key: cord-0859522-tfc3vn1w
authors: Zandi, Milad; Behboudi, Emad; Soltani, Saber
title: Role of Glycoprotein Hemagglutinin-Esterase in COVID-19 Pathophysiology?
date: 2021-06-28
journal: Stem Cell Rev Rep
DOI: 10.1007/s12015-021-10210-1
sha: 4b5fdadfbf7baf549c2374c952b4b6d21fd3a35c
doc_id: 859522
cord_uid: tfc3vn1w

nan

One and a half year has passed since the outbreak of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) the causative agent of coronavirus disease 2019 (COVID-19) pandemic. Nowadays information on SARS-CoV-2 and its receptors are increasing. It's been showed that O-acetylated sialic acids (SAs) can interact with viral spike glycoprotein for the primary attachment of virus and its penetration into the host cells [1] . Most beta coronaviruses recognize 9-O-acetyl-SAs but it has changed to 4-O-acetyl-SA through the evolution of Coronaviruses [1] . Its viral ligand, the hemagglutinin esterase (HE) gene was transmitted to a beta coronavirus lineage A through horizontal gene adaption from a 9-O-acetyl-SA-specific HEF, as in influenza C [1, 2] . Adaption of HE occurs via cross-species transmission and HE evolution [1] . This fact demonstrates viral evolutionary compatibility to host glycans. Thus, studying emerging viruses like SARS-CoV-2 may result in better recognition of viral evolution process. For instance, as mentioned above, HE gene transfer is discovered in the beta coronaviruses, which choose 9-di-O-Ac-SAs. A more interesting example of such events happens in the murine CoVs, with attachment to two various subtypes of the canonical 9-O-Ac-SA (type I) and unique 4-O-Ac-SA (type II) [3] . But noticeably it must be mentioned that same as SARS-CoV-2, SARS-CoV genome has no HE gene [4] . Incorrectly a recent published article in the journal of stem cell reviews and reports states that SARS-CoV-2 has HE and hemagglutinin protein [5] , also the authors has illustrated viral hemagglutinin glycoprotein on viral envelope. This is in contrast to previous studies which experimentally showed that SARS-CoV-2 lacks HE gene and glycoprotein. According to data from different full genome sequencing studies using next generation sequencing (NGS) and phylogenic analysis of SARS-CoV-2 virus has no HE gene and consequently HE glycoprotein [4] . Therefore this virus lacks HE gene and cannot carry HE protein (Fig. 1) .

SARS-CoV-2 evolutionary adaptation toward host entry and recognition of receptor O-Acetyl sialylation in virus-host interaction

Structure and orientation of expressed bovine coronavirus hemagglutinin-esterase protein

Attachment of mouse hepatitis virus to O-acetylated sialic acid is mediated by hemagglutinin-esterase and not by the spike protein

Genomic characterization of the 2019 novel human-pathogenic coronavirus isolated from a patient with atypical pneumonia after visiting Wuhan

Does the global outbreak of COVID-19 or other viral diseases threaten the stem cell reservoir inside the body?