scholarly journals The pericardium of Oikopleura dioica (Tunicata, Appendicularia) contains two distinct cell types and is rotated by 90 degrees to the left

Zoomorphology ◽  
2021 ◽  
Author(s):  
Mai-Lee Van Le ◽  
Maria Novosolov ◽  
Dorothee Huchon ◽  
Thomas Stach
Keyword(s):  
Basal Lamina ◽  
Cell Types ◽  
Body Cavity ◽  
The Body ◽  
Last Common Ancestor ◽  
Myocardial Cells ◽  
Oikopleura Dioica ◽  
Peritoneal Cells ◽  
Distinct Cell ◽  
Primary Body

AbstractThe planktonic Oikopleura dioica belongs to Tunicata, the probable sister taxon to Craniota, and might show plesiomorphic characters, conserved from the common lineage of Tunicata and Craniota. In O. dioica a pericardium in a position similar to other chordates but also to the heart and pericardium of craniates is found. Surprisingly, little is known about the ultrastructure of the pericardium in O. dioica. Here, we show based on electron microscopy that the pericardium is completely lined by a single layer of 16 epithelial cells: 6 epithelial myocardial cells on the left side of the pericardium and 10 peritoneal cells constituting the right side. One of the peritoneal cells, situated at the ventral border between peritoneal cells and myocardial cells has an extension that anchors the pericardium to the basal lamina beneath the latero-ventral epidermis. The primary body cavity of O. dioica appears quite uniformly clear in electron microscopic aspect but several sheets, resembling the basal lamina of the pericardium cross the larger spaces of the body cavity and connect to the pericardial basal lamina. This is the first detailed description of two distinct cell types in the epithelial lining of the pericardium of O. dioica. In comparison with other chordates, we conclude that two cell types can be reconstructed for the last common ancestor of Chordata at least. The position of the pericardium at the intersection of trunk and tail in combination with the basal-lamina like sheets spanning the hemocoel is probably of importance for the function of the circulation of the hemocoelic fluid. Similar to the tail, the axis of the pericardium is shifted through 90 degrees to the left as compared to the main body axis of the trunk and we infer that this shift is an apomorphic character of Appendicularia.

scholarly journals Glucocorticoid Receptor β (GRβ): Beyond Its Dominant-Negative Function

2021 ◽  
Vol 22 (7) ◽  
pp. 3649
Author(s):  
Patricia Ramos-Ramírez ◽  
Omar Tliba
Keyword(s):  
Current Knowledge ◽  
Inflammatory Diseases ◽  
Cell Communication ◽  
Cell Types ◽  
The Body ◽  
Dominant Negative ◽  
Negative Effects ◽  
Independent Manner ◽  
Distinct Cell ◽  
Induced Apoptosis

Glucocorticoids (GCs) act via the GC receptor (GR), a receptor ubiquitously expressed in the body where it drives a broad spectrum of responses within distinct cell types and tissues, which vary in strength and specificity. The variability of GR-mediated cell responses is further extended by the existence of GR isoforms, such as GRα and GRβ, generated through alternative splicing mechanisms. While GRα is the classic receptor responsible for GC actions, GRβ has been implicated in the impairment of GRα-mediated activities. Interestingly, in contrast to the popular belief that GRβ actions are restricted to its dominant-negative effects on GRα-mediated responses, GRβ has been shown to have intrinsic activities and “directly” regulates a plethora of genes related to inflammatory process, cell communication, migration, and malignancy, each in a GRα-independent manner. Furthermore, GRβ has been associated with increased cell migration, growth, and reduced sensitivity to GC-induced apoptosis. We will summarize the current knowledge of GRβ-mediated responses, with a focus on the GRα-independent/intrinsic effects of GRβ and the associated non-canonical signaling pathways. Where appropriate, potential links to airway inflammatory diseases will be highlighted.

Determination and transdetermination in imaginal disks of Drosophila (Summary only)

1970 ◽  
Vol 176 (1044) ◽  
pp. 291-293
Keyword(s):  
Single Cells ◽  
Body Part ◽  
Cell Types ◽  
Structural Features ◽  
Theoretical Concept ◽  
Body Cavity ◽  
The Body ◽  
Body Region ◽  
Body Parts ◽  
Imaginal Disks

It is generally assumed that in multicellular organisms the diversity of the different cell types is the result of different gene activity which becomes manifest in the course of development. This theoretical concept of cell differentiation was developed on the basis of results obtained from a relatively small number of suitable experimental systems. One of them comprises the imaginal disks of the fruitfly Drosophila melanogaster . Imaginal disks are larval primordia in holometabolic insects such as flies and mosquitoes, and consist of densely packed populations of morphologically uniform cells. They give rise to defined structures of the adult body (mainly integument), thus replacing parts of the larva which are almost completely histolysed during metamorphosis. The prospective fate of the various imaginal disks can be tested, for example, by transplantation experiments. Individual disks are removed from larvae of a genetically marked strain and transplanted into the body cavity of another larva with which the transplants undergo metamorphosis. The metamorphosed derivatives of the disks are then found in the abdomen of the fly and can be microscopically identified on the basis of the morphology of bristles, hairs and other structural features of the integument. The same method is applied for examination of the developmental performance of disk fragments. From the results of such experiments the following conclusions are drawn: (1) Individual disks of fully grown larvae, that is larvae which are ready to pupate, are determined (programmed) for exactly defined body parts of the adult organism. (2) The individual subregions of such a body part can be localized precisely within a disk. Based on these facts fate maps (anlage plans) can be worked out. (3) From experiments in which different genetically marked disks are intermingled and then transplanted into larvae it is concluded that even single cells are determined for structures of a specific body region.

scholarly journals Responses and coping methods of different testicular cell types to heat stress: overview and perspectives

2021 ◽  
Author(s):  
Hui Cai ◽  
Dezhe Qin ◽  
Sha Peng
Keyword(s):  
Heat Stress ◽  
Leydig Cells ◽  
Cell Types ◽  
Cellular Responses ◽  
Body Cavity ◽  
The Body ◽  
Testicular Cell ◽  
Coping Methods ◽  
And Coping ◽  
Different Cell Types

To facilitate temperature adjustments, the testicles are located outside the body cavity. In most mammals, the temperature of the testes is lower than the body temperature to ensure the normal progression of spermatogenesis. Rising temperatures affect spermatogenesis and eventually lead to a decline in male fertility or even infertility. However, the testes are composed of different cell types, including spermatogonial stem cells, spermatocytes, spermatozoa, Leydig cells, and Sertoli cells, which have different cellular responses to heat stress. Recent studies have shown that using different drugs can relieve heat-stress-induced reproductive damage by regulating different signaling pathways. Here, we review the mechanisms by which heat stress damages different cells in testes and possible treatments.

Comparison of early nerve cord development in insects and vertebrates

Development ◽  
1999 ◽  
Vol 126 (11) ◽  
pp. 2309-2325 ◽  
Author(s):  
D. Arendt ◽  
K. Nubler-Jung
Keyword(s):  
Neural Progenitor Cells ◽  
Regional Distribution ◽  
Cell Types ◽  
Molecular Data ◽  
Body Cavity ◽  
The Body ◽  
Lateral Nerve ◽  
Nerve Roots ◽  
Commissural Axons ◽  
Lateral Column

It is widely held that the insect and vertebrate CNS evolved independently. This view is now challenged by the concept of dorsoventral axis inversion, which holds that ventral in insects corresponds to dorsal in vertebrates. Here, insect and vertebrate CNS development is compared involving embryological and molecular data. In insects and vertebrates, neurons differentiate towards the body cavity. At early stages of neurogenesis, neural progenitor cells are arranged in three longitudinal columns on either side of the midline, and NK-2/NK-2.2, ind/Gsh and msh/Msx homologs specify the medial, intermediate and lateral columns, respectively. Other pairs of regional specification genes are, however, expressed in transverse stripes in insects, and in longitudinal stripes in the vertebrates. There are differences in the regional distribution of cell types in the developing neuroectoderm. However, within a given neurogenic column in insects and vertebrates some of the emerging cell types are remarkably similar and may thus be phylogenetically old: NK-2/NK-2.2-expressing medial column neuroblasts give rise to interneurons that pioneer the medial longitudinal fascicles, and to motoneurons that exit via lateral nerve roots to then project peripherally. Lateral column neuroblasts produce, among other cell types, nerve root glia and peripheral glia. Midline precursors give rise to glial cells that enwrap outgrowing commissural axons. The midline glia also express netrin homologs to attract commissural axons from a distance.

scholarly journals High-resolution transcriptional and morphogenetic profiling of cells from micropatterned human ESC gastruloid cultures

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Kyaw Thu Minn ◽  
Yuheng C Fu ◽  
Shenghua He ◽  
Sabine Dietmann ◽  
Steven C George ◽  
...  
Keyword(s):  
Single Cells ◽  
Primordial Germ Cells ◽  
Embryonic Stem ◽  
Cell Types ◽  
The Body ◽  
Human Embryos ◽  
Germ Layers ◽  
Distinct Cell ◽  
Evolutionarily Conserved ◽  
Species Comparisons

During mammalian gastrulation, germ layers arise and are shaped into the body plan while extraembryonic layers sustain the embryo. Human embryonic stem cells, cultured with BMP4 on extracellular matrix micro-discs, reproducibly differentiate into gastruloids, expressing markers of germ layers and extraembryonic cells in radial arrangement. Using single-cell RNA sequencing and cross-species comparisons with mouse, cynomolgus monkey gastrulae, and post-implantation human embryos, we reveal that gastruloids contain cells transcriptionally similar to epiblast, ectoderm, mesoderm, endoderm, primordial germ cells, trophectoderm, and amnion. Upon gastruloid dissociation, single cells reseeded onto micro-discs were motile and aggregated with the same but segregated from distinct cell types. Ectodermal cells segregated from endodermal and extraembryonic but mixed with mesodermal cells. Our work demonstrates that the gastruloid system models primate-specific features of embryogenesis, and that gastruloid cells exhibit evolutionarily conserved sorting behaviors. This work generates a resource for transcriptomes of human extraembryonic and embryonic germ layers differentiated in a stereotyped arrangement.

scholarly journals Characterization of Individual Projections Reveal That Neuromasts of the Zebrafish Lateral Line are Innervated by Multiple Inhibitory Efferent Cells

2021 ◽  
Vol 15 ◽  
Author(s):  
Remy Manuel ◽  
Ana Belen Iglesias Gonzalez ◽  
Judith Habicher ◽  
Harmen Kornelis Koning ◽  
Henrik Boije
Keyword(s):  
Lateral Line ◽  
Sensory System ◽  
Time Lapse ◽  
Cell Types ◽  
The Body ◽  
Posterior Lateral Line ◽  
Distinct Cell ◽  
Efferent Neurons ◽  
Time Lapse Imaging

The zebrafish lateral line is a sensory system used to detect changes in water flow. It is comprized of clusters of superficial hair cells called neuromasts. Modulation occurs via excitatory and inhibitory efferent neurons located in the brain. Using mosaic transgenic labeling we provide an anatomical overview of the lateral line projections made by individual inhibitory efferent neurons in 5-day old zebrafish larvae. For each hemisphere we estimate there to be six inhibitory efferent neurons located in two different nuclei. Three distinct cell types were classified based on their projections; to the anterior lateral line around the head, to the posterior lateral line along the body, or to both. Our analyses corroborate previous studies employing back-fills, but our transgenic labeling allowed a more thorough characterization of their morphology. We found that individual inhibitory efferent cells connect to multiple neuromasts and that a single neuromast is connected by multiple inhibitory efferent cells. The efferent axons project to the sensory ganglia and follow the sensory axon tract along the lateral line. Time-lapse imaging revealed that inhibitory efferent axons do not migrate with the primordium as the primary sensory afferent does, but follow with an 8–14 h lag. These data bring new insights into the formation of a sensory circuit and support the hypothesis that different classes of inhibitory efferent cells have different functions. Our findings provide a foundation for future studies focussed toward unraveling how and when sensory perception is modulated by different efferent cells.

scholarly journals High-resolution transcriptional and morphogenetic profiling of cells from micropatterned human embryonic stem cell gastruloid cultures

2020 ◽  
Author(s):  
Kyaw Thu Minn ◽  
Yuheng C. Fu ◽  
Shenghua He ◽  
Steven C. George ◽  
Mark A. Anastasio ◽  
...  
Keyword(s):  
Human Embryonic Stem Cell ◽  
Single Cells ◽  
Embryonic Stem ◽  
Cell Types ◽  
The Body ◽  
Germ Layers ◽  
Distinct Cell ◽  
Evolutionarily Conserved ◽  
Species Comparisons ◽  
Radial Organization

SummaryDuring mammalian gastrulation, germ layers arise and are shaped into the body plan while extraembryonic layers sustain the embryo. Human embryonic stem cells, cultured with BMP4 on extracellular matrix micro-discs, reproducibly differentiate into gastruloids, expressing markers of germ layers and extraembryonic cells with radial organization. Single-cell RNA sequencing and cross-species comparisons with mouse and cynomolgus monkey gastrulae suggest that gastruloids contain seven major cell types, including epiblast, ectoderm, mesoderm, endoderm, and extraembryonic trophoblast- and amnion-like cells. Upon gastruloid dissociation, single cells reseeded onto micro-discs were motile and aggregated with the same but segregated from distinct cell types. Ectodermal cells segregated from endodermal and extraembryonic cells but mixed with mesodermal cells. Our work demonstrates that the gastruloid system supports primate-specific features of embryogenesis, and that gastruloid cells exhibit evolutionarily conserved sorting behaviors. This work generates a resource for transcriptomes of human extraembryonic and embryonic germ layers differentiated in a stereotyped arrangement.

Fine Structure of the Malpighian Tubules of the Mosquito, Culex pipiens

1971 ◽  
Vol 29 ◽  
pp. 402-403
Author(s):  
Brendan Clifford
Keyword(s):  
Fine Structure ◽  
Culex Pipiens ◽  
Stellate Cell ◽  
Malpighian Tubule ◽  
Cell Types ◽  
Instar Larva ◽  
Malpighian Tubules ◽  
Calliphora Erythrocephala ◽  
Distinct Cell ◽  
Basal Plasma

An ultrastructural investigation of the Malpighian tubules of the fourth instar larva of Culex pipiens was undertaken as part of a continuing study of the fine structure of transport epithelia.Each of the five Malpighian tubules was found to be morphologically identical and regionally undifferentiated. Two distinct cell types, the primary and stellate, were found intermingled along the length of each tubule. The ultrastructure of the stellate cell was previously described in the Malpighian tubule of the blowfly, Calliphora erythrocephala by Berridge and Oschman.The basal plasma membrane of the primary cell is extremely irregular, giving rise to a complex interconnecting network of basal channels. The compartments of cytoplasm entrapped within this system of basal infoldings contain mitochondria, free ribosomes, and small amounts of rough endoplasmic reticulum. The mitochondria are distinctive in that the cristae run parallel to the long axis of the organelle.

scholarly journals Extracellular-Vesicle-Based Coatings Enhance Bioactivity of Titanium Implants—SurfEV

Nanomaterials ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1445
Author(s):  
Taisa Nogueira Pansani ◽  
Thanh Huyen Phan ◽  
Qingyu Lei ◽  
Alexey Kondyurin ◽  
Bill Kalionis ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Titanium Surface ◽  
Wound Closure ◽  
Cell Types ◽  
Extracellular Vesicle ◽  
Tissue Growth ◽  
Titanium Implants ◽  
The Body ◽  
High Concentrations ◽  
And Migration

Extracellular vesicles (EVs) are nanoparticles released by cells that contain a multitude of biomolecules, which act synergistically to signal multiple cell types. EVs are ideal candidates for promoting tissue growth and regeneration. The tissue regenerative potential of EVs raises the tantalizing possibility that immobilizing EVs on implant surfaces could potentially generate highly bioactive and cell-instructive surfaces that would enhance implant integration into the body. Such surfaces could address a critical limitation of current implants, which do not promote bone tissue formation or bond bone. Here, we developed bioactive titanium surface coatings (SurfEV) using two types of EVs: secreted by decidual mesenchymal stem cells (DEVs) and isolated from fermented papaya fluid (PEVs). For each EV type, we determined the size, morphology, and molecular composition. High concentrations of DEVs enhanced cell proliferation, wound closure, and migration distance of osteoblasts. In contrast, the cell proliferation and wound closure decreased with increasing concentration of PEVs. DEVs enhanced Ca/P deposition on the titanium surface, which suggests improvement in bone bonding ability of the implant (i.e., osteointegration). EVs also increased production of Ca and P by osteoblasts and promoted the deposition of mineral phase, which suggests EVs play key roles in cell mineralization. We also found that DEVs stimulated the secretion of secondary EVs observed by the presence of protruding structures on the cell membrane. We concluded that, by functionalizing implant surfaces with specialized EVs, we will be able to enhance implant osteointegration by improving hydroxyapatite formation directly at the surface and potentially circumvent aseptic loosening of implants.

scholarly journals NF-κB in Cancer Immunity: Friend or Foe?

Cells ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 355
Author(s):  
Guilhem Lalle ◽  
Julie Twardowski ◽  
Yenkel Grinberg-Bleyer
Keyword(s):  
Immune Responses ◽  
Therapeutic Potential ◽  
Cell Types ◽  
Transcriptional Activators ◽  
New Class ◽  
Complex Interactions ◽  
Cancer Immunity ◽  
Distinct Cell ◽  
Cancer Initiation ◽  
Cancer Outcome

The emergence of immunotherapies has definitely proven the tight relationship between malignant and immune cells, its impact on cancer outcome and its therapeutic potential. In this context, it is undoubtedly critical to decipher the transcriptional regulation of these complex interactions. Following early observations demonstrating the roles of NF-κB in cancer initiation and progression, a series of studies converge to establish NF-κB as a master regulator of immune responses to cancer. Importantly, NF-κB is a family of transcriptional activators and repressors that can act at different stages of cancer immunity. In this review, we provide an overview of the selective cell-intrinsic contributions of NF-κB to the distinct cell types that compose the tumor immune environment. We also propose a new view of NF-κB targeting drugs as a new class of immunotherapies for cancer.

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