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Related Experiment Video

Updated: Jul 9, 2025

Engineering Antiviral Agents via Surface Plasmon Resonance

Engineering Antiviral Agents via Surface Plasmon Resonance

Published on: June 14, 2022

Calreticulin Regulates SARS-CoV-2 Spike Protein Turnover and Modulates SARS-CoV-2 Infectivity.

Nader Rahimi¹, Mitchell R White^2,3, Razie Amraei¹

¹Department of Pathology, School of Medicine, Boston University, Boston, MA 02118, USA.

|December 9, 2023

Summary

Calreticulin (CALR) interacts with the SARS-CoV-2 spike protein, influencing its proteostasis and viral infection. This discovery offers new insights into COVID-19 cardiovascular complications.

Keywords:

COVID-19 S-RBD SARS-CoV-2 calreticulin endothelial cells intracellular calcium homeostasis spike protein

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High-throughput Confocal Imaging of Quantum Dot-Conjugated SARS-CoV-2 Spike Trimers to Track Binding and Endocytosis in HEK293T Cells

High-throughput Confocal Imaging of Quantum Dot-Conjugated SARS-CoV-2 Spike Trimers to Track Binding and Endocytosis in HEK293T Cells

Published on: April 21, 2022

Area of Science:

Molecular Biology
Virology
Cell Biology

Background:

Cardiovascular complications are significant in COVID-19.
Mechanisms of SARS-CoV-2 endothelial cell infection are not fully understood.

Purpose of the Study:

To investigate the interaction between SARS-CoV-2 spike protein and endothelial cells.
To identify host factors involved in SARS-CoV-2 infection and proteostasis.

Main Methods:

Biochemical analysis to identify S-RBD interacting proteins.
Cell treatments with proteasomal and lysosomal inhibitors.
shRNA-mediated knockdown of calreticulin (CALR).

Main Results:

Calreticulin (CALR) identified as an S-RBD interacting protein via its proline-rich domain.
CALR modulates spike protein proteostasis, particularly in lysosome-dependent degradation.
CALR knockdown increased SARS-CoV-2 infection and impaired endothelial cell calcium homeostasis.

Conclusions:

CALR plays a crucial role in the ER-lysosome-dependent proteolysis of the SARS-CoV-2 spike protein.
CALR's function in spike protein degradation and calcium homeostasis is vital for endothelial cell integrity.
Findings suggest a link between CALR, SARS-CoV-2 infection, and COVID-19-associated cardiovascular complications.