Basic Science

Discovery of a 382-nt deletion during the early evolution of SARS-CoV-2

In this study the authors report a novel deletion of the SARS-CoV-2 genome which spans 382 nucleotides within the viral open reading frame 8 (ORF8). Given that ORF8 variants of SARS-CoV play a role in replicative fitness and host adaptation following interspecies transmission, the authors suggest that the identified deletion could possibly lead to an attenuated phenotype of SARS-CoV-2.

SARS-Cov-2 Can Infect T Cells Via Its Spike Protein

Lymphocytopenia is commonly observed in SARS-CoV-2 positive individuals and may be related to the mortality rate for COVID-19. In this study, the authors demonstrate the ability of SARS-CoV-2 to infect T lymphocytes. Furthermore, the authors confirm that the viral spike protein (protein S) -mediated membrane fusion process is responsible for the entry of SARS-CoV-2 into T cells, and propose that other membrane receptors may mediated SARS-CoV-2 entry site for SARS-CoV-2, in addition to the already confirmed hACE2 receptor.

Coronavirus endoribonuclease targets viral polyuridine sequences to evade activating host sensors

To avoid being recognized by the immune system, coronaviruses (CoVs) express factors that interfere with host sensors. A coronavirus endoribonuclease (EndoU) cleaves a viral PolyUridine Negative-sense RNA (PUN RNA) that would be otherwise recognised by the host sensor MDA5, thus delaying the immune interferon (IFN) response. EndoU is highly conserved in all CoVs, hence it might be used as target for therapeutic approaches.

MINI REVIEW – Analysis of SARS-CoV-2/Human Interactome

To develop therapeutic strategies against SARS-CoV-2, the etiological agent of the novel respiratory tract disease CoViD-19, it is crucial to understand the strategies through which the virus acts. The use of bioinformatics approaches led to the identification of host dependency factors that may mediate viral infection and pathogenesis and can provide key information regarding the molecular targets useful for the development of broad-spectrum antiviral therapies against SARS-CoV-2.

MINIREVIEW: The journey of SARS-CoV-2: from bats to humans, across pangolins

The ongoing outbreak of CoViD-19 is associated with a novel coronavirus, SARS-CoV-2. Although bats (Rhinolophus affinis) are likely natural reservoirs for SARS-CoV-2, an unknown intermediate host might have facilitated transfer to humans. Results of these studies suggest that Malayan pangolins (Manis javanica), like other wild animals, could be considered as possible sources of contagion for novel Coronaviruses and it poses an important concern whether animal species should be removed from wet markets to prevent further zoonotic transmissions.