useful targets for interventions to prevent, reverse or slow the behavioral changes and cognitive decline that often accompany senescence.
Topics: Aging; Animals; Astrocytes; Ganglia; Neuroglia; Schwann Cells; Sensory Receptor Cells
PubMed: 34346664
DOI: 10.4081/ejh.2021.3249