scholarly journals Mitochondria-Rich Cells: A Novel Type of Concealed Cell in the Small Intestine of Chinese Soft-Shelled Turtles (Pelodiscus Sinensis)

Animals ◽  
2019 ◽  
Vol 9 (10) ◽  
pp. 717
Author(s):  
Waseem Ali Vistro ◽  
Yifei Liu ◽  
Mengdi Xu ◽  
Ping Yang ◽  
Abdul Haseeb ◽  
...  
Keyword(s):  
Small Intestine ◽  
Ion Transport ◽  
Transport Proteins ◽  
Mucosal Surface ◽  
Apical Region ◽  
Basal Region ◽  
Pelodiscus Sinensis ◽  
Transmission Electron ◽  
Tubular System ◽  
Positive Immunoreactivity

Although some studies have been conducted over the past few decades, the existence of mitochondria-rich cells (MRCs) in reptiles is still obscure. This is the first study to uncover the presence of MRCs in the small intestine of Chinese soft-shelled turtles. In this study, we investigated the ultrastructural characteristics of MRCs and the secretion of different ion transport proteins in the small intestine of Pelodiscus sinensis. Transmission electron microscopy revealed that the ultrastructural features of MRCs are clearly different from those of other cells. The cytoplasmic density of MRCs was higher than absorptive epithelial cells (AECs) and goblet cells (GCs). MRCs possessed abundant heterogeneous mitochondria and an extensive tubular system in the cytoplasm, however, the AECs and GCs completely lacked a tubular system. Statistical analysis showed that the diameter and quantification of mitochondria were highly significant in MRCs. Mitochondrial vacuolization and despoiled mitochondria were closely associated with autophagosomes in MRCs. The multivesicular bodies (MVBs) and the exosome secretion pathway were observed in MRCs. Immunohistochemical staining of ion transport proteins indicated positive immunoreactivity of Na+/K+_ATPase (NKA) and Na+/K+/2Cl− cotransporter (NKCC) at the basal region of the mucosal surface. Likewise, the immunofluorescence staining results showed a strong positive localization of NKA, NKCC, and carbonic anhydrase (CA) at the basal and apical region of the mucosal surface of small intestine. Our findings suggest that MRCs provide support and regulate cellular ions for intestinal homeostasis and provide energy for cellular quality control in intestine.

scholarly journals In Vivo Autophagy Up-Regulation of Small Intestine Enterocytes in Chinese Soft-Shelled Turtles during Hibernation

Biomolecules ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 682 ◽  
Author(s):  
Waseem Ali Vistro ◽  
Yue Zhang ◽  
Xuebing Bai ◽  
Ping Yang ◽  
Yufei Huang ◽  
...  
Keyword(s):  
Small Intestine ◽  
Adenosine Monophosphate ◽  
Mucosal Surface ◽  
Multivesicular Bodies ◽  
Sequestosome 1 ◽  
Main Challenge ◽  
Transmission Electron ◽  
Late Endosomes ◽  
Positive Immunoreactivity

Many studies have focused on how autophagy plays an important role in intestinal homeostasis under pathological conditions. However, its role in the intestine during hibernation remains unclear. In the current study, we characterized in vivo up-regulation of autophagy in enterocytes of the small intestine of Chinese soft-shelled turtles during hibernation. Autophagy-specific markers were used to confirm the existence of autophagy in enterocytes through immunohistochemistry (IHC), immunofluorescence (IF), and immunoblotting. IHC staining indicated strong, positive immunoreactivity of the autophagy-related gene (ATG7), microtubule-associated protein light chain (LC3), and lysosomal-associated membrane protein 1 (LAMP1) within the mucosal surface during hibernation and poor expression during nonhibernation. IF staining results showed the opposite tendency for ATG7, LC3, and sequestosome 1 (p62). During hibernation ATG7 and LC3 showed strong, positive immunosignaling within the mucosal surface, while p62 showed strong, positive immunosignaling during nonhibernation. Similar findings were confirmed by immunoblotting. Moreover, the ultrastructural components of autophagy in enterocytes were revealed by transmission electron microscopy (TEM). During hibernation, the cumulative formation of phagophores and autophagosomes were closely associated with well-developed rough endoplasmic reticulum in enterocytes. These autophagosomes overlapped with lysosomes, multivesicular bodies, and degraded mitochondria to facilitate the formation of autophagolysosome, amphisomes, and mitophagy in enterocytes. Immunoblotting showed the expression level of PTEN-induced kinase 1 (PINK1), and adenosine monophosphate-activated protein kinase (AMPK) was enhanced during hibernation. Furthermore, the exosome secretion pathway of early–late endosomes and multivesicular bodies were closely linked with autophagosomes in enterocytes during hibernation. These findings suggest that the entrance into hibernation is a main challenge for reptiles to maintain homeostasis and cellular quality control in the intestine.

scholarly journals Persistent directional growth capability in Arabidopsis thaliana pollen tubes after nuclear elimination from the apex

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Kazuki Motomura ◽  
Hidenori Takeuchi ◽  
Michitaka Notaguchi ◽  
Haruna Tsuchi ◽  
Atsushi Takeda ◽  
...  
Keyword(s):  
Arabidopsis Thaliana ◽  
Pollen Tube ◽  
Sperm Cell ◽  
Pollen Tubes ◽  
Vegetative Nucleus ◽  
Sperm Cells ◽  
Apical Region ◽  
Basal Region ◽  
Specific Expression ◽  
Directional Growth

AbstractDuring the double fertilization process, pollen tubes deliver two sperm cells to an ovule containing the female gametes. In the pollen tube, the vegetative nucleus and sperm cells move together to the apical region where the vegetative nucleus is thought to play a crucial role in controlling the direction and growth of the pollen tube. Here, we report the generation of pollen tubes in Arabidopsis thaliana whose vegetative nucleus and sperm cells are isolated and sealed by callose plugs in the basal region due to apical transport defects induced by mutations in the WPP domain-interacting tail-anchored proteins (WITs) and sperm cell-specific expression of a dominant mutant of the CALLOSE SYNTHASE 3 protein. Through pollen-tube guidance assays, we show that the physiologically anuclear mutant pollen tubes maintain the ability to grow and enter ovules. Our findings provide insight into the sperm cell delivery mechanism and illustrate the independence of the tip-localized vegetative nucleus from directional growth control of the pollen tube.

Elementary auxin response chains at the plasma membrane involve external abp1 and multiple electrogenic ion transport proteins

1996 ◽  
Vol 18 (1-2) ◽  
pp. 23-28 ◽  
Author(s):  
H�l�ne Barbier-Brygoo ◽  
Sabine Zimmermann ◽  
S�bastien Thomine ◽  
Ian R. White ◽  
Paul Millner ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Ion Transport ◽  
Transport Proteins ◽  
Auxin Response ◽  
Electrogenic Ion Transport ◽  
Response Chains

Scanning Electron Microscopy and Resin Histology of Large Bowel Biopsies

1981 ◽  
Vol 26 (2) ◽  
pp. 103-114 ◽  
Author(s):  
Katherine E. Carr ◽  
A. L. Wong ◽  
D. G. Young ◽  
P. G. Toner ◽  
Chistine Watt
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Large Bowel ◽  
Human Colon ◽  
Mucosal Surface ◽  
Transmission Electron ◽  
Adults And Children ◽  
Scanning Electron

The mucosal surface of human colon in 18 adults and children was examined by S.E.M. with subsequent resin histology and transmission electron microscopy of the same specimen. Results showed that this technique contributed useful information on the mucosa in health and in disease.

scholarly journals Mites fluctuation population on peach tree (Prunus persica (L.) Batsch) and in associated plants

2011 ◽  
Vol 33 (3) ◽  
pp. 765-773 ◽  
Author(s):  
Carla Rosana Eichelberger ◽  
Liana Johann ◽  
Fernanda Majolo ◽  
Noeli Juarez Ferla
Keyword(s):  
Prunus Persica ◽  
Rio Grande ◽  
Population Diversity ◽  
Panonychus Ulmi ◽  
Apical Region ◽  
Basal Region ◽  
Rio Grande Do Sul ◽  
Phytophagous Mites ◽  
Phytoseiulus Macropilis ◽  
Tetranychus Ludeni

Despite the importance of peach (Prunus persica (L.) Batsch) in Rio Grande do Sul, little is known about mites fluctuation population considered important to this crop. The objective of this study was to know the population diversity and fluctuation of mite species associated with Premier and Eldorado varieties in Roca Sales and Venâncio Aires counties, Rio Grande do Sul. The study was conducted from July 2008 to June 2009 when 15 plants were randomly chosen in each area. The plants were divided in quadrants and from each one a branch was chosen from which three leaves were removed: one collected in the apical region, another in the medium and the other in the basal region, totalizing 180 leaves/area. Five of the most abundant associated plants were collected monthly in enough amounts for the screening under the stereoscopic microscope during an hour. A total of 1,124 mites were found belonging to 14 families and 28 species. Tetranychus ludeni Zacher, 1913, Panonychus ulmi (Koch, 1836) and Mononychellus planki (McGregor, 1950) were the most abundant phytophagous mites, whereas Typhlodromalus aripo Deleon, 1967 and Phytoseiulus macropilis (Banks, 1904) the most common predatory mites. The period of one hour under stereoscopic microscope was enough to get a representative sample. In both places evaluated the ecologic indices were low, but little higherin Premier (H' 0.56; EqJ: 0.43) when compared to Eldorado (H' 0.53; EqJ 0.40). In Premier constant species were not observed and accessory only Brevipalpus phoenicis (Geijskes, 1939), T. ludeni and T. aripo. Higher abundance was observed in December and January and bigger amount in April. Already in Eldorado, T. ludeni and P. ulmi were constants. Greater abundance was observed in November and December, whereas grater richness in December and January. In both orchards were not found mites in buds. Tetranychus ludeni is the most abundant phytophagous mites with outbreak population in November, December and January and high predator diversity was observed on associated plants and on peach plants, indicating the existence of species mobility in peach orchard.

scholarly journals Fine structure of the retinal pigment epithelium and cones of Antarctic fish Notohenia coriiceps Richardson in light and dark-conditions

2007 ◽  
Vol 24 (1) ◽  
pp. 33-40 ◽  
Author(s):  
Lucélia Donatti ◽  
Edith Fanta
Keyword(s):  
Epithelial Cells ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Antarctic Fish ◽  
Basal Region ◽  
Dense Cytoplasm ◽  
Transmission Electron ◽  
Notothenia Coriiceps ◽  
The Antarctic ◽  
Pigment Epithelial Cells

The Antarctic fish Notothenia coriiceps Richardson, 1844 lives in an environment of daily and annual photic variation and retina cells have to adjust morphologically to environmental luminosity. After seven day dark or seven day light acclimation of two groups of fish, retinas were extracted and processed for light and transmission electron microscopy. In seven day dark adapted, retina pigment epithelium melanin granules were aggregated at the basal region of cells, and macrophages were seen adjacent to the apical microvilli, between the photoreceptors. In seven day light adapted epithelium, melanin granules were inside the apical microvilli of epithelial cells and macrophages were absent. The supranuclear region of cones adapted to seven day light had less electron dense cytoplasm, and an endoplasmic reticulum with broad tubules. The mitochondria in the internal segment of cones adapted to seven day light were larger, and less electron dense. The differences in the morphology of cones and pigment epithelial cells indicate that N. coriiceps has retinal structural adjustments presumably optimizing vision in different light conditions.

scholarly journals Microscopical characterization of the salivary glands of the carnivorous cephalaspidean Philinopsis depicta (Mollusca, Opisthobranchia)

2009 ◽  
Vol 15 (S3) ◽  
pp. 39-40
Author(s):  
A. Lobo-da-Cunha ◽  
I. Ferreira ◽  
G. Calado
Keyword(s):  
Salivary Glands ◽  
Secretory Cells ◽  
Apical Region ◽  
Ciliated Cells ◽  
Transmission Electron ◽  
Herbivorous Species ◽  
Small Clusters ◽  
The Relationship ◽  
Apical Vacuole

AbstractCephalaspideans are a group of opisthobranch gastropods comprising carnivorous and herbivorous species, allowing an investigation of the relationship between these diets and the morphofunctional features of the salivary glands.In this study, the salivary glands of the carnivorous cephalaspidean Philinopsis depicta were observed by light microscopy using semithin sections and by transmission electron microscopy. A central duct runs along the length of these thin ribbon-shaped glands dividing them in two halves, each formed by a single row of tubules perpendicularly attached to the central duct. The simple epithelium of the central duct and lateral tubes contains ciliated cells and two types of secretory cells, named granular cells and cells with apical vacuole (Fig. 1). A very thin outer layer of connective tissue covers the epithelium (Fig. 1). The ciliated cells are numerous but very thin, forming small clusters between secretory cells. The nucleus, several mitochondria and a few lysosomes are located in the apical region were the cells are wider. A very thin cytoplasmic stalk reaches the base of the epithelium and contains bundles of filaments in addition to some mitochondria.

scholarly journals Localized Ca2+ uncaging reveals polarized distribution of Ca2+-sensitive Ca2+ release sites

2002 ◽  
Vol 158 (2) ◽  
pp. 283-292 ◽  
Author(s):  
Michael C. Ashby ◽  
Madeleine Craske ◽  
Myoung Kyu Park ◽  
Oleg V. Gerasimenko ◽  
Robert D. Burgoyne ◽  
...  
Keyword(s):  
Ryanodine Receptors ◽  
Acinar Cells ◽  
Cell Types ◽  
Pancreatic Acinar Cells ◽  
Apical Region ◽  
Basal Region ◽  
Activation Pattern ◽  
Inositol Trisphosphate Receptors ◽  
Agonist Stimulation ◽  
Major Process

Ca2+-induced Ca2+ release (CICR) plays an important role in the generation of cytosolic Ca2+ signals in many cell types. However, it is inherently difficult to distinguish experimentally between the contributions of messenger-induced Ca2+ release and CICR. We have directly tested the CICR sensitivity of different regions of intact pancreatic acinar cells using local uncaging of caged Ca2+. In the apical region, local uncaging of Ca2+ was able to trigger a CICR wave, which propagated toward the base. CICR could not be triggered in the basal region, despite the known presence of ryanodine receptors. The triggering of CICR from the apical region was inhibited by a pharmacological block of ryanodine or inositol trisphosphate receptors, indicating that global signals require coordinated Ca2+ release. Subthreshold agonist stimulation increased the probability of triggering CICR by apical uncaging, and uncaging-induced CICR could activate long-lasting Ca2+ oscillations. However, with subthreshold stimulation, CICR could still not be initiated in the basal region. CICR is the major process responsible for global Ca2+ transients, and intracellular variations in sensitivity to CICR predetermine the activation pattern of Ca2+ waves.

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