SARS-CoV-2 ORF7b: is a bat virus protein homologue a major cause of COVID-19 symptoms?

AbstractORF7b is an accessory protein of SARS-CoV-2, the virus behind the COVID-19 pandemic. Using cell-free synthesized ORF7b, we experimentally show that ORF7b assembles into stable multimers. The ORF7b sequence shows a transmembrane segment, which multimerizes through a leucine zipper. We hypothesize that ORF7b has the potential to interfere with important cellular processes that involve leucine-zipper formation, and present two particularly striking examples. First, leucine zippers are central in heart rhythm regulation through multimerization of phospholamban in cardiomyocytes. Second, epithelial cell-cell adhesion relies on E-cadherins, which dimerize using a transmembrane leucine zipper. Most common symptoms of SARS-CoV-2 infection, including heart arrythmias, odor loss, impaired oxygen uptake and intestinal problems, up to multiorgan failure, can be rationalized by a possible interference of ORF7b with the functions of these proteins. We ask whether this is pure coincidence, or whether our observations point to disruption by ORF7b of vital processes in COVID-19.

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Faculty Opinions recommendation of Spatio-temporal regulation of Rac1 localization and lamellipodia dynamics during epithelial cell-cell adhesion.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1009554.129409 ◽

2002 ◽

Author(s):

Yoshimi Takai

Keyword(s):

Cell Adhesion ◽

Epithelial Cell ◽

Temporal Regulation ◽

Spatio Temporal ◽

Cell Cell

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Faculty Opinions recommendation of Localized zones of Rho and Rac activities drive initiation and expansion of epithelial cell-cell adhesion.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1089749.544660 ◽

2007 ◽

Author(s):

Kathleen J Green

Keyword(s):

Cell Adhesion ◽

Epithelial Cell ◽

Cell Cell

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Stick around: Cell–Cell Adhesion Molecules during Neocortical Development

Cells ◽

10.3390/cells10010118 ◽

2021 ◽

Vol 10 (1) ◽

pp. 118

Author(s):

David de Agustín-Durán ◽

Isabel Mateos-White ◽

Jaime Fabra-Beser ◽

Cristina Gil-Sanz

Keyword(s):

Cell Adhesion ◽

Adhesion Molecules ◽

Cell Adhesion Molecules ◽

Neural Cells ◽

Surface Receptors ◽

Cellular Processes ◽

Neocortical Development ◽

Classical Cadherins ◽

Adhesive Interactions ◽

Cell Cell

The neocortex is an exquisitely organized structure achieved through complex cellular processes from the generation of neural cells to their integration into cortical circuits after complex migration processes. During this long journey, neural cells need to establish and release adhesive interactions through cell surface receptors known as cell adhesion molecules (CAMs). Several types of CAMs have been described regulating different aspects of neurodevelopment. Whereas some of them mediate interactions with the extracellular matrix, others allow contact with additional cells. In this review, we will focus on the role of two important families of cell–cell adhesion molecules (C-CAMs), classical cadherins and nectins, as well as in their effectors, in the control of fundamental processes related with corticogenesis, with special attention in the cooperative actions among the two families of C-CAMs.

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Solubility assessment of single-chain antibody fragment against epithelial cell adhesion molecule extracellular domain in four Escherichia coli strains

Journal of Genetic Engineering and Biotechnology ◽

10.1186/s43141-021-00126-1 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Fatemeh Sadat Javadian ◽

Majid Basafa ◽

Aidin Behravan ◽

Atieh Hashemi

Keyword(s):

Escherichia Coli ◽

Cell Adhesion ◽

Epithelial Cell ◽

Adhesion Molecule ◽

Cell Adhesion Molecule ◽

Extracellular Domain ◽

Epithelial Cell Adhesion Molecule ◽

Single Chain ◽

E Coli ◽

The Impact

Abstract Background Overexpression of the EpCAM (epithelial cell adhesion molecule) in malignancies makes it an attractive target for passive immunotherapy in a wide range of carcinomas. In comparison with full-length antibodies, due to the small size, the scFvs (single-chain variable fragments) are more suitable for recombinant expression in E. coli (Escherichia coli). However, the proteins expressed in large amounts in E. coli tend to form inclusion bodies that need to be refolded which may result in poor recovery of bioactive proteins. Various engineered strains were shown to be able to alleviate the insolubility problem. Here, we studied the impact of four E. coli strains on the soluble level of anti-EpEX-scFv (anti-EpCAM extracellular domain-scFv) protein. Results Although results showed that the amount of soluble anti-EpEX-scFv obtained in BL21TM (DE3) (114.22 ± 3.47 mg/L) was significantly higher to those produced in the same condition in E. coli RosettaTM (DE3) (71.39 ± 0.31 mg/L), and OrigamiTM T7 (58.99 ± 0.44 mg/L) strains, it was not significantly different from that produced by E. coli SHuffleTM T7 (108.87 ± 2.71 mg/L). Furthermore, the highest volumetric productivity of protein reached 318.29 ± 26.38 mg/L in BL21TM (DE3). Conclusions Although BL21TM (DE3) can be a suitable strain for high-level production of anti-EpEX-scFv protein, due to higher solubility yield (about 55%), E. coli SHuffleTM T7 seems to be better candidate for soluble production of scfv compared to BL21TM (DE3) (solubility yield of about 30%).

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Prognostic Value of Epithelial Cell Adhesion Molecules in T1‐2N0M0 Glottic Cancer

The Laryngoscope ◽

10.1002/lary.29348 ◽

2020 ◽

Author(s):

Naoya Murakami ◽

Taisuke Mori ◽

Ryunosuke Machida ◽

Takeshi Kodaira ◽

Yoshinori Ito ◽

...

Keyword(s):

Cell Adhesion ◽

Epithelial Cell ◽

Adhesion Molecules ◽

Cell Adhesion Molecules ◽

Prognostic Value ◽

Glottic Cancer

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The extracellular domain of epithelial cell adhesion molecule (EpCAM) enhances multipotency of mesenchymal stem cells through EGFR–LIN28–LET7 signaling

Journal of Biological Chemistry ◽

10.1074/jbc.ra119.007386 ◽

2019 ◽

Vol 294 (19) ◽

pp. 7769-7786 ◽

Cited By ~ 2

Author(s):

I.-I. Kuan ◽

Chi-Chiu Lee ◽

Chien-Hsu Chen ◽

Jean Lu ◽

Yuan-Sung Kuo ◽

...

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Cell Adhesion ◽

Epithelial Cell ◽

Adhesion Molecule ◽

Cell Adhesion Molecule ◽

Extracellular Domain ◽

Epithelial Cell Adhesion Molecule

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Redistribution and dysfunction of integrins in cultured renal epithelial cells exposed to oxidative stress

AJP Renal Physiology ◽

10.1152/ajprenal.1993.264.1.f149 ◽

1993 ◽

Vol 264 (1) ◽

pp. F149-F157 ◽

Cited By ~ 14

Author(s):

J. Gailit ◽

D. Colflesh ◽

I. Rabiner ◽

J. Simone ◽

M. S. Goligorsky

Keyword(s):

Oxidative Stress ◽

Cell Adhesion ◽

Epithelial Cell ◽

Epithelial Cells ◽

Cell Surface ◽

Apical Cell ◽

Flow Cytometric Analysis ◽

Adhesion Properties ◽

Renal Tubular Cells ◽

Renal Tubular

Tubular obstruction by detached renal tubular epithelial cells is a major cause of oliguria in acute renal failure. Viable renal tubular cells can be recovered from urine of patients with acute tubular necrosis, suggesting a possible defect in cell adhesion to the basement membrane. To study this process of epithelial cell desquamation in vitro, we investigated the effect of nonlethal oxidative stress on the integrin adhesion receptors of the primate kidney epithelial cell line BS-C-1. Morphological and functional studies of cell adhesion properties included the following: interference reflection microscopy, intravital confocal microscopy and immunocytochemistry, flow cytometric analysis of integrin receptor abundance, and cell-matrix attachment assay. High levels of the integrin subunits alpha 3, alpha v, and beta 1 were detected on the cell surface by fluorescence-activated cell sorting (FACS) analysis, as well as lower levels of alpha 1, alpha 2, alpha 4, alpha 5, alpha 6, and beta 3. Exposure of BS-C-1 cells to nonlethal oxidative stress resulted in the disruption of focal contacts, disappearance of talin from the basal cell surface, and in the redistribution of integrin alpha 3-subunits from predominantly basal location to the apical cell surface. As measured in a quantitative cell attachment assay, oxidative stress decreased BS-C-1 cell adhesion to type IV collagen, laminin, fibronectin, and vitronectin. Defective adhesion was not associated with a loss of alpha 3-, alpha 4-, or alpha v-integrin subunits from the cell surface.(ABSTRACT TRUNCATED AT 250 WORDS)

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