The epithelial luminescent system of Chaetopterus variopedatus

1979 ◽  
Vol 57 (6) ◽  
pp. 1290-1310 ◽  
Author(s):  
Michel Anctil
Keyword(s):  
Light Emission ◽  
Cell Types ◽  
Control Mechanisms ◽  
Mucous Cells ◽  
Apical Pore ◽  
Fluorescence And Electron Microscopy ◽  
Chaetopterus Variopedatus ◽  
Secretory Products ◽  
Light Fluorescence ◽  
Supportive Cells

The epithelial luminescent gland of the aliform notopods of Chaetopterus variopedatus was investigated by light, fluorescence, and electron microscopy. Among the cell types present, the orthochromatic cells are closely associated with the luminescent zones and, based on fluorescence microscopy, are probably the photoprotein-containing photocytes. The orthochromatic as well as the few mucous cells of the luminescent epithelia are exocrine goblet cells that synthesize, pack and release large amounts of secretory products through an apical pore. Biconcave cells containing peroxisome-like granules and contributing the brush border microvilli of the epithelium are suspected to participate in the light emission process. Supportive cells packed with microfilaments are closely associated with the orthochromatic and mucous cells and probably mediate the extrusion of secretory materials and the ensuing luminescence after stimulation. A few multiciliated cells are also present.A subepidermal plexus underlies the luminescent epithelium and includes a large number of peripheral nerves and neurites ensheathed by large gliointerstitial cells and processes. Direct neuroeffector cell contacts are absent except for a few close appositions between neurites and supportive cells. The structural organization of the epithelium and of the nerve plexus is discussed in relation to possible neural and cellular control mechanisms in bioluminescence.

scholarly journals Electron Microscopic Immunogold Localization of Salivary Mucins MG1 and MG2 in Human Submandibular and Sublingual Glands

2003 ◽  
Vol 51 (1) ◽  
pp. 69-79 ◽  
Author(s):  
Marco Piludu ◽  
Sean A. Rayment ◽  
Bing Liu ◽  
Gwynneth D. Offner ◽  
Frank G. Oppenheim ◽  
...  
Keyword(s):  
Salivary Glands ◽  
Expression Patterns ◽  
Cell Types ◽  
Mucous Cells ◽  
Electron Microscopic ◽  
Thin Sections ◽  
Dense Cores ◽  
Duct Cells ◽  
Rabbit Igg ◽  
Lowicryl K4m

The human salivary mucins MG1 and MG2 are well characterized biochemically and functionally. However, there is disagreement regarding their cellular and glandular sources. The aim of this study was to define the localization and distribution of these two mucins in human salivary glands using a postembedding immunogold labeling method. Normal salivary glands obtained at surgery were fixed in 3% paraformaldehyde-0.1% glutaraldehyde and embedded in Lowicryl K4M or LR Gold resin. Thin sections were labeled with rabbit antibodies to MG1 or to an N-terminal synthetic peptide of MG2, followed by gold-labeled goat anti-rabbit IgG. The granules of all mucous cells of the submandibular and sublingual glands were intensely reactive with anti-MG1. No reaction was detected in serous cells. With anti-MG2, the granules of both mucous and serous cells showed reactivity. The labeling was variable in both cell types, with mucous cells exhibiting a stronger reaction in some glands and serous cells in others. In serous granules, the electron-lucent regions were more reactive than the dense cores. Intercalated duct cells near the acini displayed both MG1 and MG2 reactivity in their apical granules. In addition, the basal and lateral membranes of intercalated duct cells were labeled with anti-MG2. These results confirm those of earlier studies on MG1 localization in mucous cells and suggest that MG2 is produced by both mucous and serous cells. They also indicate differences in protein expression patterns among salivary serous cells.

scholarly journals Automated analysis of filopodial length and spatially resolved protein concentration via adaptive shape tracking

2016 ◽  
Vol 27 (22) ◽  
pp. 3616-3626 ◽  
Author(s):  
Tanumoy Saha ◽  
Isabel Rathmann ◽  
Abhiyan Viplav ◽  
Sadhana Panzade ◽  
Isabell Begemann ◽  
...  
Keyword(s):  
Protein Concentration ◽  
Growth Dynamics ◽  
Automated Analysis ◽  
Cell Types ◽  
Control Mechanisms ◽  
Spatially Resolved ◽  
Novel Approach ◽  
Associated Proteins

Filopodia are dynamic, actin-rich structures that transiently form on a variety of cell types. To understand the underlying control mechanisms requires precise monitoring of localization and concentration of individual regulatory and structural proteins as filopodia elongate and subsequently retract. Although several methods exist that analyze changes in filopodial shape, a software solution to reliably correlate growth dynamics with spatially resolved protein concentration along the filopodium independent of bending, lateral shift, or tilting is missing. Here we introduce a novel approach based on the convex-hull algorithm for parallel analysis of growth dynamics and relative spatiotemporal protein concentration along flexible filopodial protrusions. Detailed in silico tests using various geometries confirm that our technique accurately tracks growth dynamics and relative protein concentration along the filopodial length for a broad range of signal distributions. To validate our technique in living cells, we measure filopodial dynamics and quantify spatiotemporal localization of filopodia-associated proteins during the filopodial extension–retraction cycle in a variety of cell types in vitro and in vivo. Together these results show that the technique is suitable for simultaneous analysis of growth dynamics and spatiotemporal protein enrichment along filopodia. To allow readily application by other laboratories, we share source code and instructions for software handling.

Artificial metaplasia of pigmented epithelium into retina in tadpoles and adult frogs

Development ◽  
1972 ◽  
Vol 28 (3) ◽  
pp. 521-546
Author(s):  
G. V. Lopashov ◽  
Alla A. Sologub
Keyword(s):  
Rana Temporaria ◽  
Cell Types ◽  
Control Mechanisms ◽  
General Control ◽  
Pigmented Epithelium ◽  
The Stability

The present work was aimed at investigating the possibility and conditions necessary for the artificial transformation of one tissue into another. Experiments were carried out with the pigmented epithelium of the eye in tadpoles and adult frogs of Rana temporaria. Following the removal of the mesenchyme envelopes (or their exfoliation during the experiment), pigmented epithelium transformed into retina under the influence of retina from tadpoles of the same species. This phenomenon was observed both under the cultivation of a piece of retina in a sandwich of pigmented epithelium and the transplantation of pigmented epithelium layers into the eye cavity of tadpoles. Such transformation did not occur in the absence of retinal influence. Metaplasia requires the removal of the mesenchyme envelopes, the action of the retinal agent, as well as preservation of the integrity of the pigmented epithelium layer and subsequent proliferation of its cells. The character of general control mechanisms both maintaining the stability of cell types and leading to their transformation into other cell types is discussed.

Growth and differentiation of Tubularia cells in a chemically defined physiological medium

Development ◽  
1968 ◽  
Vol 20 (1) ◽  
pp. 73-80
Author(s):  
Allison L. Burnett ◽  
Faith E. Ruffing ◽  
June Zongker ◽  
Anna Necco
Keyword(s):  
Defined Medium ◽  
Control Mechanisms ◽  
Mucous Cells ◽  
Chemically Defined Medium ◽  
Experimental Animals ◽  
Molecular Weights ◽  
Large Numbers ◽  
High Degree ◽  
I Cells

Although hydroids have proven valuable experimental animals for studies involving polarity and regeneration, they have not been extensively used by chemical embryologists studying control mechanisms in differentiation. Ideally, hydroids should be valuable tools for such a study. Their morpohology is relatively simple since they are diploblastic; their cells achieve a high degree of specialization (cnidoblasts, nerve cells, gland and mucous cells); cell differentiation (and morphogenesis) from a reserve stock of interstitial or i-cells is rapid; and many species can be cultured in large numbers under controlled environmental conditions. Probably one of the reasons for this lack of attention is that no one has succeeded in cloning cells of a particular type in a chemically defined medium. In vivo systems, mainly because of their impermeability to most exogenous materials with molecular weights over 200, have not proven to be especially reliable.

scholarly journals Alternative Pathways of Cancer Cell Death by Rottlerin: Apoptosis versus Autophagy

2012 ◽  
Vol 2012 ◽  
pp. 1-11 ◽  
Author(s):  
Claudia Torricelli ◽  
Sara Salvadori ◽  
Giuseppe Valacchi ◽  
Karel Souček ◽  
Eva Slabáková ◽  
...  
Keyword(s):  
Cell Death ◽  
Cancer Cells ◽  
Cancer Cell ◽  
Electron Microscopic Examination ◽  
Cell Types ◽  
Beclin 1 ◽  
Electron Microscopic ◽  
Alternative Pathways ◽  
Light Fluorescence ◽  
Mcf 7

Since the ability of cancer cells to evade apoptosis often limits the efficacy of radiotherapy and chemotherapy, autophagy is emerging as an alternative target to promote cell death. Therefore, we wondered whether Rottlerin, a natural polyphenolic compound with antiproliferative effects in several cell types, can induce cell death in MCF-7 breast cancer cells. The MCF-7 cell line is a good model of chemo/radio resistance, being both apoptosis and autophagy resistant, due to deletion of caspase 3 gene, high expression of the antiapoptotic protein Bcl-2, and low expression of the autophagic Beclin-1 protein. The contribution of autophagy and apoptosis to the cytotoxic effects of Rottlerin was examined by light, fluorescence, and electron microscopic examination and by western blotting analysis of apoptotic and autophagic markers. By comparing caspases-3-deficient (MCF-73def) and caspases-3-transfected MCF-7 cells (MCF-73trans), we found that Rottlerin induced a noncanonical, Bcl-2-, Beclin 1-, Akt-, and ERK-independent autophagic death in the former- and the caspases-mediated apoptosis in the latter, in not starved conditions and in the absence of any other treatment. These findings suggest that Rottlerin could be cytotoxic for different cancer cell types, both apoptosis competent and apoptosis resistant.

scholarly journals Chaetopterus variopedatus Bioluminescence: A Review of Light Emission within a Species Complex

2020 ◽  
Vol 96 (4) ◽  
pp. 768-778
Author(s):  
Jeremy D. Mirza ◽  
Álvaro E. Migotto ◽  
Ilia V. Yampolsky ◽  
Gabriela V. de Moraes ◽  
Aleksandra S. Tsarkova ◽  
...  
Keyword(s):  
Species Complex ◽  
Light Emission ◽  
Chaetopterus Variopedatus

scholarly journals Differential regulation of spleen cell-mediated eosinophil and neutrophil-macrophage production

Blood ◽  
1980 ◽  
Vol 55 (3) ◽  
pp. 489-493 ◽  
Author(s):  
SH Bartelmez ◽  
WH Dodge ◽  
DA Bass
Keyword(s):  
Growth Factor ◽  
Contrast Media ◽  
Spleen Cell ◽  
Trichinella Spiralis ◽  
Cell Types ◽  
Differential Regulation ◽  
Spleen Cells ◽  
Secretory Products ◽  
Kinetics Of

Abstract Nonadherent spleen cells of mice infected with Trichinella spiralis released growth stimulatory factors (GSFs) in vitro when challenged with excretory/secretory products of muscle stage larvae. The assay of GSF was based on proliferation of normal, nonadherent syngeneic marrow cells in liquid tube cultures. Media conditioned for 1 day by challenged spleen cells stimulated eosinophil production but failed to stimulate production of other cell types. In contrast, media conditioned for 5 days supported eosinophil, neutrophil, and macrophage production. The kinetics of cell production were also different. Eosinophil production started within 1 day, reached a peak at day 2, and was down to control levels by day 4. In contrast, neutrophil/macrophage production began between 2 and 4 days and reached a peak at 6--8 days. The short duration of eosinophil production was evidently due to depletion of growth-factor-responsive cells.

scholarly journals A novel method to enhance the sensitivity of marker detection using a refined hierarchical prior of tissue similarities

2015 ◽  
Author(s):  
Shahin Mohammadi ◽  
Ananth Grama
Keyword(s):  
Immune Cells ◽  
Statistical Approach ◽  
Signal To Noise Ratio ◽  
Cell Types ◽  
Detection Methods ◽  
Control Mechanisms ◽  
Tissue Specific ◽  
Cellular Machinery ◽  
Marker Detection ◽  
Brain Tissues

Identification of biochemical processes that drive the transformation of a totipotent cell into various cell types is essential to our understanding of living systems. This complex machinery determines how tissues differ in terms of their anatomy, physiology, morphology, and, more importantly, how various cellular control mechanisms contribute to the observed similarities/ differences. Tissue-selective genes orchestrate various aspects of cellular machinery in different tissues, and are known to be implicated in a number of tissue-specific pathologies. We propose a novel statistical approach that identifies and removes the effect of universally expressed genes in groups of tissues. This allows us to better characterize tissue similarities, as well as to identify tissue-selective genes. We use our method to construct a reliable hierarchy of tissue similarities. The groupings of tissues in this hierarchy are used to specify successively refined priors for identifying tissue-selective functions and their corresponding genes in the reduced subspace. We show that our refinement process enhances the signal-to-noise ratio in the identification of markers. Using case studies of immune cells and brain tissues, we show that our approach significantly outperforms the state-of-the-art methods, both in terms of coverage and reliability of the predicted tissue-selective genes. Our statistical approach provides a general framework for enhancing the sensitivity of marker detection methods, which can be used in conjunction with other techniques. Even in cases where the number of available expression datasets is limited, we show that our marker detection method outperforms existing techniques. We present detailed validation on immune cells and brain tissues in this paper. Our approach can be applied to construct similar datasets of other human tissues as well, for identifying tissue-specific genes. We demonstrate how these tissue-selective genes enhance our understanding of differentiating biochemical features of brain tissues, shed light on how tissue-selective pathologies progress, and help us identify specific biomarkers and targets for future interventions.

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