Deregulation of the Host Cell Cycle Induced by SARS‐CoV‐2 Nucleocapsid Protein

Introduction: The novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARSCoV2) is the causative agent responsible for the COVID-19 pandemic and has resulted in devastating impacts on global public health. The nucleocapsid (N) protein of other coronaviruses, such as SARS-CoV-1, have been previously implicated in the deregulation of the host cell cycle through interactions with cell cycle checkpoint proteins, Cyclin-Dependent Kinases (CDKs) or cyclins. In this study, we highlight the role of SARS-CoV-2 N-protein in modulating CDK expression, thereby, deregulating the host cell cycle. Methods: A549 cells were transfected with pCMV plasmids, harbouring the SARS-CoV-2 N-protein. Protein extracts of control and Nprotein transfected cells were electrophoresed on SDS-PAGE, transferred onto a nitrocellulose membrane and incubated with CDK2 and CDK4 antibodies. The blots were visualized and protein quantification was performed using ImageJ analysis. Results: Transfection of SARS-CoV-2 N resulted in differential expression of CDK2 and CDK4, which are key regulators that drive cell cycle progression through G0 or G1 phase into S phase. Notably, preliminary findings also demonstrate that N protein results in decreased CDK2 and CDK4 expression. Conclusion: The differential expression of CDKs caused by SARS-CoV-2 N-protein suggests its role in inducing cell cycle arrest at the S phase to facilitate SARS-CoV-2 replication. The results from this research may aid in future characterisation of the mechanisms for SARS-CoV-2-mediated cell cycle arrest, and contribute towards the development of novel antiviral strategies and therapies.

Current Perspective of Plant-Based Diets on Communicable Diseases Caused by Viruses: A Mini Review.

Communicable diseases are illnesses caused by pathogenic biological agents, including viruses, bacteria, fungi, parasites, and protozoa. Such diseases spread among people through contact with contaminated surfaces, bodily fluids, or blood products, or through the air, insect bites, or consuming contaminated food and beverages. Although some communicable diseases can be treated or prevented by taking medication and vaccines, there has been an increase in awareness of adopting a healthy diet to aid in the prevention and reversal of these diseases. One popular diet is a plant-based diet. Plant-based diets generally consist of vegetables, grains, nuts, seeds, legumes, and fruits, without any animal-source foods or artificial ingredients. Over the years, this diet has continuously increased in popularity. Reasons for following a plant-based diet are varied but include health benefits, such as improving immunity, and reducing the risk of heart disease, diabetes, and some cancers. Scientific evidence even shows that just an increased vegetable intake can decrease the occurrence of chronic diseases caused by viruses, such as hepatitis viruses, and reduce the risk of severe coronavirus disease 2019. Therefore, this mini review discusses the effectiveness of adopting a plant-based diet in ameliorating diseases caused by selected viruses and its limitations.