Topography of Ca2+-sequestering endoplasmic reticulum in photoreceptors and pigmented glial cells in the compound eye of the honeybee drone

1989 ◽  
Vol 255 (3) ◽  
Author(s):  
O. Baumann ◽  
B. Walz
Keyword(s):  
Endoplasmic Reticulum ◽  
Glial Cells ◽  
Compound Eye ◽  
Honeybee Drone

Effect of pranoprofen on endoplasmic reticulum stress in the primary cultured glial cells

2009 ◽  
Vol 54 (1) ◽  
pp. 1-6 ◽  
Author(s):  
Toru Hosoi ◽  
Miyako Sasaki ◽  
Sachiko Baba ◽  
Koichiro Ozawa
Keyword(s):  
Endoplasmic Reticulum ◽  
Endoplasmic Reticulum Stress ◽  
Glial Cells

Origine et formation de différents types de vacuoles induites par la multiplication d'Alphavirus Sindbis dans divers systemes cellulaires

1979 ◽  
Vol 25 (12) ◽  
pp. 1452-1459 ◽  
Author(s):  
Yves Lombard ◽  
Philippe Poindron ◽  
Aimé Porte
Keyword(s):  
Endoplasmic Reticulum ◽  
Glial Cells ◽  
Chicken Embryo ◽  
Cytoplasmic Membrane ◽  
Dense Material ◽  
Newborn Mice ◽  
Electron Dense Material ◽  
Double Membrane ◽  
Single Membrane ◽  
Chicken Embryo Fibroblasts

Spherule-containing vacuoles and nucleocapsid-bearing vacuoles (cytopathic vacuoles types 1 and 2 respectively of Grimley et al. 1968) induced by Alphavirus Sindbis were studied in brains from newborn mice, chicken embryo fibroblasts, and two lines of tumoral glial cells from muridae. Endoplasmic reticulum (ER) elements and finely granular electron-dense material also seen in contact with nucleocapsids seemed to be involved in the formation of the classical single-membrane spherule-containing vacuoles. A second type of spherule-containing vacuoles were characterized by their double membrane and an amorphous electron-dense content and were probably derived from mitochondria. Nucleocapsid-bearing vacuoles were formed from modified ER elements and seemed to be linked to excessive synthesis of viral material. Such ER alterations were not observed in RG6 cells. In these cells, there were only spherule-containing vacuoles, while nucleocapsids were seen associated with the cytoplasmic membrane only.

scholarly journals Functional morphology of the divided compound eye of the honeybee drone (Apis mellifera)

1991 ◽  
Vol 23 (4) ◽  
pp. 525-535 ◽  
Author(s):  
J.G. Menzel ◽  
H. Wunderer ◽  
D.G. Stavenga
Keyword(s):  
Apis Mellifera ◽  
Functional Morphology ◽  
Compound Eye ◽  
Honeybee Drone

scholarly journals Expression of the Endoplasmic Reticulum Stress Marker GRP78 in the Normal Retina and Retinal Degeneration Induced by Blue LED Stimuli in Mice

Cells ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 995
Author(s):  
Yong Soo Park ◽  
Hong-Lim Kim ◽  
Seung Hee Lee ◽  
Yan Zhang ◽  
In-Beom Kim
Keyword(s):  
Endoplasmic Reticulum ◽  
Retinal Degeneration ◽  
Glial Cells ◽  
Cell Activation ◽  
Outer Nuclear Layer ◽  
Photoreceptor Cells ◽  
Dependent Manner ◽  
Normal Retina ◽  
Perinuclear Space ◽  
The Unfolded Protein Response

Retinal degeneration is a leading cause of blindness. The unfolded protein response (UPR) is an endoplasmic reticulum (ER) stress response that affects cell survival and death and GRP78 forms a representative protective response. We aimed to determine the exact localization of GRP78 in an animal model of light-induced retinal degeneration. Dark-adapted mice were exposed to blue light-emitting diodes and retinas were obtained at 24 h and 72 h after exposure. In the normal retina, we found that GRP78 was rarely detected in the photoreceptor cells while it was expressed in the perinuclear space of the cell bodies in the inner nuclear and ganglion cell layers. After injury, the expression of GRP78 in the outer nuclear and inner plexiform layers increased in a time-dependent manner. However, an increased GRP78 expression was not observed in damaged photoreceptor cells in the outer nuclear layer. GRP78 was located in the perinuclear space and ER lumen of glial cells and the ER developed in glial cells during retinal degeneration. These findings suggest that GRP78 and the ER response are important for glial cell activation in the retina during photoreceptor degeneration.

scholarly journals Amyloid Beta oligomers prevents Lysosomal targeting of miRNP to stop its recycling and target repression in glial cells

2021 ◽  
Author(s):  
Dipayan De ◽  
Suvendra N. Bhattacharyya
Keyword(s):  
Endoplasmic Reticulum ◽  
Glial Cells ◽  
Amyloid Beta ◽  
Rna Processing ◽  
Mrna Targets ◽  
Lysosomal Targeting ◽  
Body Components ◽  
Processing Body ◽  
Cytokine Mrnas ◽  
Lysosomal Protein

On exposure to Amyloid Beta Oligomers (Aβ1-42), glial cells start expressing proinflammatory cytokines although there has been increase in repressive miRNAs levels as well. Exploring the mechanism of this potential immunity of target cytokine mRNAs against repressive miRNAs in amyloid beta exposed glial cells, we have identified differential compartmentalization of repressive miRNAs in glial cells to explain this aberrant miRNA function. While the target mRNAs were found to be associated with polysomes attached to endoplasmic reticulum, the miRNPs found to be present predominantly with endosomes that failed to recycle to endoplasmic reticulum attached polysomes to repress mRNA targets in Aβ1-42 treated cells. Aβ1-42 oligomers, by masking the Rab7 proteins on endosomal surface, affects Rab7 interaction with Rab Interacting Lysosomal Protein (RILP) to restrict lysosomal targeting and recycling of miRNPs. RNA processing body or P-body localization of the miRNPs also get enhanced in amyloid beta treated cells as a consequence of enhanced endosomal retention of miRNPs. Interestingly, depletion of P-body components partly rescues the miRNA function in glial cells exposed to amyloid beta and restricts the excess cytokine expression there.

scholarly journals PGY Repeats and N-Glycans Govern the Trafficking of Paranodin and Its Selective Association with Contactin and Neurofascin-155

2007 ◽  
Vol 18 (1) ◽  
pp. 229-241 ◽  
Author(s):  
Carine Bonnon ◽  
Christophe Bel ◽  
Laurence Goutebroze ◽  
Bernard Maigret ◽  
Jean-Antoine Girault ◽  
...  
Keyword(s):  
Quality Control ◽  
Endoplasmic Reticulum ◽  
Cell Surface ◽  
Glial Cells ◽  
Molecular Mechanisms ◽  
Domain Swapping ◽  
Nodes Of Ranvier ◽  
Er Retention ◽  
Processing Signal ◽  
High Mannose

Formation of nodes of Ranvier requires contact of axons with myelinating glial cells, generating specialized axo-glial subdomains. Caspr/paranodin is required for the formation of septate-like junctions at paranodes, whereas the related caspr2 is essential for the organization of juxtaparanodes. The molecular mechanisms underlying the segregation of these related glycoproteins within distinct complexes are poorly understood. Exit of paranodin from the endoplasmic reticulum (ER) is mediated by its interaction with F3/contactin. Using domain swapping with caspr2, we mapped a motif with Pro-Gly-Tyr repeats (PGY) in the ectodomain of paranodin responsible for its ER retention. Deletion of PGY allows cell surface delivery of paranodin bypassing the calnexin-calreticulin quality control. Conversely, insertion of PGY in caspr2 or NrCAM blocks these proteins in the ER. PGY is a novel type of processing signal that compels chaperoning of paranodin by contactin. Contactin associated with paranodin is expressed at the cell surface with high-mannose N-glycans. Using mutant CHO lines altered in the processing of N-linked carbohydrates, we show that the high-mannose glycoform of contactin strongly binds neurofascin-155, its glial partner at paranodes. Thus, the unconventional processing of paranodin and contactin may determine the selective association of axo-glial complexes at paranodes.

Sign in / Sign up

Export Citation Format

Share Document