Endoplasmic Reticulum–Plasma Membrane Contact Sites: Regulators, Mechanisms, and Physiological Functions

Li, Chenlu; Qian, Tiantian; He, Ruyue; Wan, Chunrong; Liu, Yinghui; Yu, Haijia

doi:10.3389/fcell.2021.627700

Cited by 39 publications

(37 citation statements)

References 219 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…PM cholesterol therefore serves as first regulator in a viral life cycle, which is either supplied by ER-PM contact sites or ERC-PM contact sites. While various adaptors for ER-PM shuttling have been identified ( Naito et al, 2019 ; Li et al, 2021 ), ERC-PM contacts present as rather enigmatic although evidently being similarly important ( Hölttä-Vuori et al, 2002 ; Möbius et al, 2003 ; Garbarino et al, 2012 ; Iaea et al, 2017 ). Further elucidation of the latter and how it is modulated by viruses thus presents as important aspect of focus.…”

Section: Endosomal Cholesterol Trafficking As Shared Feature In Viral Infectionsmentioning

confidence: 99%

Endosomal Cholesterol in Viral Infections – A Common Denominator?

Glitscher

Hildt

2021

Front. Physiol.

View full text Add to dashboard Cite

Cholesterol has gained tremendous attention as an essential lipid in the life cycle of virtually all viruses. These seem to have developed manifold strategies to modulate the cholesterol metabolism to the side of lipid uptake and de novo synthesis. In turn, affecting the cholesterol homeostasis has emerged as novel broad-spectrum antiviral strategy. On the other hand, the innate immune system is similarly regulated by the lipid and stimulated by its derivatives. This certainly requires attention in the design of antiviral strategies aiming to decrease cellular cholesterol, as evidence accumulates that withdrawal of cholesterol hampers innate immunity. Secondly, there are exceptions to the rule of the abovementioned virus-induced metabolic shift toward cholesterol anabolism. It therefore is of interest to dissect underlying regulatory mechanisms, which we aimed for in this minireview. We further collected evidence for intracellular cholesterol concentrations being less important in viral life cycles as compared to the spatial distribution of the lipid. Various routes of cholesterol trafficking were found to be hijacked in viral infections with respect to organelle-endosome contact sites mediating cholesterol shuttling. Thus, re-distribution of cellular cholesterol in the context of viral infections requires more attention in ongoing research. As a final aim, a pan-antiviral treatment could be found just within the transport and re-adjustment of local cholesterol concentrations. Thus, we aimed to emphasize the importance of the regulatory roles the endosomal system fulfils herein and hope to stimulate research in this field.

show abstract

Section: Endosomal Cholesterol Trafficking As Shared Feature In Viral Infectionsmentioning

confidence: 99%

Endosomal Cholesterol in Viral Infections – A Common Denominator?

Glitscher

Hildt

2021

Front. Physiol.

View full text Add to dashboard Cite

show abstract

“…The ER can also form Ca 2+ conducive membrane interphases with the PM (76) and this interaction is critical for the process of store operated Ca 2+ entry (SOCE) into the ER and cytosol from the extracellular space with the tethering of the membranes mediated by the proteins ORAI and Stromal interaction molecules (STIMs) (76). SOCE plays an important role in the nerve terminals where α-syn is present in high concentrations (77).…”

Section: Ryrmentioning

confidence: 99%

Endoplasmic Reticulum-Based Calcium Dysfunctions in Synucleinopathies

2021

View full text Add to dashboard Cite

Neuronal calcium dyshomeostasis has been associated to Parkinson's disease (PD) development based on epidemiological studies on users of calcium channel antagonists and clinical trials are currently conducted exploring the hypothesis of increased calcium influx into neuronal cytosol as basic premise. We reported in 2018 an opposite hypothesis based on the demonstration that α-synuclein aggregates stimulate the endoplasmic reticulum (ER) calcium pump SERCA and demonstrated in cell models the existence of an α-synuclein-aggregate dependent neuronal state wherein cytosolic calcium is decreased due to an increased pumping of calcium into the ER. Inhibiting the SERCA pump protected both neurons and an α-synuclein transgenic C. elegans model. This models two cellular states that could contribute to development of PD. First the prolonged state with reduced cytosolic calcium that could deregulate multiple signaling pathways. Second the disease ER state with increased calcium concentration. We will discuss our hypothesis in the light of recent papers. First, a mechanistic study describing how variation in the Inositol-1,4,5-triphosphate (IP3) kinase B (ITPKB) may explain GWAS studies identifying the ITPKB gene as a protective factor toward PD. Here it was demonstrated that how increased ITPKB activity reduces influx of ER calcium to mitochondria via contact between IP3-receptors and the mitochondrial calcium uniporter complex in ER-mitochondria contact, known as mitochondria-associated membranes (MAMs). Secondly, it was demonstrated that astrocytes derived from PD patients contain α-synuclein accumulations. A recent study has demonstrated how human astrocytes derived from a few PD patients carrying the LRRK2-2019S mutation express more α-synuclein than control astrocytes, release more calcium from ER upon ryanodine receptor (RyR) stimulation, show changes in ER calcium channels and exhibit a decreased maximal and spare respiration indicating altered mitochondrial function in PD astrocytes. Here, we summarize the previous findings focusing the effect of α-synuclein to SERCA, RyR, IP3R, MCU subunits and other MAM-related channels. We also consider how the SOCE-related events could contribute to the development of PD.

show abstract

“…This symmetric process, on either side of the cell wall at the graft interface, would require the precise spatial-temporal coordination of processes between the scion and the rootstock. This coordination could be mediated by signals produced during the cell wall remodeling (For reviews: Anderson and Kieber, 2020; Duman et al, 2020) and/or by local ER-plasma membrane interactions (For review: Li et al, 2021a). The genesis of a large central cavity, by for example the formation of hemi-PD running in parallel to the cell wall, could increase the chance of alignment of both hemi-PD on either side of the graft interface.…”

Section: Discussionmentioning

confidence: 99%

A CLEM approach to access to the ultrastructure at the graft interface in Arabidopsis thaliana

Chambaud

Cookson

Ollat

et al. 2021

Preprint

View full text Add to dashboard Cite

Despite recent progress in our understanding of the graft union formation, we still know little about the cellular events underlying the grafting process. This is partially due to the difficulty of reliably targeting the graft interface in electron microscopy to study its ultrastructure and three-dimensional architecture. To overcome this technological bottleneck, we developed a correlative light electron microscopy approach (CLEM) to study the graft interface with high ultrastructural resolution. Grafting hypocotyls of Arabidopsis thaliana lines expressing YFP or mRFP in the endoplasmic reticulum allowed the efficient targeting of the grafting interface for under light and electron microscopy. To explore the potential of our method to study sub-cellular events at the graft interface, we focused on the formation of secondary plasmodesmata (PD) between the grafted partners. We showed that 4 classes of PD were formed at the interface and that PD introgression into the call wall was initiated equally by both partners. Moreover, the success of PD formation appeared not systematic with a third of PD not spanning the cell wall entirely. Characterizing the ultrastructural characteristics of these failed PD gives us insights into the process of secondary PD biogenesis. We showed that the thinning of the cell wall and the endoplasmic reticulum-plasma membrane tethering seem to be required for the establishment of symplastic connections between the scion and the rootstock. The resolution reached in this work shows that our CLEM method offer a new scale to the study for biological processes requiring the combination of light and electron microscopy.

show abstract

Endoplasmic Reticulum–Plasma Membrane Contact Sites: Regulators, Mechanisms, and Physiological Functions

Cited by 39 publications

References 219 publications

Endosomal Cholesterol in Viral Infections – A Common Denominator?

Endosomal Cholesterol in Viral Infections – A Common Denominator?

Endoplasmic Reticulum-Based Calcium Dysfunctions in Synucleinopathies

A CLEM approach to access to the ultrastructure at the graft interface in Arabidopsis thaliana

Contact Info

Product

Resources

About