Research Interests

• Host restriction to viral infection and viral countermeasures
• Viral cell-to-cell transmission
• Innate immunity and sensing of viral infection
• Mechanisms of viral membrane fusion and entry
• Cell signaling, viral oncogenes, and human lung cancer
• Model viruses of study – HIV, Ebola virus, Influenza A virus, Zika virus, hepatitis C virus, and oncogenic sheep retroviruses

1.IFITM restriction of viral infection

The interferon (IFN) system is the first line of host defense against pathogen invasion, including viral infections. Shortly after IFN induction or viral infection, cells express hundreds of IFN-stimulated genes (ISGs) that modulate diverse biological processes, including the establishment of antiviral states. The IFN-induced transmembrane (IFITM) protein family belongs to a group of small ISGs (~15 kD) that block the early stages of viral replication. Specifically, IFITM proteins restrict entry of a wide range of viruses, including highly pathogenic influenza A virus (IAV), SARS coronarvirus, Ebolavirus (EBOV), and HIV.

Recent work from our lab and others showed that IFITM proteins inhibit cell-cell fusion by IAV HA, Semliki Forest virus (SFV) E1, and vesicular stomatitis virus (VSV) G proteins, which represent class I, II and III viral fusion proteins, respectively. Interestingly, we have found that some viruses are more sensitive than others to inhibition by particular types of IFITMs, suggesting that IFITM-mediated restriction of viral entry can be virus-strain specific and IFITM-species dependent (Li et al, PLoS Pathogens 2013). Indeed, we showed that IFITM2 and IFITM3, but not IFITM2, specifically interact with HIV-1 Env, thus inhibiting its processing and viral infectivity (Yu et al, Cell Reports, 2015). Currently, we are using a variety of biophysical, biochemical, forward genetics, as well as molecular approaches to dissect the distinct mechanisms of IFITM restriction of viral entry and cell-cell spread. The model viruses applied to this project include IAV, Ebola virus (EBOV), and HIV-1.

 

2.Viral entry, fusion and cell-to-cell transmission

Entry is the first step of viral replication and essential for viral pathogenesis. While the core mechanism of virus fusion and entry is known, it remains poorly understood how exactly viral fusion proteins are activated and how the entry process is controlled for most pathogenic animal viruses. The objective of this project is to better understand the mechanisms of membrane fusion and entry by EBOV and Zika virus. We are particularly focused on cellular and viral factors in the fusion triggering and entry process, including receptor binding, low pH, and additional cellular and viral determinants.

EBOV is a highly pathogenic filovirus that causes severe hemorrhagic fever in humans, with a fatality rate of up to 90%. Currently, there is no effective antiviral drug or FDA-approved vaccine against this deadly virus. Entry of EBOV into host cell is mediated by its sole glycoprotein, known as GP. It is believed that EBOV enters host cells through macropinocytosis, which is initiated by the binding of EBOV GP to attachment factors or cell surface receptors, such as DC-SIGN and TIM-1.Following the uptake of viral particles into late endosome and lysosome, GP is cleaved by cellular proteases, especially cathepsin L (CatL) and B (CatB), to a 19 kDa intermediate. The 19 kDa species then binds to human Niemann-Pick C1 (NPC1), the newly identified intracellular receptor of EBOV in endolysosomes, where virus-cell membrane fusion takes place. One recent interesting finding from our lab, in collaboration with Fredric Cohen’s lab at Rush University, is that low pH per se is not a trigger but that low pH-dependent cathepsin’s activity is critical for GP-mediated fusion (Markosan and Miao et al, PLoS Pathogens, 2016). Current experiments are focused on the exact mechanisms of triggering and fusion, with an ultimate goal to develop novel fusion inhibitors against EBOV. Similar efforts have been put on Zika virus, a flavivirus family member with distinct biological properties that are associated with microcephaly and neuronal damaging.

Because cell-to-cell transmission has been shown to be more efficient than the cell-free virus infection, we are also currently investigating viral and cellular factors that regulate EBOV and HIV-1 cell-to-cell transmission.

3.TIM, SERINC and HIV Nef

We recently discovered that TIM-family proteins potently inhibit release of HIV and other viruses in addition to promoting viral entry (Li et al. PNAS USA, 2014).  Specifically, we showed that expression of TIM-1 protein potently blocks HIV-1 

Gag release, resulting in accumulation of mature viral particles on the plasma membrane. Notably, TIM-1 mutants deficient for PS binding are incapable of blocking HIV-1 release. The inhibitory effect of TIM family proteins on viral release

 

can be extended to some other PS receptors, including AxL and RAGE, underscoring a general role of PS in HIV and other viral infections. However, it is currently unclear how viruses counteract TIM-mediated inhibition of viral release. The goal of this project is to understand how HIV-1 Nef protein might antagonize TIM-mediated restriction and how the newly discovered SERINC proteins, which are known to impair HIV infectivity but are antagonized by Nef, participate in this process.

 

4.Cell signaling, viral oncogene and human lung cancer

Retroviruses have played fundamental roles in our current understanding of the molecular and genetic basis of cancer. One focus of our lab is to better understand the novel mechanisms of cell transformation by some oncogenic viruses, including retroviruses. We have been focused on two oncogenic sheep retroviruses, Jaagsiekte sheep retrovirus (JSRV) and enzootic nasal tumor virus (ENTV), which cause contagious lung and nasal adenocarcinomas, respectively, in sheep and goats. Distinct from most acutely transforming retroviruses, the envelope (Env) proteins of JSRV and ENTV are active oncogenes that induce malignant transformation in vitro and in vivo. More interestingly, the sheep lung tumor induced by JSRV strongly resembles human bronchiolo-alveolar carcinoma (BAC), a subclass of human pulmonary adenocarcinomas that is less associated with cigarette smoking. Hence, JSRV could provide a useful model for understanding the etiology and carciogenesis of human lung cancer. Current projects include molecular characterizations of cell signaling events triggered by some viral oncogenes as well as discovery of new human viruses associated with human lung cancers.

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Memberships

Member, Infectious Disease Institute

Member, Center for Retrovirus Research

Member, Biomedical Sciences Graduate Program (BSGP)

Member, Molecular, Cellular, and Developmental Biology (MCDB) Program

Member, Medical Scientist Training Program (MSTP)

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Relevent Publications

1. Qu, P, J. P. Evans, C. Kurhade, C. Zeng，Y.-M. Zheng, K. Xu, P.-Y. Shi, X. Xie, and S.-L. Liu*. 2023. Determinants and Mechanisms of the Low Fusogenicity and Endosomal Entry of Omicron Subvariants. mBio. e03176-22.

2. Faraone, J., Qu, P, J. P. Evans, J. C. Carlin, M. Anghelina, P. Stevens, S. Fernandez, D. Jones, G. Lozanski, A. Panchal, L. J. Saif, E. M. Oltz1, R.J. Gumina, and S.-L. Liu*. 2023. Enhanced Neutralization Resistance of SARS-CoV-2 Omicron XBB, BR.2 and BA.2.3.20 Subvariants. Cell Reports Medicine. In Press.

3. Qu, P, J. P. Evans, J. Faraone, C. Carlin, M. Anghelina, P. Stevens, S. Fernandez, D. Jones, G. Lozanski, A. Panchal, L. J. Saif, E. M. Oltz1, K. Xu, R.J. Gumina, and S.-L. Liu*. 2022. Enhanced Neutralization Resistance of SARS-CoV-2 Omicron BQ.1, BQ.1.1, BA.4.6, BF.7 and BA.2.75.2 Subvariants. Cell Host & Microbe. November 21, 2022.

4. Qu, P, J. P. Evans, Y.-M. Zheng, C. Carlin, L. J. Saif, E. M. Oltz, K. Xu, R. J. Gumina, and S.-L. Liu. * 2022. Evasion of Neutralizing Antibody Responses of the SARS-CoV-2 Omicron BA.2.75 Variants. Cell Host & Microbe. S1931-3128(22)00471-1.

5. Azar, J., J. P. Evans, M. Sikorski, K. Chakravarthy, S. McKenney, I. Carmody, C. Zeng, R. Teodorescu, N. J. Song, J. Hamon, D. Bucci, M. Velegraki, C. Bolyard, K. P. Weller, S. Reisinger, S. A. Bhat, K. J. Maddocks, R. J. Gumina, A. N. Vlasova, E. M. Oltz, L. J. Saif, D. Chung, J. A. Woyach, P. G. Shields, S.-L. Liu*, Z. Li*, M. P. Rubinstein*. 2022. Suppression of de novo antibody responses against SARS-CoV2 and the Omicron variant after mRNA vaccination and booster in patients with B cell malignancies undergoing active treatment, but maintenance of pre-existing antibody levels against endemic viruses. JCI Insight. In Press.

6. Evans, J. P, C. Zeng, P. Qu, Y.-M. Zheng, C. Carlin, J. S. Bednash, G. Lozanski, R. Mallampalli, L. J. Saif, E. M. Oltz, P. Mohler, R. J. Gumina, and S.-L. Liu. * 2022. Neutralization of SARS-CoV-2 Deltacron and BA.3 Variants. New England Journal of Medicine. 386: 2340-2342.

7. Qu, P, J. Faraone, J. P. Evans, Y.-M. Zheng, C. Carlin, J. S. Bednash, G. Lozanski, R. Mallampalli, L. J. Saif, E. M. Oltz, P. Mohler, R. J. Gumina, and S.-L. Liu. * 2022. Neutralization of the SARS-CoV-2 Omicron BA.4/5 and BA.2.12.1 Subvariants. New England Journal of Medicine. 386: 2526-2528.

8. Qu, P, J. Faraone, J. P. Evans, Y.-M. Zheng, L. Yu, Q. Ma, C. Carlin, G. Lozanski, L. J. Saif, E. M. Oltz, R. J. Gumina, and S.-L. Liu. * 2022. Durability of Booster mRNA Vaccine against SARS-CoV-2 BA.4/5 and BA.2.12.1 Subvariants. New England Journal of Medicine. In Press. Sept 7, 2022.

9. Evans, J. P, C. Zeng, P. Qu, J. Faraone, Y.-M. Zheng, C. Carlin, J. S. Bednash, T. Zhou, G. Lozanski, R. Mallampalli, L. J. Saif, E. M. Oltz, P. Mohler, K. Xu, R. J. Gumina, and S.-L. Liu. * 2022. Neutralization of SARS-CoV-2 Omicron Sub-lineages BA.1, BA.1.1 and BA.2 and BA. Cell Host & Microbe. S1931-3128(22)00220-7.

10. Cui, Z, C. Zeng, F. Huang, F. Yuan, J. Yan, Y. Zhao, J. Huang, H. F. Staats, Jeffrey I. Everitt, G. D. Sempowski, H. Wang1, Y. Dong3*, S.-L. Liu*, and Q. Wang*. 2022. Cas13d knockdown of lung protease Ctsl prevents and treats SARS-CoV-2 infection. Nature Chemical Biology. July 25, 2022. doi: 10.1038/s41589-022-01094-4.

11. Tang, J., C. Zeng, T. M. Cox,C. Li, Y. M. Son, I. S. Cheon, Y. Wu, S. Behl, J. J. Taylor, R. Chakaraborty, A. J. Johnson, D. N Shiavo, J. P. Utz, J. S. Reisenauer, D. E. Midthun, J. J. Mullon, E. S. Edell, M. G. Alameh, L. Borish, M. H. Kaplan, D. Weissman, R. Kern, H. Hu, R.  Vassallo, S.-L. Liu*, and J. Sun*. 2022. Respiratory mucosal immunity against SARS-CoV-2 following mRNA vaccination. Science Immunology. July 19, 2022. doi: 10.1126/sciimmunol.add4853. 

12. Abdelhamid, A. G, J. N. Faraone, J. P. Evans, S.-L. Liu, and A. E. Yousef. 2022. SARS-CoV-2 and Emerging Foodborne Pathogens: Intriguing Commonalities and Obvious Differences. Pathogens. July 27, 2022. 

13. Evans, J. P., C. Zeng, C. Carlin, G. Lozanski, L. J. Saif, E. M. Oltz, R. J. Gumina, and S.-L. Liu*. 2022. Neutralizing Antibody Responses Elicited by SARS-CoV-2 mRNA Vaccination Wane Over Time and are Boosted by Breakthrough Infection. Sci Transl Med. 14 (637): eabn8057.

14. Zeng C, J.P., Evans, K. Chakravarthy, P. Qu, S. Reisinger, N.-J. Song N, M.P. Rubinstein M, P.G. Shields, Z. Li Z, and S.-L. Liu*. 2022. COVID-19 mRNA booster vaccines elicit strong protection against SARS-CoV-2 Omicron variant in patients with cancer. Cancer Cell. Dec 30: S1535-6108(21)00688-7.

15. Zeng C, J. P., Evans JP, T, King, Y.-M. Zheng, E. M., Oltz, S. P. J, Whelan, L. J. Saif, M. E., Peeples ME, and S.-L. Liu*. 2021.SARS-CoV-2 Spreads through Cell-to-Cell Transmission. Proc. Natl. Acad. Sci. USA. 119(1): e2111400119.

16. Zeng, C, J. P. Evans, J. N. Faraone, P. Qu, Y.-M. Zheng, L. J. Saif, E. M. Otlz, G. Lozanski, R. J. Gumina and S.-L. Liu*. 2021. Neutralization of SARS-CoV-2 Variants of Concern Harboring Q677H. mBio. 12(5): e0251021.

17. Zeng, C, A. A. Waheed, T. Li, J. Yu, Y.-M. Zheng, J. Yount, H. Wen, E.O. Freed, and S.-L. Liu*. 2021. SERINC Proteins Potentiate Antiviral Type I IFN Induction and Proinflammatory Signaling Pathways. Science Signaling 14: eabc7611, Sept 14.

18. Zeng, C, J. P. Evans, S. Reisinger, J. Woyach, C. Liscynesky, Z. E. Boghdadly, M. P. Rubinstein, K. Chakravarthy, L. Saif, E. M. Oltz, R. J. Gumina, *Peter G. Shields, Z. Li*, and S.-L. Liu*. 2021. Impaired Neutralizing Antibody Response to COVID-19 mRNA Vaccine in Cancer Patients. Cell & Bioscience.11(1):197.

19. Gyang, TC*, J. P. Evans, J. Miller, K. Alcorn, J. Peng, E. Bell, C. Zeng, R. J. Gumina, B. Segal, and S.-L. Liu*. 2021. Efficacy of SARS-CoV-2 Vaccination in Patients with Multiple Sclerosis. Multiple Sclerosis Journal—Experimental, Translational and Clinical. 8(1): 20552173221087357.

20. Lu, M, P. Dravid, Y. Zhang, S. Trivedi, A. Li, O. Harder, K.C. Mahesh, S. Chaiwatpongsakorn, A. Zani, A. Kenney, C. Zeng, C. Cai, C. Ye, X. Liang, M. Shimamura, S.-L. Liu, P. N Boyaka, J. Qiu, L. Martinez-Sobrido, J. Yount, M. Peeples, Kapoor, S. Niewiesk, and J. Li. 2021. A safe and highly efficacious measles virus-based vaccine expressing SARS-CoV-2 stabilized prefusion spike. Proc. Natl. Acad. Sci. USA. Mar 23;118(12): e2026153118.

21. Evans, J. P, and S.-L. Liu*. 2021. Role of host factors in SARS-CoV-2 Entry. J. Biol. Chem. 297(1):100847.

22. Kim, E, Z. Attia, R. M. Woodfint, C.Zeng, S. Kim, H. E. Steiner, R. K. Shukla, N. P. M. Liyanage, J. Li, G. J. Renukaradhya, A. A. Satoskar, A. O. Amer, S.-L. Liu, E. Cormet-Boyaka, and P. N. Boyaka. 2021. Inhibition of elastase enhances the adjuvanticity of alum and promotes anti–SARS-CoV-2 systemic and mucosal immunity. Proc. Natl. Acad. Sci. USA. 118 (34) e2102435118.

23. Lu M, Y. Zhang, P. Dravid, A. Li, C. Zeng, K C Mahesh, S. Trivedi, H. Sharma, S. Chaiwatpongsakorn, A. Zani, A. Kenney, C. Cai, C. Ye, X. Liang, J. Qiu, L. Martinez-Sobrido, J. S. Yount, P. N. Boyaka, S.-L. Liu, M. E. Peeples, A. Kapoor, J. Li J. 2021. A methyltransferase-defective VSV-based SARS-CoV-2 vaccine candidate provides complete protection against SARS-CoV-2 infection in hamsters. J. Virol. doi: 10.1128/JVI.00592-21

24. Zeng, C, J. P. Evans, R. Pearson, P. Qu, Y.-M. Zheng, R. T. Robinson, L. Hall-Stoodley, J. Yount, S. Pannu, R. K. Mallampalli, L. Saif, E. Oltz, G. Lozanski, and S.-L. Liu*. 2020. Neutralizing antibody against SARS-CoV-2 spike in COVID-19 patients, health care workers and convalescent plasma donors. JCI Insight. 5(22): e143213.

25. Wu, Y, W. Ho, Y. Huang, D.-Y. Jin, S. Li, S.-L. Liu, X. Liu, J, Qiu, Y. Sang, Q. Wang, K.-Y. Yuen, and Z.-M. Zheng. 2020. SARS-CoV-2 is an appropriate name for the new coronavirus. The Lancet 395 (10228): 949-950.

26. Liu, S.-L.*, L. Saif, S. R. Weiss, and L. Su*. 2020. No Credible Evidence Supporting Claims of the Laboratory Engineering of SARS-CoV-2. Emerg. Microbes & Infect. 9(1):505-507. doi: 10.1080/22221751.2020.1733440.

27. M. Chemudupati, A. Smith, R. Fillinger, A. Kenney, L. Zhang, A. Zani, S.-L. Liu, M. Z. Anderson, A. Sharma, and J. Yount. 2020. Butyrate Reprograms Expression of Specific Interferon- Stimulated Genes. J. Virol. 94 (16). E00326-20.

28. Zeng, C, A. A. Waheed, T. Li, J. Yu, Y.-M. Zheng, J. Yount, H. Wen, E.O. Freed, and S.-L. Liu*. 2020. SERINC Proteins Potentiate Antiviral Type I IFN Induction and Proinflammatory Signaling Pathways. Proceedings. 2020, 50, 51; doi:10.3390.

29. Liu, S.-L*. New Virus in China Requires International Control Effort. 2020. Nature 577(7791): 472.

30. Liu, S.-L.*, and L. Saif. 2020. Emerging Viruses without Borders: The Wuhan Coronavirus. Viruses. 12(2). pii: E130. doi: 10.3390/v12020130.

31. Li, A. Xue, Z. Attia, J. Yu, M. Lu, C. Shan, X. Liang, T. Z. Gao, P.-Y. Shi, M. E Peeples, P. N. Boyaka, S.-L. Liu, J. Li. 2020. Vesicular Stomatitis Virus and DNA Vaccines Expressing Zika Virus Nonstructural Protein 1 Induce Substantial but Not Sterilizing Protection against Zika Virus Infection. J. Virol. 94 (17): e00048-20.

32. Li, M.#, A. A. Waheed#,J. Yu#, C. Zeng, H.-Y. Chen,Y.-M. Zheng, A. Feizpour, B. Reinhard, S. Gummuluru,S. Lin, E. O. Freed, and S.-L. Liu*. 2019. TIM-mediated Inhibition of HIV-1 Release Is Antagonized by Nef but Potentiated by SERINC Proteins. Proc. Natl. Acad. Sci. USA. 116 (12): 5705-5714. (#Co-first author)

33. Yu, J, C. Liang, and S.-L. Liu*. 2019. CD4-dependent Modulation of HIV-1 Entry by LY6E. J. Virol. 93 (7): pii: e01866-18.

34. Yu, J and S.-L. Liu*. 2019. Emerging Role of LY6E in Virus-Host Interactions. Viruses. 11 (11). piiE: 1020. 

35. Zani, A, L. Zhang, T. M. McMichael, A. Kenney, M. Chemudupati, J. J. Kwiek, S.-L. Liu, and J. S. Yount. 2019. IFITMs Inhibit Cell Fusion Mediated by Trophoblast Syncytins. J. Biol. Chem. Nov 17. pii: jbc.AC119.010611.

36. Yu, J, V. Murthy, and S.-L. Liu*. 2019. Relating GPI-anchored Ly6/uPAR and CD59 Proteins to Viral Infection. Viruses. 11 (11). pii E:1060. 

37. Evans, J and S-L. Liu.* 2019. Multifaceted Roles of TIM-family Proteins in Virus-host Interactions. Trends Microbiol. pii: S0966-842X (19)30259-8.

38. Beitari, S, Y. Wang, S.-L. Liu and C. Liang. 2019. HIV-1 Envelope Glycoprotein at the Interface of Host Restriction and Virus Evasion. Viruses, 11(4), 311.

39. Lu S, Z Han, M.-C. Hung, J Xu, Y,Xu, P Zheng, Z.-M. Zheng, L. Zou, Z Li, L Zheng, Y Kang, Y Yang, L He, X.-C. Liao, H Yu, Z Yue, S.-L. Liu* and H Zheng. 2019. Racial Profiling Harms Science. Science 363(6433):1290-1292.

40. Wang, T, Q. Du, Y. Niu, X. Zhang, M. He, Z. Wang, X. Wu, X. Yang, X. Zhao, S.-L. Liu, D. Tong, and Y. Huang. 2019. Cellular p32 Is a Critical Regulator of the Porcine Circovirus Type 2 Nuclear Egress. J. Virol. 93(23). pii: e00979-19.

41. Kodigepalli, K.M, M. Li, S. Bonifati, S.-L. Liu, and L. Wu. 2018. SAMHD1 inhibits epithelial cell transformation in vitro and affects leukemia development in xenograft mice. Cell Cycle. Nov 26. doi: 10.1080/15384101.2018.1550955.

42. Yu, J, and S.-L. Liu*. 2018. The Inhibition of HIV-1 Entry Imposed by Interferon Inducible Transmembrane Proteins Is Independent of Co-Receptor Usage. Viruses 10 (8). Pii: E413.

43. Li, A., J. Yu, M. Lu, Y. Ma, Z. Attia, C. Shan, J. He, X. Liang, M. Xue, R. Jennings, P.-Y. Shi, M. Peeples, S.-L. Liu, P. Boyaka, J. Li. 2018. A Zika virus vaccine expressing premembrane-envelope-NS1 polyprotein. Nat. Commun. 9 (1): 3067.

44. Yu, J., C. Liang and S.-L. Liu*. 2017. Interferon-inducible LY6E Protein Promotes HIV Infection. J. Biol. Chem. 292(11):4674-4685.

45. Wang, Y., Q. Pan, Z. Wang, J. Yu, S.-L. Liu and C. Liang. 2017. The V3-loop of HIV-1 Env Determines Viral Susceptibility to IFITM3 Impairment of Viral Infectivity. J. Virol. 91(7). pii: e02441-16.

46. Miller, A.D., M. de Las Heras, J. Yu, F. Zhang, S.-L. Liu, A. E. Vaughan, T. L. Vaughan, R. Rosadio, S. Rocca, G. Palmieri, J. J.Goedert, J. Fujimoto, I. I. Wistuba. 2017. Evidence against a role for Jaagsiekte sheep retrovirus in human lung cancer. Retrovirology. 14(1):3.

47. Markosyan, R.M.#, C. Miao#, Y.-M. Zheng, G.B. Melikian, S.-L. Liu* and F.S. Cohen*. 2016. Induction of Cell-Cell Fusion by Ebola Virus Glycoprotein: Low pH Is not a Trigger. PLoS Pathogens. 12(1): e1005373. (# Co-first author)

48. Miao, C, M. Li, Y.-M. Zheng, F. S. Cohen and S.-L. Liu*. 2015. Cell-cell Contact Promotes Ebola Virus GP-mediated Infection. Virology. 488:202-215.

49. Yu, J, M. Li, J. Wilkins, S. Ding, T. H. Swartz, A. M. Esposito, Y.-M. Zheng, E. O. Freed, C. Liang, B. K. Chen, and S.-L. Liu*.2015. IFITM Proteins Antagonize HIV-1 Envelope to Restrict Cell-to-cell Infection. Cell Reports 13: 145-156.

50. Li, K, R. Jia, M. Li, Y.-M. Zheng, C. Miao, Y. Yao, H. Ji, Y. Geng, W. Qiao, Lorraine M. Albritton, Chen Liang, and S.-L. Liu*. 2015. A Sorting Signal Intrinsically Suppresses IFITM1 Restriction of Viral Entry. J. Biol. Chem. 290 (7): 4248-4259. 

51. Li, M, S. Ablan, C. Miao, Y.-M. Zheng, M. S. Fuller, P. D. Rennert, W. Maury, M. Johnson, E. O. Freed, and S.-L. Liu*. 2014 TIM Family Proteins Inhibit HIV-1 Release. Proc Natl Acad Sci USA. 111(35): E3699-707.

52. Ding, S, Q. Pan, S.-L. Liu*, and C. Liang*. 2014. HIV-1 mutates to escape IFITM1 restriction. Virology 454-455: 11-24

53. Li K#, R. M. Markosyan#, Y.-M. Zheng#, O. Golfetto, B. Bungart, M. Li, S. Ding, Y. He, C. Liang, J. C. Lee, E. Gratton, F. S. Cohen, and S.-L. Liu*. 2013. IFITM Proteins Restrict Viral Membrane Hemifusion. PLoS Pathogens. 9 (1): e1003124. (# equal contribution)

54. Côté M.#, Y.-M. Zheng#, and S.-L. Liu*. 2012. Membrane fusion and cell entry of XMRV is pH-independent and modulated by the envelope glycoprotein’s cytoplasmic tail. PLoS ONE. 7(3):e33734. (#equal contribution)

55. Côté M#, Y.-M. Zheng#, Kun Li, S-H Xiang, Lorraine M. Albritton and S.-L. Liu*. 2012. Critical Role of a Leucine-Valine Change in the Distinct Low pH Requirements for Membrane Fusion between Two Related Retrovirus Envelopes. J. Bio. Chem. 287(10):7640-51. (#equal contribution) 

56. Côté M., Y.-M. Zheng and S.-L. Liu*. 2011. Single Residues in the Surface Subunits of Oncogenic Sheep Retrovirus Envelopes Distinguish Their Receptor-mediated Triggering for Fusion at Low pH and Infection. Virology 421(2): 173-183.

57. Lu J, Q. Pan Q, L. Rong, S.-L. Liu, and Liang C. 2011. The IFITM proteins inhibit HIV-1 infection. J. Virol. 85: 2126-2137.

58. Côté M., Y.-M. Zheng and S.-L. Liu*. 2009.  Receptor Binding and Low pH Coactivate Oncogenic Retrovirus Envelope-mediated Fusion. J. Virol. 83: 1144-11455.

59. Côté M., T. Kucharski, Y.-M. Zheng and S.-L. Liu*. 2008. Enzootic Nasal Tumor Virus Requires a Very Acidic pH for Fusion Activation and Infection. J. Virol. 82: 9023-9034.

60. Côté M., Y.-M. Zheng, L. M. Albritton, and S.-L. Liu*. 2008. The Fusogenicity of Jaagsiekte Sheep Retrovirus Envelope Glycoprotein is Dependent on Low pH and Is Enhanced by the Cytoplasmic Tail Truncations.  J. Virol. 82: 2543-2554.

61. Bertrand P., M. Côté, Y.-M. Zheng, L. M. Albritton, and S.-L. Liu*. 2008. Jaagsiekte Sheep Retrovirus Utilizes a pH-dependent Endocytosis Pathway for Entry. J. Virol. 82:2555-2559.

62. Liu S.-L.* and A. D. Miller. 2007. Oncogenic Transformation by the JaagsiekteSheep Retrovirus Envelope Protein. Oncogene. 26:789-01. 

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