A Reverse Mutation E143K within the PrM Protein of Zika Virus Asian Lineage Natal RGN Strain Increases Infectivity and Cytopathicity

Chen-Sheng Lin; Wei-Jing Li; Chih-Yi Liao; Ju-Ying Kan; Szu-Hao Kung; Su-Hua Huang; Hsueh-Chou Lai; Cheng-Wen Lin

doi:10.3390/v14071572

A Reverse Mutation E143K within the PrM Protein of Zika Virus Asian Lineage Natal RGN Strain Increases Infectivity and Cytopathicity

Viruses. 2022 Jul 20;14(7):1572. doi: 10.3390/v14071572.

Authors

Chen-Sheng Lin¹, Wei-Jing Li², Chih-Yi Liao², Ju-Ying Kan³, Szu-Hao Kung⁴, Su-Hua Huang⁵, Hsueh-Chou Lai⁶, Cheng-Wen Lin^{2

3

5}

Affiliations

¹ Division of Gastroenterology, Kuang Tien General Hospital, No. 117, Shatian Rd, Shalu District, Taichung 433, Taiwan.
² Department of Medical Laboratory Science and Biotechnology, China Medical University, No. 100, Sec. 1, Jingmao Rd., Beitun Dist., Taichung 404, Taiwan.
³ The PhD Program of Biotechnology and Biomedical Industry, China Medical University, No. 100, Sec. 1, Jingmao Rd., Beitun Dist., Taichung 404, Taiwan.
⁴ Department of Biotechnology and Laboratory Science in Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan.
⁵ Department of Medical Laboratory Science and Biotechnology, Asia University, No. 500, Lioufeng Rd., Wufeng, Taichung 41354, Taiwan.
⁶ Division of Hepato-Gastroenterology, Department of Internal Medicine, China Medical University Hospital, No. 2, Yude Rd., North Dist., Taichung 404, Taiwan.

Abstract

Zika virus (ZIKV) is a positive-sense single-stranded RNA virus in the Flaviviridae, which is classified into two different lineages Asian and African. The outbreak of ZIKV Asian lineage isolates in 2015-2016 is associated with the increase in cases with prenatal microcephaly and Guillain-Barré syndrome, and has sparked attention throughout the world. Genome sequence alignment and the analysis of Asian and African lineage isolates indicate that amino acid changes, particular in positively charged amino acid substitutions in the pr region of prM protein might involve a phenotypic change that links with the global outbreak of ZIKV Asian-lineage. The study generated and characterized the virological properties of wild type and mutants of single-round infectious particles (SRIPs) and infectious clones (i.c.s) of ZIKV Asian-lineage Natal RGN strain, and then identified the function of amino acid substitutions at the positions 139 [Asn139→Ser139 (N139S)] and 143 [Glu143→Lys143 (E143K)] in ZIKV polyproteins (located within the pr region of prM protein) in the infectivity and cytopathogenicity. The E143K SRIP and i.c. of Natal RGN strain exhibited relatively higher levels of cytopathic effect, EGFP reporter, viral RNA and protein synthesis, and virus yield in three types of human cell lines, TE617, SF268 and HMC3, compared to wild type (WT), N139S SRIPs and i.c.s, which displayed more efficiency in replication kinetics. Additionally, E143K Natal RGN i.c. had greater activities of virus attachment and entry, yielded higher titers of intracellular and extracellular virions, and assembled the E proteins near to the plasma membrane in infected cells than the other i.c.s. The results indicate that the positively charged amino acid residue Lys143, a conserved residue in the pr region of prM of ZIKV African lineages, plays a crucial role in viral replication kinetics, including viral attachment, entry, assembly and egress. Thus, the negatively charged amino acid residue Glu143 within the pr region of prM leads to an alteration of the phenotypes, in particular, a lower replication efficiency of ZIKV Asian-lineage isolates with the attenuation of infectivity and cytopathicity.

Keywords: Asian lineage; Zika virus; amino acid substitution; cytopathicity; infectious clone (i.c.); infectivity; prM; single round infectious particle (SRIP).

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Amino Acids / genetics
Female
Humans
Mutation
Pregnancy
Viral Envelope Proteins* / genetics
Virus Replication
Zika Virus Infection*
Zika Virus* / pathogenicity

Substances

Amino Acids
Viral Envelope Proteins
prM protein, Flavivirus

Grants and funding

This study was financially supported by China Medical University, Taiwan (CMU110-S-03, CMU110-MF-61, CMU109-MF-57, and CMU109-S-09), and funded by grants from the Ministry of Science and Technology, Taiwan (MOST108-2320-B-039-039-MY3; MOST110-2923-B-039-001-MY3).