GILT restricts the cellular entry mediated by the envelope glycoproteins of SARS-CoV, Ebola virus and Lassa fever virus

Zheng

et al. 2020

Preprint

Self Cite

25C3A is a sub-clone of human hepatoblastoma HepG2 cell line with the strong contact inhibition 26 of growth. We fortuitously found that C3A was more susceptible to human coronavirus HCoV-27 OC43 infection than HepG2, which was attributed to the increased efficiency of virus entry into 28 C3A cells. In an effort to search for the host cellular protein(s) mediating the differential 29 susceptibility of the two cell lines to HCoV-OC43 infection, we found that ADAP2, GILT and 30 LY6E, three cellular proteins with known activity of interfering virus entry, expressed at 31 significantly higher levels in HepG2 cells. Functional analyses revealed that ectopic expression 32 of LY6E, but not GILT or ADAP2, in HEK 293 cells inhibited the entry of HCoV-OC43. While 33 overexpression of LY6E in C3A and A549 cells efficiently inhibited the infection of HCoV-34 OC43, knockdown of LY6E expression in HepG2 significantly increased its susceptibility to 35HCoV-OC43 infection. Moreover, we found that LY6E also efficiently restricted the entry 36 mediated by the envelope spike proteins of other human coronaviruses, including the currently 37 pandemic SARS-CoV-2. Interestingly, overexpression of serine protease TMPRSS2 or 38 amphotericin treatment significantly neutralized the IFITM3 restriction of human coronavirus 39 entry, but did not compromise the effect of LY6E on the entry of human coronaviruses. The 40 work reported herein thus demonstrates that LY6E is a critical antiviral immune effector that 41 controls CoV infection and pathogenesis via a distinct mechanism.

Section: Resultssupporting

confidence: 93%

Section: Introductionmentioning

confidence: 68%

Section: Introductionmentioning

confidence: 99%

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LY6E Restricts the Entry of Human Coronaviruses, including the currently pandemic SARS-CoV-2

Zheng

et al. 2020

Preprint

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“…Interferons (IFNs) are the primary antiviral cytokines that mediate innate and adaptive immune control of virus infection by inducing hundreds of genes, many of which encode antiviral effectors (36) (42,43). We also demonstrated recently that GILT suppresses the entry of SARS-CoV, but not other human CoVs (38). As reported herein, in our efforts to identify host on October 30, 2020 by guest http://jvi.asm.org/ Downloaded from factor(s) determining the differential susceptibility of two closely related human hepatoma cell lines to HCoV-OC43 infection, we found that LY6E potently suppresses the infectious entry of all the human CoVs, including the currently pandemic SARS-COV-2.…”

Section: Downloaded Frommentioning

confidence: 99%

LY6E Restricts Entry of Human Coronaviruses, Including Currently Pandemic SARS-CoV-2

Zheng

et al. 2020

J Virol

Self Cite

C3A is a sub-clone of human hepatoblastoma HepG2 cell line with strong contact inhibition of growth. We fortuitously found that C3A was more susceptible to human coronavirus HCoV-OC43 infection than HepG2, which was attributed to the increased efficiency of virus entry into C3A cells. In an effort to search for the host cellular protein(s) mediating the differential susceptibility of the two cell lines to HCoV-OC43 infection, we found that ArfGAP with dual pleckstrin homology (PH) domains 2 (ADAP2), gamma-interferon-inducible lysosome/endosome-localized thiolreductase (GILT) and lymphocyte antigen 6 family member E (LY6E), the three cellular proteins with identified function of interfering virus entry, expressed at significantly higher levels in HepG2 cells. Functional analyses revealed that ectopic expression of LY6E, but not GILT or ADAP2, in HEK 293 cells inhibited the entry of HCoV-O43. While overexpression of LY6E in C3A and A549 cells efficiently inhibited the infection of HCoV-OC43, knockdown of LY6E expression in HepG2 significantly increased its susceptibility to HCoV-OC43 infection. Moreover, we found that LY6E also efficiently restricted the entry mediated by the envelope spike proteins of other human coronaviruses, including the currently pandemic SARS-CoV-2. Interestingly, overexpression of serine protease TMPRSS2 or amphotericin treatment significantly neutralized the IFITM3 restriction of human coronavirus entry, but did not compromise the effect of LY6E on the entry of human coronaviruses. The work reported herein thus demonstrates that LY6E is a critical antiviral immune effector that controls CoV infection and pathogenesis via a mechanism distinct from other factors that modulate CoV entry. IMPORTANCE Virus entry into host cells is one of the key determinants of host range and cell tropism and is subjected to the control by host innate and adaptive immune responses. In the last decade, several interferon inducible cellular proteins, including IFITMs, GILT, ADAP2, 25CH and LY6E, had been identified to modulate the infectious entry of a variety of viruses. Particularly, LY6E was recently identified as host factors to facilitate the entry of several human pathogenic viruses, including human immunodeficiency virus, influenza A virus and yellow fever virus. Identification of LY6E as a potent restriction factor of coronaviruses expands the biological function of LY6E and sheds new light on the immunopathogenesis of human coronavirus infection.

“…This system has been widely used in studies of coronavirus entry. To improve the expression level of S protein and the yield of pseudotyped virus, a codon-optimized S gene based on the sequence of isolate Wuhan-Hu-1 (2) was synthesized and used for production of pseudotyped virus as previously described for other human coronaviruses (HCoVs), including SARS-CoV, MERS-CoV, NL63, 229E, and OC43 (31,32). The pseudotyped virus was then used to infect 293T cells transfected with either empty vector, or a plasmid expressing APN (receptor for HCoV-229E), DDP4 (receptor for MERS-CoV), ACE1 or hACE2.…”

Section: Human Ace2 Serves As a Functional Receptor For Sars-cov-2mentioning

confidence: 99%

Broad and differential animal ACE2 receptor usage by SARS-CoV-2

Szabla

et al. 2020

Preprint

Self Cite

24The COVID-19 pandemic has caused an unprecedented global public health and 25 economy crisis. The origin and emergence of its causal agent, SARS-CoV-2, in the 26 human population remains mysterious, although bat and pangolin were proposed to be 27 the natural reservoirs. Strikingly, comparing to the SARS-CoV-2-like CoVs identified in 28 bats and pangolins, SARS-CoV-2 harbors a polybasic furin cleavage site in its spike (S) 29 glycoprotein. SARS-CoV-2 uses human ACE2 as its receptor to infect cells. Receptor 30 recognition by the S protein is the major determinant of host range, tissue tropism, and 31 pathogenesis of coronaviruses. In an effort to search for the potential intermediate or 32 amplifying animal hosts of SARS-CoV-2, we examined receptor activity of ACE2 from 33 14 mammal species and found that ACE2 from multiple species can support the 34 infectious entry of lentiviral particles pseudotyped with the wild-type or furin cleavage 35 site deficient S protein of SARS-CoV-2. ACE2 of human/rhesus monkey and rat/mouse 36 exhibited the highest and lowest receptor activity, respectively. Among the remaining 37 species, ACE2 from rabbit and pangolin strongly bound to the S1 subunit of 38 SARS-CoV-2 S protein and efficiently supported the pseudotyped virus infection. These 39 findings have important implications for understanding potential natural reservoirs, 40 zoonotic transmission, human-to-animal transmission, and use of animal models. 41 42 43 44