scholarly journals SPECULATIONS BASED ON THE MORPHOLOGY OF THE GOLGI SYSTEMS IN SEVERAL TYPES OF PROTEIN-SECRETING CELLS

1962 ◽  
Vol 15 (1) ◽  
pp. 45-54 ◽  
Author(s):  
R. F. Zeigel ◽  
A. J. Dalton
Keyword(s):  
Cell Types ◽  
Secretory Product ◽  
Transition Elements ◽  
Golgi Region ◽  
Small Variety ◽  
Intracellular Organelles ◽  
Electron Microscopical ◽  
Relationship Of ◽  
The Relationship ◽  
Protein Secreting

Electron microscopical observations on the relationship of the Golgi region to other intracellular organelles in certain protein-secreting cells have substantiated and extended existing hypotheses. In micrographs of several cell types, the juxtanuclear Golgi regions were observed to be closely associated with nuclear "pores." The "transition elements" of the ergastoplasmic membranes possess "blebs" which may represent a transport process facilitating the movement of intracisternal contents into the Golgi zone. A "blebbing" process of this nature may be one source of the small variety of Golgi vesicles. Zymogen granules of different densities were observed and their significance was postulated. Light Golgi vacuoles were observed. It is suggested that these vacuoles represent accumulations of relatively fluid material segregated from the secretory product in these cell types. These hypotheses from inferential evidence are discussed and extended.

The caveolar-mitochondrial interface: regulation of cellular metabolism in physiology and pathophysiology

2020 ◽  
Vol 48 (1) ◽  
pp. 165-177 ◽  
Author(s):  
Cerrone R. Foster ◽  
Shiho Satomi ◽  
Yuko Kato ◽  
Hemal H. Patel
Keyword(s):  
Plasma Membrane ◽  
Cellular Metabolism ◽  
Primary Factor ◽  
Cellular Organelle ◽  
Membrane Microdomain ◽  
Intracellular Communication ◽  
Intracellular Organelles ◽  
Relationship Of ◽  
The Relationship

The plasma membrane is an important cellular organelle that is often overlooked in terms of a primary factor in regulating physiology and pathophysiology. There is emerging evidence to suggest that the plasma membrane serves a greater purpose than a simple barrier or transporter of ions. New paradigms suggest that the membrane serves as a critical bridge to connect extracellular to intracellular communication particularly to regulate energy and metabolism by forming physical and biochemical associations with intracellular organelles. This review will focus on the relationship of a particular membrane microdomain — caveolae — with mitochondria and the particular implication of this to physiology and pathophysiology.

Characterization of a novel nuclear envelope protein restricted to certain cell types

1988 ◽  
Vol 90 (2) ◽  
pp. 237-245
Author(s):  
J.M. Lord ◽  
J.A. Thick ◽  
C.M. Bunce ◽  
A.M. Taylor ◽  
P.H. Gallimore ◽  
...  
Keyword(s):  
Nuclear Envelope ◽  
Envelope Protein ◽  
Cell Types ◽  
Integral Membrane Protein ◽  
Nuclear Pores ◽  
Cellular Processes ◽  
Relationship Of ◽  
The Relationship ◽  
Insight Into

The monoclonal antibody AGF2.3 identifies a nuclear envelope protein that is restricted to certain cell types. In particular, this antigen shows a reduced level of expression during haemopoietic cell maturation. In this study, we have examined the relationship of this protein to known nuclear envelope proteins that have a similar molecular mass. Antigen extraction and immunoelectron microscope studies revealed that the AGF2.3 protein is an integral membrane protein present at both the inner and outer aspects of the nuclear envelope. The protein is not associated with nuclear pores and therefore is distinct from pore complex proteins. The AGF2.3 protein does not have ATPase activity. Therefore, this protein is also distinct from a myosin heavy chain-like ATPase that is associated with the nuclear envelope. The AGF2.3 antibody identifies a novel nuclear envelope protein. Further studies of the biochemical nature of the AGF2.3 protein should provide insight into novel cellular processes at the nuclear envelope relating to the lineage or maturation status of cells.

scholarly journals Properties of Ventral Cerebral Neurones Involved in the Feeding System of the Snail, Lymnaea Stagnalis

1984 ◽  
Vol 108 (1) ◽  
pp. 257-272
Author(s):  
C. R. MCCROHAN
Keyword(s):  
Lymnaea Stagnalis ◽  
Rhythmic Activity ◽  
Cell Types ◽  
Feeding System ◽  
Oral Aperture ◽  
Axonal Projections ◽  
Cerebral Ganglia ◽  
Buccal Ganglia ◽  
Relationship Of ◽  
The Relationship

Four identified neurone types (CV3, 7, 5 and 6), located in the ventral cerebral ganglia of Lymnaea stagnalis, are described. These cells have axonal projections in one or more of the nerves innervating the lips. In addition, they show rhythmic synaptic inputs leading to strong burst activity in phase with cyclic output from the buccal ganglia, suggesting a role in the control of the oral aperture during feeding. The innervation of lip muscle by one of the cell types (CV7) is confirmed electrophysiologically. The relationship of rhythmic activity in CV cells with that in the buccal feeding system is discussed.

scholarly journals Imaging and Manipulating Pituitary Function in the Awake Mouse

Endocrinology ◽  
2019 ◽  
Vol 160 (10) ◽  
pp. 2271-2281 ◽  
Author(s):  
Ombeline Hoa ◽  
Chrystel Lafont ◽  
Pierre Fontanaud ◽  
Anne Guillou ◽  
Yasmine Kemkem ◽  
...  
Keyword(s):  
Pituitary Gland ◽  
Cell Types ◽  
Temporal Regulation ◽  
Hypothalamic Regulation ◽  
Health And Disease ◽  
Multiple Cell ◽  
Relationship Of ◽  
The Relationship ◽  
The Brain

Abstract Extensive efforts have been made to explore how the activities of multiple brain cells combine to alter physiology through imaging and cell-specific manipulation in different animal models. However, the temporal regulation of peripheral organs by the neuroendocrine factors released by the brain is poorly understood. We have established a suite of adaptable methodologies to interrogate in vivo the relationship of hypothalamic regulation with the secretory output of the pituitary gland, which has complex functional networks of multiple cell types intermingled with the vasculature. These allow imaging and optogenetic manipulation of cell activities in the pituitary gland in awake mouse models, in which both neuronal regulatory activity and hormonal output are preserved. These methodologies are now readily applicable for longitudinal studies of short-lived events (e.g., calcium signals controlling hormone exocytosis) and slowly evolving processes such as tissue remodeling in health and disease over a period of days to weeks.

scholarly journals Myelin Repair: From Animal Models to Humans

2021 ◽  
Vol 15 ◽  
Author(s):  
Myriam Cayre ◽  
Marie Falque ◽  
Océane Mercier ◽  
Karine Magalon ◽  
Pascale Durbec
Keyword(s):  
Animal Models ◽  
Cell Types ◽  
Experimental Models ◽  
Matrix Proteins ◽  
Oligodendrocyte Progenitor Cells ◽  
Myelin Repair ◽  
The Central Nervous System ◽  
Relationship Of ◽  
The Relationship

It is widely thought that brain repair does not occur, but myelin regeneration provides clear evidence to the contrary. Spontaneous remyelination may occur after injury or in multiple sclerosis (MS). However, the efficiency of remyelination varies considerably between MS patients and between the lesions of each patient. Myelin repair is essential for optimal functional recovery, so a profound understanding of the cells and mechanisms involved in this process is required for the development of new therapeutic strategies. In this review, we describe how animal models and modern cell tracing and imaging methods have helped to identify the cell types involved in myelin regeneration. In addition to the oligodendrocyte progenitor cells identified in the 1990s as the principal source of remyelinating cells in the central nervous system (CNS), other cell populations, including subventricular zone-derived neural progenitors, Schwann cells, and even spared mature oligodendrocytes, have more recently emerged as potential contributors to CNS remyelination. We will also highlight the conditions known to limit endogenous repair, such as aging, chronic inflammation, and the production of extracellular matrix proteins, and the role of astrocytes and microglia in these processes. Finally, we will present the discrepancies between observations in humans and in rodents, discussing the relationship of findings in experimental models to myelin repair in humans. These considerations are particularly important from a therapeutic standpoint.

Receptive fields and functional architecture of macaque V2

1994 ◽  
Vol 71 (6) ◽  
pp. 2517-2542 ◽  
Author(s):  
J. B. Levitt ◽  
D. C. Kiper ◽  
J. A. Movshon
Keyword(s):  
Receptive Fields ◽  
Cell Types ◽  
Macaque Monkey ◽  
Area V2 ◽  
Distinct Cell ◽  
Visual Areas ◽  
Layer 4 ◽  
Different Response ◽  
Relationship Of ◽  
The Relationship

1. Visual area V2 of macaque monkey cerebral cortex is the largest of the extrastriate visual areas, yet surprisingly little is known of its neuronal properties. We have made a quantitative analysis of V2 receptive field properties. Our set of measurements was chosen to distinguish neuronal responses reflecting parvocellular (P) or magnocellular (M) inputs and to permit comparison with similar measurements made in other visual areas; we further describe the relationship of those properties to the laminar and cytochrome oxidase (CO) architecture of V2. 2. We recorded the activity of single units representing the central 5 degrees in all laminae and CO divisions of V2 in anesthetized, paralyzed macaque monkeys. We studied responses to geometric targets and to drifting sinusoidal gratings that varied in orientation, spatial frequency, drift rate, contrast, and color. 3. The orientation selectivity and spatial and temporal tuning of V2 neurons differed little from those in V1. As in V1, spatial and temporal tuning in V2 appeared separable, and we identified a population of simple cells (more common within the central 3 degrees) similar to those found in V1. Contrast sensitivity of V2 neurons was greater on average than in V1, perhaps reflecting the summation of inputs in V2's larger receptive fields. Many V2 neurons exhibited some degree of chromatic opponency, responding to isoluminant color variations, but these neurons differed from V1 in the linearity with which they summate cone signals. 4. In agreement with others, we found that neurons with selective responses to color, size, and motion did seem to cluster in different CO compartments. However, this segregation of qualitatively different response selectivities was not absolute, and response properties also seemed to depend on laminar position within each compartment. As others also have noted, we found that CO stripe widths in the macaque (unlike in the squirrel monkey) did not consistently appear different. We relied on the segregation of qualitatively distinct cell types, and in some cases the pattern of Cat-301 staining as well, to distinguish CO stripes when the staining pattern of CO alone was ambiguous. Although all cell types were found in all CO compartments and laminae, unoriented cells were more prominent in layers 2–4 of “thin” stripes, direction-selective cells in layers 3B/4 of “thick” stripes, color-selective cells in the upper layers of thin and pale stripes, and end-stopped cells mainly outside of layer 4 in thin stripes.(ABSTRACT TRUNCATED AT 400 WORDS)

scholarly journals The Role of Heritable Tumors in Evolution of Development: a New Theory of Carcino-evo-devo

Acta Naturae ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 65-72
Author(s):  
A P Kozlov
Keyword(s):  
Normal Development ◽  
Wide Spectrum ◽  
Cell Types ◽  
Evolution Of Development ◽  
Main Hypothesis ◽  
Hereditary Tumors ◽  
Evo Devo ◽  
Relationship Of ◽  
The Relationship

The hypothesis of evolution by tumor neofunctionalization (the main hypothesis) describes the possible role of hereditary tumors in evolution. The present article examines the relationship of the main hypothesis to other biological theories. As shown in this paper, the main hypothesis does not contradict to the existing biological theories, but fills the lacunas between them and explains some unexplained (or not completely understood) questions. Common features of embryonic development and tumorigenesis are described by several recognized theories. Similarities between normal development and tumorigenesis suggest that tumors could participate in the evolution of ontogenesis and in the origin of new cell types, tissues and organs. A wide spectrum of non-trivial explanations and non-trivial predictions in different fields of biology, suggested by the main hypothesis, is an indication of its fundamental nature and the potential to become a new biological theory, a theory of the role of tumors in evolution of development, or carcino-evo-devo.

scholarly journals Distinct ATOH1 and Neurog3 requirements define tuft cells as a new secretory cell type in the intestinal epithelium

2011 ◽  
Vol 192 (5) ◽  
pp. 767-780 ◽  
Author(s):  
François Gerbe ◽  
Johan H. van Es ◽  
Leila Makrini ◽  
Bénédicte Brulin ◽  
Georg Mellitzer ◽  
...  
Keyword(s):  
Stem Cells ◽  
Intestinal Epithelium ◽  
Secretory Cell ◽  
Cell Types ◽  
Epithelial Stem Cells ◽  
Tuft Cells ◽  
Quiescent Stem Cells ◽  
Putative Marker ◽  
Relationship Of ◽  
The Relationship

The unique morphology of tuft cells was first revealed by electron microscopy analyses in several endoderm-derived epithelia. Here, we explore the relationship of these cells with the other cell types of the intestinal epithelium and describe the first marker signature allowing their unambiguous identification. We demonstrate that although mature tuft cells express DCLK1, a putative marker of quiescent stem cells, they are post-mitotic, short lived, derive from Lgr5-expressing epithelial stem cells, and are found in mouse and human tumors. We show that whereas the ATOH1/MATH1 transcription factor is essential for their differentiation, Neurog3, SOX9, GFI1, and SPDEF are dispensable, which distinguishes these cells from enteroendocrine, Paneth, and goblet cells, and raises from three to four the number of secretory cell types in the intestinal epithelium. Moreover, we show that tuft cells are the main source of endogenous intestinal opioids and are the only epithelial cells that express cyclooxygenase enzymes, suggesting important roles for these cells in the intestinal epithelium physiopathology.

Nonsteroidal signals originating in the gonads

1992 ◽  
Vol 72 (3) ◽  
pp. 731-787 ◽  
Author(s):  
J. F. Ackland ◽  
N. B. Schwartz ◽  
K. E. Mayo ◽  
R. E. Dodson
Keyword(s):  
Growth Promotion ◽  
Cell Types ◽  
Molecular Probes ◽  
Number Of Factors ◽  
Peptide Signals ◽  
Relationship Of ◽  
The Relationship ◽  
Follicle Selection

The discovery of the various peptide factors in the gonads followed different paths. A number of factors were specifically searched for because of physiological experiments that predicted that an activity from the gonads was necessary to explain phenomena. Such was the case for gonadal steroids and for such peptide factors as inhibin, MIS, OMI, FRP, seminal plasma inhibin, relaxin, PA factor and other proteases, and ABP. In the process other factors such as activin and follistatin were serendipitously discovered. A second group of factors was discovered because in vitro experiments of various combinations of gonadal cell types failed to replicate in vivo findings, suggesting missing signals. Such substances are the panoply of growth factors aiding in differentiation and growth promotion and inhibition: LS and LI, P-Mod-S, clusterin, and various components of the ECM. Finally, and most recently, another set of peptides has been identified because immunological or molecular probes have been used to search gonadal tissue for factors originally discovered elsewhere; these include POMC, GnRH-like peptide, oxytocin, AVP, angiotensin, ANF, CRF, neural peptides, and c-mos. Our understanding of the relationship of most of these peptides to the local signals necessary for gonadal function is still very elementary. Clearly some like relaxin and inhibin function as important hormones, and ABP, for example, probably functions importantly in transporting testosterone down the tubule. Most local paracrine or autocrine peptide signals appear to act in relationship to gonadotropin levels probably in local differentiation in the process of gamete maturation, but this is only conjecture at this point. No experimental verification that any of these factors is involved in follicle selection for recruitment or for atresia is yet available. For many of the factors local receptors have not yet been identified. The richness of the variety of peptides in the gonads suggests that microanalysis of cell-cell signaling would be rewarding, but at the time of this writing such investigations are not yet possible.

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